Transcript SNC2 Biology Review
Slide 1
SNC2 Biology Review
Slide 2
What is an Organism?
• An organism is a living thing. It is easy to
recognise a living thing, but not so easy to
define it. Animals and plants are
organisms, obviously. Organisms are
a biotic, or living, part of the environment.
Rocks and sunshine are parts of the nonliving environment abiotic.
Slide 3
Know the difference between
•
Quark: Simply energy. Can’t be seen under any microscope.
Atom: Made from quarks. Has protons, neutrons. These make molecules.
Molecule: These are made from Atoms. Examples of molecules are: Hydrogen,
Oxygen.
Organelle: Made of molecules and are the small organs in each cell. Examples in
animal cells are: Nucleus, Ribosome, Lysosome.
Cell: Made up of organelles. Cells are the building blocks of life.
Tissue: Made from similar cells. Each organ has specific types of cells that make that
particular organ and its parts.
Organ: Similar types of tissue (example muscle tissue, heart tissue) makeup an
organ.
Organ System: Organs that work together to help an organism execute a specific
function (breathing, thinking, etc) are part of an organ system.
Organism: An organism is the person/thing.
Slide 4
Nucleus
• The nucleus is the large
control centre of a cell,
directing all of the cell's
activities.
• Chromosomes that
contain your DNA are
stored in this organelle.
• The nucleus is separated
from the rest of the cell by
the nuclear membrane.
Slide 5
Ribosome
• Found on the
endoplasmic
reticulum or free in
the cytoplasm.
• Proteins are made
in this organelle.
Slide 6
Mitochondria
• The mitochondria is
sometimes referred to as
the powerhouse of the
cell.
• Mitochondria are largely
responsible for providing
the cell with energy from
glucose (sugar) through a
process called cellular
respiration.
Slide 7
Golgi Bodies
• Golgi bodies collect and
process materials to be
removed from the cell.
• They also make and
secrete mucus.
• Cells that secrete a lot of
mucus, such as cells
lining the intestine, have
many Golgi bodies.
Slide 8
Endoplasmic Reticulum
• The endoplasmic
reticulum is a threedimensional network of
branching tubes and
pockets.
• It extends throughout the
cytoplasm from the
nuclear membrane.
• These fluid-filled tubes
transport materials, such
as proteins, through the
cell.
Slide 9
Chloroplast
• Looks like: green stacks
of membranes that
contain chlorophyll
• Job: perform
photosynthesis (convert
sunlight into energy)
Slide 10
Vacuole
• Looks like: sac-like
organ. HUGE in plant
cells
• Job: stores water, food,
and waste
Slide 11
Vesicles
• A vesicle can be
seen as a bubble of
liquid within a cell.
• It is a small
membrane-enclosed
sack that can store
or transport
material.
Slide 12
Cell Membrane
• Looks like: layered
membrane surrounding the
cell but inside of the cell wall
• Job: “the regulator”-controls what
comes in and out of the cell,
protects, and supports the cell
Slide 13
Cell Wall
• Looks like: thick layer outside the plasma membrane
• Job: structure and support
Slide 14
Nuclear Membrane
Slide 15
What is the Cell Cycle?
As eukaryotic cells grow and divide, they pass
through a cell cycle that consists of 3 stages:
• Interphase
• Mitosis (cell division)
• Cytokinesis (cell division)
Slide 16
What happens?
Slide 17
STAGE of CELL CYCLE
Slide 18
Stage 1: Interphase
• Interphase is the longest stage of the cell cycle
• The cell performs its normal functions and, in
preparation for cell division, duplicates its genetic
material (DNA)
Slide 19
Slide 20
Stage 2: Cell Division - Mitosis
Consists of 4 phases:
Prophase
Metaphase
Anaphase
Telophase
Slide 21
Mitosis Phase 1:Prophase
• DNA compacts into
visible form as
chromosomes
• Each chromosome
contains two strands
called sister chromatids.
• Sister chromatids are
held together by a
centromere
• The nuclear membrane
breaks down
Slide 22
Mitosis Phase 2: Metaphase
• Chromosomes line up
in the middle of the
cell.
Slide 23
Mitosis Phase 3: Anaphase
• The centromere splits
and sister chromatids
separate.
• They are now called
daughter
chromosomes.
• They move to
opposite ends of the
cell, pulled by spindle
fibres
Slide 24
Mitosis Phase 4: Telophase
• Final phase of
mitosis.
• Chromosomes stretch
out and are no longer
visible.
• A new nuclear
membrane forms
around each group of
daughter
chromosomes.
Slide 25
Stage 3: Cell Division - Cytokinesis
• Final stage of cell division
and cell cycle
• The cytoplasm divides
and two genetically
identical cells are formed.
In a plant cell, a plate
develops into a new cell
wall
• In an animal cell, the cell
membrane is pinched off
in the centre
Slide 26
Plant vs Animal (Cytokinesis)
• In a plant cell, a plate develops into a new
cell wall
• In an animal cell, the cell membrane is
pinched off in the centre forming two
membranes,
Slide 27
Plant vs. Animal Cells
There are three main differences between
plant and animal cells:
1. Plant cells have a
cell wall, Animal
Cells do not
Slide 28
Plant vs. Animal Cells
2. Plant cells have
chloroplasts and
Animal Cells do not
Slide 29
Plant vs. Animal Cells
3. Plant cells have
larger vacuoles
(storage spaces)
Slide 30
Plant vs. Animal Cells
Plant Cells
1.Chloroplasts
2.Cell wall
3.Large
vacuole
Animal Cells
1.No Chloroplasts
2.No Cell wall
3.Small Vacuole
Slide 31
Plant vs. Animal Cells
Different Shapes (Plants are rectangles, and Animals are round)
Slide 32
Stages of Pregnancy and
Development
Fertilization
Embryonic development - Cleavage
Fetal - Differentiation
Growth – Development
Childbirth
Slide 33
Fertilization
The egg is viable for 12 to 24 hours after ovulation
Sperm are viable for 12 to 48 hours after ejaculation
Sperm cells must make their way to the uterine tube for
fertilization to be possible
Slide 34
ZYGOTE
1. The sperm and egg join to form a zygote: the first
cell of a new individual.
2. Zygote results of the fusion of DNA from sperm and
egg
2. Fertilization occurs in the Fallopian Tubes
3. The zygote begins rapid mitotic cell division
4. Beginning of human development
Slide 35
Differentiation
EMBRYO
0.5 cms
20 days after fertilization
•Embryo begins to form organs during
the third week.
•Cannot tell if it is human or other
vertebrate. Tall visible.
Slide 36
Differentiation
EMBRYO
1 months
0.6 cms
• Ears, nose and eyes not visible
• Small arm and leg buds, backbone seen
• Heart beats.
Slide 37
Differentiation
FETUS •
2 months
•
3 cms
During the second month most of the major
organ systems form, limb buds develop.
Limbs distinct with fingers and toes bones
begin to form, eyes far apart.
• The embryo becomes a fetus by the seventh
week.
Slide 38
Differentiation
All organ systems are
formed by the end of the
eighth week
Activities of the fetus are
growth and organ
specialization
A stage of tremendous
growth and change in
appearance
Fetus at nine weeks
3 cm
Slide 39
Differentiation
FETUS
2 months
3 cms
•Beginning the eighth week, the sexually
neutral fetus activates gene pathways for
sex determination, forming testes in XY
fetuses and ovaries in XX fetuses.
•External genitalia develop.
Slide 40
Developmental Aspects of the
Reproductive System
Gender is determined at fertilization
Males have XY sex chromosomes
Females have XX sex chromosomes
Gonads do not begin to form until the
eighth week
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide
Slide 41
Four Basic Kinds of Tissues
• Epithelial Tissue
• Connective Tissue
• Muscle Tissue
• Nervous Tissue
Slide 42
Epithelial Tissue
• Epithelial Tissue Locations:
– Covers the body
– Lines the cavities, tubes, ducts and blood
vessels inside the body
– Covers the organs inside body cavities
• Epithelial Tissue Functions:
– Protection from physical & chemical injury,
– Protection against microbial invasion,
• Examples: Skin, small intestine
Slide 43
Connective Tissue
• Connective Tissue:
– Most abundant & widely distributed tissue
• Connective Tissue Functions:
– Connects, binds and supports structures,
• Tendons, ligaments, etc.
– Protects & cushions organs and tissues,
– Insulates (fat) and
– Transports substances (blood).
Example: Bone and Blood.
Slide 44
Muscle Tissue
• Muscle Tissue:
– Associated with the bones of the skeleton, the heart and in the
walls of the hollow organs of the body.
• Muscle Tissue Functions:
– Movement
– Locomotion
– Maintains posture
– Produces heat
– Facial expressions
– Pumps blood
– Peristalsis
Example: arm, stomach, heart
Slide 45
Nervous Tissue
• Nervous Tissue:
– Main component of the nervous system,
ie., brain, spinal cord & nerves.
• Nervous Tissue Functions:
– Regulates & controls body functions
– Generates & transmits nerve impulses
– Supports, insulates and protects impulse generating neurons.
There are three types of neurons,
sensory neurons
motor neurons.
connector neurons
Slide 46
Cell Specialization
• All cells carry the same DNA
information but they do not
perform the same functions and
may not look the same.
• All cells start their lives as identical
cells called stem cells.
• The process of a cell becoming a
particular type of cell is called cell
differentiation.
Slide 47
• Groups of cells that function together and are specialized
for common tasks are called tissues.
• In simple terms, they are groups of cells that work
together to do the same job
Slide 48
Human Organ Systems
Slide 49
Levels of Organization
Remember, the human body is organized in several levels,
from the simplest to the most complex. . .
Cells – the basic unit of life
Tissues – clusters of cells performing a similar function
Organs – made of tissues that perform one specific
function
Organ Systems – groups of organs that perform a
specific purpose in the human body
***The purpose of the 11 organ systems is for the human body
to maintain homeostasis.
Slide 50
Homeostasis
• Homeostasis is: The ability or tendency
of an organism or cell to maintain internal
equilibrium by adjusting its physiological
processes.
Slide 51
The 11 Human Body Systems
The 11 human body systems are as follows:
-- nervous system
-- integumentary system
-- respiratory system
-- digestive system
-- excretory system
-- skeletal system
-- muscular system
-- circulatory system
-- endocrine system
-- reproductive system
-- lymphatic (immune) system
Slide 52
The Digestive System
Purpose: to convert food particles into simpler
micromolecules that can be absorbed into the
bloodstream and used by the body
Major Organs and their Functions:
Mouth – to chew and grind up food
-- saliva also begins the chemical breakdown
Esophagus – pipe connecting mouth to stomach
Stomach – secretes an extraordinarily strong acid (pH = 2) that
leads to breakdown of food
-- once the food is broken down in the stomach and
mixed with digestive juices, it is called chyme
Slide 53
Pancreas – produces the hormone insulin that regulates
blood
sugar levels
-- also help neutralize stomach acid
Liver – produces bile, which breaks down fats in foods
Gallbladder – pouch-like organ that stores bile for future use
Small Intestine – after digestion is complete, the chyme
enters the small intestine where it is absorbed into the
bloodstream
-- the chyme is propelled along by folded surfaces
called villi, on the intestine
Large Intestine – removes water from the chyme and gets the
waste ready for excretion
Slide 54
The Digestive System
Slide 55
The Respiratory System
Purpose: to provide the body with a fresh supply of oxygen
for cellular respiration and remove the waste product carbon
dioxide
Major Organs and Their Functions
Nose – internal entry and exit point for air
Pharynx – serves as a passage way for both air and food at
the back of the throat
Larynx – your “voicebox”, as air passes over your vocal
chords, you speak
Trachea – the “windpipe”, or what connects your pharynx to
your lungs
-- a piece of skin, called the epiglottis, covers the
trachea when you swallow, preventing food from
entering
Slide 56
Bronchi – the two large passageways that lead from the
trachea to your lungs (one for each lung)
-- the bronchi are further subdivided into bronchioles
-- eventually, the further subdivisions lead to tiny air
sacs called alveoli
-- alveoli are in clusters, like grapes
-- capillaries surrounding each alveolus is where
the exchange of gases with the blood occurs
The diaphragm is the muscle that causes you to breath
-- hiccups are involuntary contractions of the
diaphragm
Slide 57
Image of the Respiratory System
Slide 58
The Circulatory System
Purpose: to deliver oxygenated blood to the various cells and
organ systems in your body so they can undergo cellular
respiration
Major Organs and Their Functions
Heart – the major muscle of the circulatory system
-- pumps blood through its four chambers (two
ventricles and two atria)
-- pumps deoxygenated blood into the lungs, where it
gets oxygenated, returned to the heart, and then
pumped out through the aorta to the rest of the body
-- valve regulate the flow of blood between the
chambers
Slide 59
Arteries – carry blood away from the heart and to the major
organs of the body
Veins – carry blood back to the heart away from the major
organs of the body
Capillaries – small blood vessels where gas exchange occurs
Blood – the cells that flow through the circulatory system
-- red blood cells contain hemoglobin, an iron-rich
protein that carries oxygen
-- white blood cells function in the immune system
-- platelets help in blood clotting
Spleen – helps to filter out toxins in the blood
Slide 60
Image of the Circulatory System
Slide 61
THE HUMAN HEART
The human heart
consists of 4
chambers
there are two types of
chambers: the atrium
and the ventricle
there are two of each
type in the heart
the heart weighs a
mere 300 grams
Slide 62
HEART VALVES
The human heart contains valves which
prevent blood from flowing back into the
heart chambers after it has contracted
atrioventricular valves are found
between the atrium and ventricle of
each side of the heart
semilunar valves are found in the
arteries leaving the heart to prevent
blood from flowing back into the
ventricles
Slide 63
HEART AT WORK
Each minute of the
day the heart pumps
5 litres of blood
each time the heart
beats it sends
deoxygenated blood
to the lungs and
oxygenated blood to
the body
Slide 64
THE HEART TO THE LUNGS
Blood enters the right
atrium of the heart via
two large veins: the
superior vena cava
and the inferior vena
cava
blood exits the right
ventricle of the heart
through the
pulmonary artery to
the lungs
Slide 65
Direction of Blood
Slide 66
THE HEART TO THE BODY
(Circulatory and Respiratory)
Blood reenters the left
artrium of the heart
via the pulmonary
vein
blood on the left side
of the heart is
oxygenated and is
pumped into the body
by the left ventricle
through the aorta
Slide 67
What is cancer?
• Caner is defined as the continuous
uncontrolled growth of cells.
• A tumor is a any abnormal proliferation of
cells.
• Benign tumors stays confined to its original
location
• Malignant tumors are capable of invading
surrounding tissue or invading the entire body
• Tumors are classified as to their cell type
• Tumors can arise from any cell type in the
body
Slide 68
What is Melanoma?
1. A type of skin cancer
2. Some risk factors
include:
1. Sun exposure depleting ozone layer
2. Presence of many or
unusual moles
3. Skin types
4. Genetics
predisposition
Slide 69
skin
benign
malignant
Slide 70
Slide 71
Diagnosis and
Medical Imaging
Technology
SNC2D
Slide 72
Diagnosis
• The interdependence of our organ systems can
sometimes make it difficult to pinpoint the source
of a medical problem.
• Doctors are trained to look for symptoms that
are characteristic of specific problems.
Slide 73
Diagnosis
• The interdependence of our organ systems can
sometimes make it difficult to pinpoint the source
of a medical problem.
• Doctors are trained to look for symptoms that
are characteristic of specific problems (e.g.
swollen lymph nodes are a symptom of
infection).
Slide 74
Tools of the Trade
To collect information about what’s going on
inside the body, doctors may use devices
like the stethoscope (to listen to the heart
and lungs)
Slide 75
Tools of the Trade
To collect information about what’s going on
inside the body, doctors may use devices
like the stethoscope (to listen to the heart
and lungs) and a sphygmomanometer (to
measure blood pressure).
Slide 76
Tests of the Trade
Doctors may also order tests of material
collected from the body (such as blood
and urine) which may be analyzed by a
separate lab.
E.g. Blood may be tested to determine the levels
of red blood cells, white blood cells, sugar, and
hormones – the chemicals that carry messages
through the body to regulate the functioning of
organs.
Slide 77
Medical Imaging Technologies
Diagnostic imaging tests can provide
doctors with even more information: an
actual visual picture of the structure and
functioning of organs.
However, these technologies are often
expensive, and the effectiveness of each
technology is limited by its properties.
Slide 78
Endoscopy
An endoscope is a thin, flexible tube that
has a bright light and a video camera that
can be used to image the digestive tract,
as in a colonoscopy.
Slide 79
Endoscopy
An endoscope is a thin, flexible tube that
has a bright light and a video camera that
can be used to image the digestive tract,
as in a colonoscopy.
Slide 80
Thermography
In thermograms, infrared light cameras are
used to diagnose problems with
circulation.
Normal
Raynaud’s syndrome
Slide 81
X-Rays
X-rays are high-energy electromagnetic
radiation that can easily penetrate soft
tissues but cannot easily penetrate bone.
Slide 82
X-Rays
X-rays are used to check for cancers (e.g.
mammograms), to diagnose problems in
the circulatory and respiratory systems,
and to check for broken bones.
They are quick, painless, and non-invasive
but exposure to x-rays can damage cells
and increases cancer risk.
Slide 83
Body Scanners
Note that this is also true for the body
scanners that are used at airports,
especially the new “naked body scanners.”
Slide 84
Body Scanners
Since the radiation emitted by these body
scanners is absorbed at the level of the
skin, it is your skin cancer risk that is most
increased – and the scans cannot find
anything concealed in any body cavity.
Slide 85
Body Scanners
Since the radiation emitted by these body
scanners is absorbed at the level of the
skin, it is your skin cancer risk that is most
increased – and the scans cannot find
anything concealed in any body cavity.
Also, like most x-rays, they do not show
contrast that may be used to identify soft
materials (like plastics and chemical
explosives).
Slide 86
Body Scanners
Since the radiation emitted by these body
scanners is absorbed at the level of the
skin, it is your skin cancer risk that is most
increased – and the scans cannot find
anything concealed in any body cavity.
Also, like most x-rays, they do not show
contrast that may be used to identify soft
materials (like plastics and chemical
explosives).
In other words, they’re completely
Slide 87
Computed Tomography
Computed tomography
(CT) scans, also called
computer-assisted
tomography (CAT)
scans, use x-rays to
produce images at
different angles
through the body so
that a 3D image can be
constructed.
Slide 88
Computed Tomography
CT scans may be used to diagnose cancers,
skeletal abnormalities and vascular
diseases (affecting blood vessels).
But since CT scans use x-rays, they also
increase your cancer risk.
Slide 89
Fluoroscopy
Fluoroscopy is a technique in which a
continuous beam of x-rays is used to
produce moving images.
It is used to show movement in the digestive
system (which may require ingestion of a
high-contrast liquid such as barium) and
the circulatory system (angiograms).
Slide 90
Ultrasound
Ultrasound is high-frequency sound waves
produced by a device called a transducer
that are reflected back to the transducer
by internal body structures.
Slide 91
Ultrasound
Ultrasound is high-frequency sound waves
produced by a device called a transducer
that are reflected back to the transducer
by internal body structures.
Slide 92
Ultrasound
Ultrasound is used to study soft tissues and
organs, especially the heart
(echocardiograms) and especially during
pregnancy.
Because the presence of gas can distort
images, ultrasound is not often used for
imaging the respiratory or digestive
systems.
Slide 93
Magnetic Resonance Imaging
(MRI)
Magnetic Resonance Imaging (MRI) is a
technique that uses strong magnets and
radio waves that interact with the
hydrogen atoms in your body (esp. in
water). A computer is used to construct
an image from the signal received from the
atoms.
Slide 94
Magnetic Resonance Imaging
(MRI)
MRI is used to image the structure and
function of the brain, heart, soft tissue, and
the inside of bones; to diagnose cancers,
brain diseases, and problems with the
circulatory system.
But it is also extremely expensive and the
availability of machines/technicians is
limited.
Slide 95
Positron Emission Tomography
(PET)
PET scans are a type of nuclear medicine is
which a patient is given a radioisotope that
emits positron radiation; the radioisotope
is attached to a chemical absorbed by
certain tissues or organs.
It is used to detect cancers,
heart disease,
and some brain disorders
(such as Alzheimer’s).
Slide 96
• End!!!!
SNC2 Biology Review
Slide 2
What is an Organism?
• An organism is a living thing. It is easy to
recognise a living thing, but not so easy to
define it. Animals and plants are
organisms, obviously. Organisms are
a biotic, or living, part of the environment.
Rocks and sunshine are parts of the nonliving environment abiotic.
Slide 3
Know the difference between
•
Quark: Simply energy. Can’t be seen under any microscope.
Atom: Made from quarks. Has protons, neutrons. These make molecules.
Molecule: These are made from Atoms. Examples of molecules are: Hydrogen,
Oxygen.
Organelle: Made of molecules and are the small organs in each cell. Examples in
animal cells are: Nucleus, Ribosome, Lysosome.
Cell: Made up of organelles. Cells are the building blocks of life.
Tissue: Made from similar cells. Each organ has specific types of cells that make that
particular organ and its parts.
Organ: Similar types of tissue (example muscle tissue, heart tissue) makeup an
organ.
Organ System: Organs that work together to help an organism execute a specific
function (breathing, thinking, etc) are part of an organ system.
Organism: An organism is the person/thing.
Slide 4
Nucleus
• The nucleus is the large
control centre of a cell,
directing all of the cell's
activities.
• Chromosomes that
contain your DNA are
stored in this organelle.
• The nucleus is separated
from the rest of the cell by
the nuclear membrane.
Slide 5
Ribosome
• Found on the
endoplasmic
reticulum or free in
the cytoplasm.
• Proteins are made
in this organelle.
Slide 6
Mitochondria
• The mitochondria is
sometimes referred to as
the powerhouse of the
cell.
• Mitochondria are largely
responsible for providing
the cell with energy from
glucose (sugar) through a
process called cellular
respiration.
Slide 7
Golgi Bodies
• Golgi bodies collect and
process materials to be
removed from the cell.
• They also make and
secrete mucus.
• Cells that secrete a lot of
mucus, such as cells
lining the intestine, have
many Golgi bodies.
Slide 8
Endoplasmic Reticulum
• The endoplasmic
reticulum is a threedimensional network of
branching tubes and
pockets.
• It extends throughout the
cytoplasm from the
nuclear membrane.
• These fluid-filled tubes
transport materials, such
as proteins, through the
cell.
Slide 9
Chloroplast
• Looks like: green stacks
of membranes that
contain chlorophyll
• Job: perform
photosynthesis (convert
sunlight into energy)
Slide 10
Vacuole
• Looks like: sac-like
organ. HUGE in plant
cells
• Job: stores water, food,
and waste
Slide 11
Vesicles
• A vesicle can be
seen as a bubble of
liquid within a cell.
• It is a small
membrane-enclosed
sack that can store
or transport
material.
Slide 12
Cell Membrane
• Looks like: layered
membrane surrounding the
cell but inside of the cell wall
• Job: “the regulator”-controls what
comes in and out of the cell,
protects, and supports the cell
Slide 13
Cell Wall
• Looks like: thick layer outside the plasma membrane
• Job: structure and support
Slide 14
Nuclear Membrane
Slide 15
What is the Cell Cycle?
As eukaryotic cells grow and divide, they pass
through a cell cycle that consists of 3 stages:
• Interphase
• Mitosis (cell division)
• Cytokinesis (cell division)
Slide 16
What happens?
Slide 17
STAGE of CELL CYCLE
Slide 18
Stage 1: Interphase
• Interphase is the longest stage of the cell cycle
• The cell performs its normal functions and, in
preparation for cell division, duplicates its genetic
material (DNA)
Slide 19
Slide 20
Stage 2: Cell Division - Mitosis
Consists of 4 phases:
Prophase
Metaphase
Anaphase
Telophase
Slide 21
Mitosis Phase 1:Prophase
• DNA compacts into
visible form as
chromosomes
• Each chromosome
contains two strands
called sister chromatids.
• Sister chromatids are
held together by a
centromere
• The nuclear membrane
breaks down
Slide 22
Mitosis Phase 2: Metaphase
• Chromosomes line up
in the middle of the
cell.
Slide 23
Mitosis Phase 3: Anaphase
• The centromere splits
and sister chromatids
separate.
• They are now called
daughter
chromosomes.
• They move to
opposite ends of the
cell, pulled by spindle
fibres
Slide 24
Mitosis Phase 4: Telophase
• Final phase of
mitosis.
• Chromosomes stretch
out and are no longer
visible.
• A new nuclear
membrane forms
around each group of
daughter
chromosomes.
Slide 25
Stage 3: Cell Division - Cytokinesis
• Final stage of cell division
and cell cycle
• The cytoplasm divides
and two genetically
identical cells are formed.
In a plant cell, a plate
develops into a new cell
wall
• In an animal cell, the cell
membrane is pinched off
in the centre
Slide 26
Plant vs Animal (Cytokinesis)
• In a plant cell, a plate develops into a new
cell wall
• In an animal cell, the cell membrane is
pinched off in the centre forming two
membranes,
Slide 27
Plant vs. Animal Cells
There are three main differences between
plant and animal cells:
1. Plant cells have a
cell wall, Animal
Cells do not
Slide 28
Plant vs. Animal Cells
2. Plant cells have
chloroplasts and
Animal Cells do not
Slide 29
Plant vs. Animal Cells
3. Plant cells have
larger vacuoles
(storage spaces)
Slide 30
Plant vs. Animal Cells
Plant Cells
1.Chloroplasts
2.Cell wall
3.Large
vacuole
Animal Cells
1.No Chloroplasts
2.No Cell wall
3.Small Vacuole
Slide 31
Plant vs. Animal Cells
Different Shapes (Plants are rectangles, and Animals are round)
Slide 32
Stages of Pregnancy and
Development
Fertilization
Embryonic development - Cleavage
Fetal - Differentiation
Growth – Development
Childbirth
Slide 33
Fertilization
The egg is viable for 12 to 24 hours after ovulation
Sperm are viable for 12 to 48 hours after ejaculation
Sperm cells must make their way to the uterine tube for
fertilization to be possible
Slide 34
ZYGOTE
1. The sperm and egg join to form a zygote: the first
cell of a new individual.
2. Zygote results of the fusion of DNA from sperm and
egg
2. Fertilization occurs in the Fallopian Tubes
3. The zygote begins rapid mitotic cell division
4. Beginning of human development
Slide 35
Differentiation
EMBRYO
0.5 cms
20 days after fertilization
•Embryo begins to form organs during
the third week.
•Cannot tell if it is human or other
vertebrate. Tall visible.
Slide 36
Differentiation
EMBRYO
1 months
0.6 cms
• Ears, nose and eyes not visible
• Small arm and leg buds, backbone seen
• Heart beats.
Slide 37
Differentiation
FETUS •
2 months
•
3 cms
During the second month most of the major
organ systems form, limb buds develop.
Limbs distinct with fingers and toes bones
begin to form, eyes far apart.
• The embryo becomes a fetus by the seventh
week.
Slide 38
Differentiation
All organ systems are
formed by the end of the
eighth week
Activities of the fetus are
growth and organ
specialization
A stage of tremendous
growth and change in
appearance
Fetus at nine weeks
3 cm
Slide 39
Differentiation
FETUS
2 months
3 cms
•Beginning the eighth week, the sexually
neutral fetus activates gene pathways for
sex determination, forming testes in XY
fetuses and ovaries in XX fetuses.
•External genitalia develop.
Slide 40
Developmental Aspects of the
Reproductive System
Gender is determined at fertilization
Males have XY sex chromosomes
Females have XX sex chromosomes
Gonads do not begin to form until the
eighth week
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide
Slide 41
Four Basic Kinds of Tissues
• Epithelial Tissue
• Connective Tissue
• Muscle Tissue
• Nervous Tissue
Slide 42
Epithelial Tissue
• Epithelial Tissue Locations:
– Covers the body
– Lines the cavities, tubes, ducts and blood
vessels inside the body
– Covers the organs inside body cavities
• Epithelial Tissue Functions:
– Protection from physical & chemical injury,
– Protection against microbial invasion,
• Examples: Skin, small intestine
Slide 43
Connective Tissue
• Connective Tissue:
– Most abundant & widely distributed tissue
• Connective Tissue Functions:
– Connects, binds and supports structures,
• Tendons, ligaments, etc.
– Protects & cushions organs and tissues,
– Insulates (fat) and
– Transports substances (blood).
Example: Bone and Blood.
Slide 44
Muscle Tissue
• Muscle Tissue:
– Associated with the bones of the skeleton, the heart and in the
walls of the hollow organs of the body.
• Muscle Tissue Functions:
– Movement
– Locomotion
– Maintains posture
– Produces heat
– Facial expressions
– Pumps blood
– Peristalsis
Example: arm, stomach, heart
Slide 45
Nervous Tissue
• Nervous Tissue:
– Main component of the nervous system,
ie., brain, spinal cord & nerves.
• Nervous Tissue Functions:
– Regulates & controls body functions
– Generates & transmits nerve impulses
– Supports, insulates and protects impulse generating neurons.
There are three types of neurons,
sensory neurons
motor neurons.
connector neurons
Slide 46
Cell Specialization
• All cells carry the same DNA
information but they do not
perform the same functions and
may not look the same.
• All cells start their lives as identical
cells called stem cells.
• The process of a cell becoming a
particular type of cell is called cell
differentiation.
Slide 47
• Groups of cells that function together and are specialized
for common tasks are called tissues.
• In simple terms, they are groups of cells that work
together to do the same job
Slide 48
Human Organ Systems
Slide 49
Levels of Organization
Remember, the human body is organized in several levels,
from the simplest to the most complex. . .
Cells – the basic unit of life
Tissues – clusters of cells performing a similar function
Organs – made of tissues that perform one specific
function
Organ Systems – groups of organs that perform a
specific purpose in the human body
***The purpose of the 11 organ systems is for the human body
to maintain homeostasis.
Slide 50
Homeostasis
• Homeostasis is: The ability or tendency
of an organism or cell to maintain internal
equilibrium by adjusting its physiological
processes.
Slide 51
The 11 Human Body Systems
The 11 human body systems are as follows:
-- nervous system
-- integumentary system
-- respiratory system
-- digestive system
-- excretory system
-- skeletal system
-- muscular system
-- circulatory system
-- endocrine system
-- reproductive system
-- lymphatic (immune) system
Slide 52
The Digestive System
Purpose: to convert food particles into simpler
micromolecules that can be absorbed into the
bloodstream and used by the body
Major Organs and their Functions:
Mouth – to chew and grind up food
-- saliva also begins the chemical breakdown
Esophagus – pipe connecting mouth to stomach
Stomach – secretes an extraordinarily strong acid (pH = 2) that
leads to breakdown of food
-- once the food is broken down in the stomach and
mixed with digestive juices, it is called chyme
Slide 53
Pancreas – produces the hormone insulin that regulates
blood
sugar levels
-- also help neutralize stomach acid
Liver – produces bile, which breaks down fats in foods
Gallbladder – pouch-like organ that stores bile for future use
Small Intestine – after digestion is complete, the chyme
enters the small intestine where it is absorbed into the
bloodstream
-- the chyme is propelled along by folded surfaces
called villi, on the intestine
Large Intestine – removes water from the chyme and gets the
waste ready for excretion
Slide 54
The Digestive System
Slide 55
The Respiratory System
Purpose: to provide the body with a fresh supply of oxygen
for cellular respiration and remove the waste product carbon
dioxide
Major Organs and Their Functions
Nose – internal entry and exit point for air
Pharynx – serves as a passage way for both air and food at
the back of the throat
Larynx – your “voicebox”, as air passes over your vocal
chords, you speak
Trachea – the “windpipe”, or what connects your pharynx to
your lungs
-- a piece of skin, called the epiglottis, covers the
trachea when you swallow, preventing food from
entering
Slide 56
Bronchi – the two large passageways that lead from the
trachea to your lungs (one for each lung)
-- the bronchi are further subdivided into bronchioles
-- eventually, the further subdivisions lead to tiny air
sacs called alveoli
-- alveoli are in clusters, like grapes
-- capillaries surrounding each alveolus is where
the exchange of gases with the blood occurs
The diaphragm is the muscle that causes you to breath
-- hiccups are involuntary contractions of the
diaphragm
Slide 57
Image of the Respiratory System
Slide 58
The Circulatory System
Purpose: to deliver oxygenated blood to the various cells and
organ systems in your body so they can undergo cellular
respiration
Major Organs and Their Functions
Heart – the major muscle of the circulatory system
-- pumps blood through its four chambers (two
ventricles and two atria)
-- pumps deoxygenated blood into the lungs, where it
gets oxygenated, returned to the heart, and then
pumped out through the aorta to the rest of the body
-- valve regulate the flow of blood between the
chambers
Slide 59
Arteries – carry blood away from the heart and to the major
organs of the body
Veins – carry blood back to the heart away from the major
organs of the body
Capillaries – small blood vessels where gas exchange occurs
Blood – the cells that flow through the circulatory system
-- red blood cells contain hemoglobin, an iron-rich
protein that carries oxygen
-- white blood cells function in the immune system
-- platelets help in blood clotting
Spleen – helps to filter out toxins in the blood
Slide 60
Image of the Circulatory System
Slide 61
THE HUMAN HEART
The human heart
consists of 4
chambers
there are two types of
chambers: the atrium
and the ventricle
there are two of each
type in the heart
the heart weighs a
mere 300 grams
Slide 62
HEART VALVES
The human heart contains valves which
prevent blood from flowing back into the
heart chambers after it has contracted
atrioventricular valves are found
between the atrium and ventricle of
each side of the heart
semilunar valves are found in the
arteries leaving the heart to prevent
blood from flowing back into the
ventricles
Slide 63
HEART AT WORK
Each minute of the
day the heart pumps
5 litres of blood
each time the heart
beats it sends
deoxygenated blood
to the lungs and
oxygenated blood to
the body
Slide 64
THE HEART TO THE LUNGS
Blood enters the right
atrium of the heart via
two large veins: the
superior vena cava
and the inferior vena
cava
blood exits the right
ventricle of the heart
through the
pulmonary artery to
the lungs
Slide 65
Direction of Blood
Slide 66
THE HEART TO THE BODY
(Circulatory and Respiratory)
Blood reenters the left
artrium of the heart
via the pulmonary
vein
blood on the left side
of the heart is
oxygenated and is
pumped into the body
by the left ventricle
through the aorta
Slide 67
What is cancer?
• Caner is defined as the continuous
uncontrolled growth of cells.
• A tumor is a any abnormal proliferation of
cells.
• Benign tumors stays confined to its original
location
• Malignant tumors are capable of invading
surrounding tissue or invading the entire body
• Tumors are classified as to their cell type
• Tumors can arise from any cell type in the
body
Slide 68
What is Melanoma?
1. A type of skin cancer
2. Some risk factors
include:
1. Sun exposure depleting ozone layer
2. Presence of many or
unusual moles
3. Skin types
4. Genetics
predisposition
Slide 69
skin
benign
malignant
Slide 70
Slide 71
Diagnosis and
Medical Imaging
Technology
SNC2D
Slide 72
Diagnosis
• The interdependence of our organ systems can
sometimes make it difficult to pinpoint the source
of a medical problem.
• Doctors are trained to look for symptoms that
are characteristic of specific problems.
Slide 73
Diagnosis
• The interdependence of our organ systems can
sometimes make it difficult to pinpoint the source
of a medical problem.
• Doctors are trained to look for symptoms that
are characteristic of specific problems (e.g.
swollen lymph nodes are a symptom of
infection).
Slide 74
Tools of the Trade
To collect information about what’s going on
inside the body, doctors may use devices
like the stethoscope (to listen to the heart
and lungs)
Slide 75
Tools of the Trade
To collect information about what’s going on
inside the body, doctors may use devices
like the stethoscope (to listen to the heart
and lungs) and a sphygmomanometer (to
measure blood pressure).
Slide 76
Tests of the Trade
Doctors may also order tests of material
collected from the body (such as blood
and urine) which may be analyzed by a
separate lab.
E.g. Blood may be tested to determine the levels
of red blood cells, white blood cells, sugar, and
hormones – the chemicals that carry messages
through the body to regulate the functioning of
organs.
Slide 77
Medical Imaging Technologies
Diagnostic imaging tests can provide
doctors with even more information: an
actual visual picture of the structure and
functioning of organs.
However, these technologies are often
expensive, and the effectiveness of each
technology is limited by its properties.
Slide 78
Endoscopy
An endoscope is a thin, flexible tube that
has a bright light and a video camera that
can be used to image the digestive tract,
as in a colonoscopy.
Slide 79
Endoscopy
An endoscope is a thin, flexible tube that
has a bright light and a video camera that
can be used to image the digestive tract,
as in a colonoscopy.
Slide 80
Thermography
In thermograms, infrared light cameras are
used to diagnose problems with
circulation.
Normal
Raynaud’s syndrome
Slide 81
X-Rays
X-rays are high-energy electromagnetic
radiation that can easily penetrate soft
tissues but cannot easily penetrate bone.
Slide 82
X-Rays
X-rays are used to check for cancers (e.g.
mammograms), to diagnose problems in
the circulatory and respiratory systems,
and to check for broken bones.
They are quick, painless, and non-invasive
but exposure to x-rays can damage cells
and increases cancer risk.
Slide 83
Body Scanners
Note that this is also true for the body
scanners that are used at airports,
especially the new “naked body scanners.”
Slide 84
Body Scanners
Since the radiation emitted by these body
scanners is absorbed at the level of the
skin, it is your skin cancer risk that is most
increased – and the scans cannot find
anything concealed in any body cavity.
Slide 85
Body Scanners
Since the radiation emitted by these body
scanners is absorbed at the level of the
skin, it is your skin cancer risk that is most
increased – and the scans cannot find
anything concealed in any body cavity.
Also, like most x-rays, they do not show
contrast that may be used to identify soft
materials (like plastics and chemical
explosives).
Slide 86
Body Scanners
Since the radiation emitted by these body
scanners is absorbed at the level of the
skin, it is your skin cancer risk that is most
increased – and the scans cannot find
anything concealed in any body cavity.
Also, like most x-rays, they do not show
contrast that may be used to identify soft
materials (like plastics and chemical
explosives).
In other words, they’re completely
Slide 87
Computed Tomography
Computed tomography
(CT) scans, also called
computer-assisted
tomography (CAT)
scans, use x-rays to
produce images at
different angles
through the body so
that a 3D image can be
constructed.
Slide 88
Computed Tomography
CT scans may be used to diagnose cancers,
skeletal abnormalities and vascular
diseases (affecting blood vessels).
But since CT scans use x-rays, they also
increase your cancer risk.
Slide 89
Fluoroscopy
Fluoroscopy is a technique in which a
continuous beam of x-rays is used to
produce moving images.
It is used to show movement in the digestive
system (which may require ingestion of a
high-contrast liquid such as barium) and
the circulatory system (angiograms).
Slide 90
Ultrasound
Ultrasound is high-frequency sound waves
produced by a device called a transducer
that are reflected back to the transducer
by internal body structures.
Slide 91
Ultrasound
Ultrasound is high-frequency sound waves
produced by a device called a transducer
that are reflected back to the transducer
by internal body structures.
Slide 92
Ultrasound
Ultrasound is used to study soft tissues and
organs, especially the heart
(echocardiograms) and especially during
pregnancy.
Because the presence of gas can distort
images, ultrasound is not often used for
imaging the respiratory or digestive
systems.
Slide 93
Magnetic Resonance Imaging
(MRI)
Magnetic Resonance Imaging (MRI) is a
technique that uses strong magnets and
radio waves that interact with the
hydrogen atoms in your body (esp. in
water). A computer is used to construct
an image from the signal received from the
atoms.
Slide 94
Magnetic Resonance Imaging
(MRI)
MRI is used to image the structure and
function of the brain, heart, soft tissue, and
the inside of bones; to diagnose cancers,
brain diseases, and problems with the
circulatory system.
But it is also extremely expensive and the
availability of machines/technicians is
limited.
Slide 95
Positron Emission Tomography
(PET)
PET scans are a type of nuclear medicine is
which a patient is given a radioisotope that
emits positron radiation; the radioisotope
is attached to a chemical absorbed by
certain tissues or organs.
It is used to detect cancers,
heart disease,
and some brain disorders
(such as Alzheimer’s).
Slide 96
• End!!!!