DEVELOPMENT OF CNS By Dr Samina Anjum NERVOUS SYSTEM The central nervous system (CNS): - Brain and spinal cord The peripheral nervous system (PNS): - Neurons.
Download ReportTranscript DEVELOPMENT OF CNS By Dr Samina Anjum NERVOUS SYSTEM The central nervous system (CNS): - Brain and spinal cord The peripheral nervous system (PNS): - Neurons.
Slide 1
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 2
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 3
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 4
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 5
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 6
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 7
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 8
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 9
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 10
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 11
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 12
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 13
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 14
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 15
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 16
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 17
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 18
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 19
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 20
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 21
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 22
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 23
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 24
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 25
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 2
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 3
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 4
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 5
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 6
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 7
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 8
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 9
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 10
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 11
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 12
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 13
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 14
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 15
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 16
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 17
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 18
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 19
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 20
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 21
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 22
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 23
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 24
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU
Slide 25
DEVELOPMENT OF CNS
By Dr Samina Anjum
NERVOUS SYSTEM
The central nervous system (CNS):
- Brain and spinal cord
The peripheral nervous system (PNS):
- Neurons outside the CNS
- Cranial and spinal nerves that connect the brain and
spinal cord with peripheral structures
The autonomic nervous system (ANS):
- Has parts in both the CNS and PNS.
Neurulation
CNS appears at the beginning of 3rd week of development.
Closure of Neural Tube
Day 25 Rostral
neuropore closes
Day 28 Caudal
neuropore closes
Ectoderm to Neuroectoderm: 20 days
to 30 days
Rhombencephalic
isthmus
Pontine flexure
BRAIN FLEXURES
4th week
Rhombencephalic isthmus
Cephalic/Midbrain flexure
Cervical flexure
Pontine flexure
Flexures cause variation in outline
of T.S of brain at various levels &
in position of grey & white
substance
Pontine flexure
Development of Spinal Cord
Neuroepithelial, Mental and
Marginal layers
(White matter
Of S.C)
Neuroblasts (Gray matter of S.C)
Neuroepithelium
With Junctional
complexes at the
lumen
Basal, Alar, Roof & Floor plates
Histological Differentiation
Nerve cells, Glial cells & Neural crest cells
Vascular
Transient dendrite
Marginal layer
Lie b/w Blood vessels and neurons
SPINAL NERVES
Neural Crest Cells
NEURAL CREST CELLS
Myelination
Spinal cord begins in 4th month---1st year
Tracts in N.S myelinate when they start functioning
Neurilemmal sheath
PNS
CNS
Positional Changes in Spinal Cord
Subarachnoid space
3rd
month
End of 5th month
New born
Adult
Spina bifida occulta
Spina bifida cystica
Spina bifida
Meningomyelocele
Myeloschisis
Acrania, Cerebral regression &
Anencephaly
PITUITARY GLAND-ECTODERMAL
Rathke’s pouch
(Ectodermal out pocketing of stomodeum)
embryo is 3 weeks
End of 2nd month
Looses its connection with oral cavity
THANK YOU