Organ Systems
Levels of Organization
Atom
Molecule
Human Organ Systems
HOMEOSTASIS
Each organ system works to
maintain HOMEOSTASIS
HOMEOSTASIS – Maintaining a
stable internal environment
Biology GVC #7
Describe the relationship
between structure and
function of organ
systems in plants and
animals.
Skeletal System• Supports the body
and gives it shape
• Protects internal
organs
• Produce Blood Cells
• Stores Minerals
Role in HOMEOSTASIS: maintains correct levels
of minerals
Function:
Organs/Structures in the Skeletal System
Bones – Hard and Rigid, form
main skeleton Ligaments – band of fibrous connective
tissue, holds bones together
Cartilage – dense connective tissue,
usually found in joints
Bone Marrow –
Where red blood
cells are made
Joints- Places where 2 or more bones meet
Muscular System
Function: Provide movement and heat
production.
Role in HOMEOSTASIS: move body and maintain
body temperature
Organs/Structures:
Muscles – organs composed of muscle cells (fibers)
that can contract to move parts of the body
Tendons – Connect muscles to bones
Types of Muscles
Cardiac:
• Found only in heart
• Contracts to pump blood
• Has A LOT of mitochondria
• Involuntary
Smooth:
• Found in walls of internal organs
• Helps organs carry out functions
• Involuntary
Skeletal:
• Found attached to bones
• Move skeleton and other body parts
• Voluntary
IntegumentaryFunction: Outer covering of your
body, provides protection
Organs/Structures:Skin – Largest organ,
provides protection,
controls body temperature
Hair – made of keratin,
controls body temperature
Nails – made of keratin,
protect fingertips and toes
Role in HOMEOSTASIS: Protection, maintain body
temperature, sense of touch
Nervous SystemFunction: Carries electrical messages
throughout the body
Organs/Structures:Brain – Control center, has 100
Billion neurons
Spinal Cord – thin bundle of
nervous tissue going from brain
to pelvis
Nerves – carry signals from
spinal cord to all parts of body
Role in HOMEOSTASIS: Allows organism to respond
quickly to changes
Nerve cell (Neuron)1. Electrical
signal starts in
Dendrite and
travels along the
Axon .
2. When the
signal reaches
the Axon
Terminal it jumps
to the Dendrite
of the next
neuron.Axon – The long, slender part of a
nerve cell; it is the main carrier of
the electrical signalBrain Games
EndocrineFunction: Produces hormones
Organs/Structures:Pineal Gland Adrenal Gland
Hypothalamus Pancreas
Pituitary Gland Testes
Thyroid Gland Ovaries
Thymus
Role in HOMEOSTASIS: Regulates metabolism,
growth, body development
Circulatory System
Function: move materials around the
body (hormones, oxygen, waste, nutrients)
Role in HOMEOSTASIS: Allows substances to move
from one place to another
Heart – made of mostly
muscle tissue, pumps
blood through blood
vessels by contracting
(squeezing)
Blood Vessels – network of
tubes that carry blood
throughout body (arteries,
veins, capillaries)
Circulatory system
ARTERIES – Carry oxygenated
blood AWAY from the heart
very muscular
VEINS – Carry blood TOWARD
the heart;
have valves to prevent
backflow
CAPILLARIES – Connect small
arteries and veins;
exchange gases and other
substances
BLOOD is made up of Plasma (liquid), Red Blood
Cells (carry oxygen), White Blood Cells (immune
system), and Platelets (blood clotting).
Blood Flow Through Heart
Lungs
Body
Left
Ventricle
Left
Atrium
Right
Ventricle
Right Atrium
Animation of blood flow
Blood Flow through Body
Red:
Arteries
Blue:
Veins
Respiratory System
Function: Bring OXYGEN into the body and
release CARBON DIOXIDE out of the body
Main Organs/Structures:
• Nose/mouth• Larynx – voice box
• Trachea (windpipe)
• Lungs• Bronchi – branching
tube leading to each
lung
• Alveoli – clusters of air
sacs
• Diaphragm – muscle
that contracts to
make lungs expand
Respiratory
Role in HOMEOSTASIS: Gas exchange (Oxygen
in, Carbon Dioxide out)
Respiration – How do we breathe?
Respiration Animation
Gas Exchange
Animation
Digestion
Function: Break down food
and absorb nutrients
Organs/Structures:
Mouth – break down food
Esophagus -
Stomach – Mixes food with digestive enzymes to break
them apart
Pancreas – releases digestive enzymes and hormones
(insulin)
Liver – detoxify blood, make proteins, produce
chemicals to help digestion
Gall Bladder – stores bile (fluid that helps digest lipids)
Small Intestine – breaks down food with chemicals and
absorbs nutrients
Large Intestine – reabsorb water
Rectum – accumulates feces
Role in HOMEOSTASIS: Provides the body with necessary
nutrients and removes wastes
Urinary/ExcretionFunction: Filter wastes from body and control
water loss
Organs/Structures:
Kidneys – Filter wastes out of blood
Large Intestine – reabsorbs water
Liver – break down toxins in blood
Skin – eliminate excess water and salts
Lungs – exhale water vapor and CO2
Role in HOMEOSTASIS: Removes wastes from the body,
maintains steady water levels
Lymphatic (Immune System)Function: Destroys pathogens (micro-organisms
that cause disease)
Role in HOMEOSTASIS: Protects the body from disease and infection
Organs/Structures:Lymph Vessels – vessels that carry lymph through body
Lymphocytes – cells that destroy pathogens
Lymph – Fluid containing lymph, filters pathogens
Lymph Nodes – Structure that filters the lymph
Bone Marrow – Produces Lymphocytes
Thymus – Stores Lymphocytes
Spleen – Filters out pathogens and worn out blood cells
Tonsils – Trap pathogens