Transcript Tissues - Anatomy and Physiology

Bellwork
• Define tissue. (Hint – look at your
crossword or your notes from chapter 1!)
• Tissue: A group of cells that work together
for the same function.
Tissues
4 Main Tissue Types
• 1 – Epithelial
• 2 – Connective
• 3 – Muscle
• 4 – Nervous
Tissues differ from each other in
size, shape, amount, kind of
material, and function.
1 – Epithelial Tissue
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Covers body and parts.
Packed tightly together
No blood vessels
Basement membrane anchors to tissue
underneath
• Regenerate easily
1 – Epithelial Tissue
Shape
A) Squamous – Flat and scale like
B) Cuboidal – Cube shaped
C) Columnar – Higher than wide
Arrangement
A) Simple – Single layer of same shaped cells
B) Stratified – Many layers of same shaped cells
C) Transitional – Several layers of different shaped cells
1 – Epithelial Tissue
Simple Squamous
• Single layer, flat, scale-like
• Function – Absorption
• Ex. Oxygen into blood from
lungs (capillaries and alveoli)
Stratified Squamous
• Several layers of closely
packed cells
• Function – Protection from
microorganisms
• Ex. Skin and mucous
membranes
1 – Epithelial Tissue
Stratified Transitional
• Found in areas needed to stretch
• Usually ten or more layers (protection) when not
stretched
• When stretching occurs, epithelial sheet
expands to form a few layers
• Ex. Urinary bladder
Simple Columnar
• Contain “goblet cells” which produce mucous.
• Specialize in absorption.
• Ex. Inner surfaces of stomach, intestines, and parts of
respiratory and reproductive tracts.
1 – Epithelial Tissue
Pseudo-stratified
• Appears to be two layered but
actually is not (pseudo – false)
• Absorption and secretion
• Contain cilia
• Ex. Trachea and windpipe
Glandular
• Act alone or in groups (glands).
• Exocrine glands – Release products into
ducts. (Ex. Liver)
• Endocrine glands – Release hormones
into bloodstream. (Ex. Thyroid)
Interesting Fact
• Up to 90% of human cancers originate in
epithelial cells.
Exit Ticket
• Describe as many general characteristics
about epithelial tissue as you can. (Hint –
We had 5 in our notes)
Connective, Muscle and Nervous
Tissue
2 – Connective Tissue
• Most abundant type of tissue
• Vary in blood supply
• Extracellular matrix – non-living material
surrounding living cells
• Protein fibers and ground substance (mostly
water)
2 – Connective Tissue
A) Areolar
• Thin delicate membranes
• “Glue” that anchors internal organs.
• Ex. Subcutaneous layer below skin
B) Adipose
• Space between cells so they may swell,
nucleus pushed to one side
• Specialized to store lipids, insulation
C) Reticular
• Thin network of fibers
• Provides support in organs which hold free
blood cells (lymph nodes, spleen)
2 – Connective Tissue
D) Bone (osseous tissue)
• Matrix is hard and calcified.
• Store Calcium and Phosphorus
• Provide protection and support.
E) Dense
• Make up tendons and ligaments
2 – Connective Tissue
F) Blood
• Liquid matrix
• Function – Transportation and
Protection
• Ex. Red and White blood cells
G) Cartilage
• 3 types:
• Hyaline – fetal skeleton
• Elastic – ears
• Fibrocartilage – intervertebral discs
3 – Muscle Tissue
• 3 Types
A) Skeletal (Striated)
• Voluntary -can be
willfully controlled.
• Many nuclei
• Individual cells appear
threadlike.
• Attached to bones create movement.
3 – Muscle Tissue
B) Cardiac
• Only in heart
• Involuntary
• Striations and
intercalated disks.
• Allows the heart to
beat
3 – Muscle Tissue
C) Smooth (Visceral)
• Form walls of hollow
organs (blood vessels,
intestines)
• Involuntary
• Non- striated
4 – Nervous Tissue
• Neurons and
support cells
• Send impulses to
other areas of the
body
Nerve Tissue
• Neurons contain 1
axon (carry
impulses away
from cell body)
and 1 or more
dendrites (carry
impulses to cell
body)
Tissue Discussion
• Three patients in an ICU are
examined by the doctor. One pt
has brain damage from a stroke,
another had a heart attack that
severely damaged his heart
muscle, and the third has a
severely damaged liver (a
gland) from a crushing injury in
a car accident. All 3 pts have
stabilized and will survive, but
only one will have full
functional recover through
regeneration. Which one and
why?
Tissue Discussion
• Cancer-causing agents
(carcinogens) usually
act on dividing cells.
Which of the four
tissues would
carcinogens most
influence? Why?
Tissue Discussion
• Joints such as the
shoulder, elbow, and
knee contain
considerable amounts
of cartilage and dense
regular connective
tissue. How does this
explain that joint
injuries are often slow
to heal?
Tissue Repair
• Regeneration
• Replacement of
destroyed tissue by the
same kind of cells
• Fibrosis
• Repair by dense
fibrous connective
tissue (scar)