Systems Review
Integumentary System:
 Organsskin, hair, nails, sweat glands, sebaceous glands
 Functionphysical barrier so first line of defense; controls body temperature;
prevents fluids from leaving the body
Skeletal System:
 Organsbones
 Functionsupports the body; protects internal organs; provides a place for
muscle attachment; makes blood cells
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exoskeletons are found on the outside of the body (ex: insects)
endoskeletons are found on the inside of the body
the place where two bones meet are called joints and allow the skeleton to move
ligaments are bands of connective tissue that connect the two bones that form
joints
Muscular System:
 Organsmuscles
 Functionmovement
Muscles attach to the skeleton and allow
you to move the body. Skeletal muscles
usually work in pairs. One muscle
contracts while the other relaxes to create
movement (ex: the biceps muscle contracts
to bend the elbow while the triceps muscle
is relaxed). To “undo” the movement, the
1st muscle relaxes and the 2nd muscle
contracts (ex: the biceps muscle relaxes
and the triceps muscle contracts to
straighten out the arm).
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there are three types of muscles:
o skeletal muscle: this is voluntary (can be controlled) and makes up the
muscles that move the skeleton
o cardiac muscle: this is involuntary (can not be controlled) and makes up
the heart muscle
o smooth muscle: this is involuntary and is found in the walls of the body
organs (ex: stomach, intestines, blood vessels)
Cardiovascular System:
 Organsheart, arteries, veins, capillaries
 Functioncarries oxygen from the lungs to all the body cells and removes wastes
The blood flows from the heart to the
lungs where it receives oxygen. The
newly oxygenated blood travels back
to the heart and then travels out of
the heart to the body. As the blood
travels through the body, it loses its
oxygen. The deoxygenated blood then
returns to the heart and the cycle
begins again.
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arteries are the vessels that carry blood away from the heart
capillaries connect arteries and veins and are the smallest vessels in the body; this
is where substances enter and leave the blood stream
veins are the vessels that carry blood back to the heart
this system is a closed system, because blood does not leave the vessels
in an open system, blood leaves the vessels and enters open spaces that surround
the body organs; simple organisms like insects have open systems
Lymphatic System:
 Organslymph vessels, spleen, tonsils, thymus, lymph nodes
 Functionreturns fluid lost by cardiovascular system to the heart; cleans this
fluid and works with the immune system to destroy bacteria and other foreign
invaders
The lymph vessels carry lymph (fluid that has leaked
out of the cardiovascular system) back to the heart. As
lymph is carried through the system, it goes through
the lymph nodes. The nodes help clean the lymph.
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Respiratory System:
 Organsnose, pharynx, larynx, trachea, lungs
 Functionprovides oxygen, removes carbon dioxide, voice production
Air passes through the nose, pharynx,
larynx, and trachea. The trachea divides
into smaller tubes called bronchi. These
tubes carry the air into the lungs into
structures called alveoli. Here is where
the oxygen in the air enters the
bloodstream and the carbon dioxide exits.
Digestive System:
 Organsmouth, teeth, tongue, pharynx (throat), esophagus, stomach, small
intestine, large intestine, salivary glands, liver, pancreas, gallbladder
 Functionbreaks down food to provide nutrients and removes solid wastes
Digestion of food starts in the mouth. Saliva helps to
break down simple sugars. The tongue initiates
swallowing and food is pushed into the esophagus.
Food goes down into the stomach. The stomach
“churns” the food and helps break it down into
smaller pieces. The food then moves into the small
intestine where the nutrients leave this system and
enter the blood. The remaining contents move into the
large intestine and rectum and are eliminated from
the body through the anus. The liver, gallbladder and
pancreas produce substances that help with the
chemical breakdown of food.
Immune System:
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Organsno organs; just cells
Functionprotects against foreign invaders
Pathogens (ex: bacteria)
enter tissues through a
wound. They are attacked
by macrophages at the
infection site. Antigens
B cell
(proteins) of the pathogen
Macrophage
are displayed on the
surface of the
macrophage. Helper T
cells have receptor sites
that recognize and bind to
the antigens on the
macrophage. B cells can
bind to antigens directly.
Helper T cells bind to
T cell
Plasma cells
antigens on B cells
T cells release chemicals
that cause B cells to
produce plasma cells.
Antibodies
Each plasma cell secretes
more than 2000 antibodies
per second in the blood.
Memory B cells and antibodies remain in the blood and respond to future invasions by
the same pathogen.
Pathogen
Endocrine System:
 Organsovaries, testes, thyroid, adrenals, pituitary, thymus, pancreas,
parathyroids
 Functionslow-acting control system; makes hormones
The glands of this system make hormones that
must enter the bloodstream to reach the organ that
they will act upon. Because the hormones must
travel through the bloodstream, this system takes
time to cause a reaction in the body.
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Reproductive System:
 Organsfemales: ovaries, vagina, uterus, cervix, Fallopian tubes
males: penis, testes, urethra, ductus deferens
 Functionmakes hormones; produce offspring
Fallopian tube
ductus deferens
ovary
uterus
penis
cervix
vagina
urethra
testis
Urinary System (a.k.a. Excretory System):
 Organskidneys, ureter, bladder, urethra
 Functioncleans the blood and removes liquid wastes from blood
The kidneys filter the blood and remove wastes.
These wastes form the urine. Urine moves from the
kidneys through the ureters and into the bladder
where it is stored. Urine leaves the body through the
urethra.
Nervous System:
 Organsbrain, special
senses, spinal cord, nerves
 Functionvision, hearing,
taste, fast-acting control
This system is responsible for
controlling all of the other body
systems. The organs of special
sense (ex: eyes, ears) take in
information about the
environment so that this system
can respond.
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sensory neurons receive information from the external and internal
environment and send it to the brain (ex: signal from the skin to the brain that
lets the brain know it is cold outside)
motor neurons sends signals from the nervous system to the body to cause a
response (ex: signal from the brain to the muscles to cause “shivering” in
response to the cold)
Reflex
o an automatic response to a stimulus
o the nerve signal travels to the spinal cord using a sensory neuron
(nerve cell)
o the spinal cord sends a signal using a motor neuron to cause a response
o the spinal cord also sends a signal to the brain so that it is aware of the
stimulus
o because the motor signal does not come from the brain, the reaction is
much faster
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