Human Body Systems

Structures, Functions and Interdependence

SKELETAL SYSTEM

• Structures:– Bones - Tendons – Joints - Ligaments– Cartilage

• Functions:– Gives the body shape/support– Allows for movement at the joints– Protects vital organs – Creates blood cells

SKELETAL SYSTEM

MUSCULAR SYSTEM

MUSCULAR SYSTEM • Structures:

– Muscles– Most organs

• Heart, stomach, intestines, brain, tongue, diaphragm, etc.

• Functions:– Allows the body to move – Gives body shape and

strength

Systems Work Together…

1. Skeletal and Muscular System• Our muscles must be

connected to the skeletal system to allow for strength and movement.

• They both help protect our internal organs.

DIGESTIVE SYSTEM

DIGESTIVE SYSTEM • Structures:– Mouth– Esophagus– Stomach– Small/large intestines

• Functions:– Digestion = breakdown of food, chemically

and mechanically – Absorption = food is processed into a

usable source of energy – Defecating = getting rid of solid waste

Systems Work Together…2. Digestive and Muscular System• At the mouth, the muscles of the jaws

and tongue break food into pieces. • Muscles of the throat move food down the

esophagus. • In the stomach, churning

motions produced by muscles break food into smaller bits and mix it with stomach acid.

• Finally, muscular contractions of the intestine move food through the remainder of the digestive tract.

RESPIRATORY SYSTEM

RESPIRATORY SYSTEM

• Structures:– Trachea (windpipe)– Larynx (voice box)– Lungs – Diaphragm

• Functions:1. Respiration – to supply the blood

with oxygen by breathing (inhale oxygen and exhale carbon dioxide)

2. Vocalization – using your vocal cords to speak, sing, scream, etc.

3. Respiratory and Muscular Systems• The diaphragm is a muscle that

contracts (tightens) to allow air to enter the lungs. It then relaxes to push air out of the lungs.

• The vocal cords are a muscle and make sound as air passes through them.

• Respiration provides oxygen to the muscles so they can work. All cells need oxygen to function.

Systems Work Together…

CIRCULATORY SYSTEMAKA Cardiovascular System

If you stretched out all of your blood vessels, they

would circle the world 2.5 times!!!

CIRCULATORY SYSTEM

• Structures:– Heart– Blood – Blood Vessels

~ veins, arteries, capillaries • Functions:

o Circulation – movement of blood throughout the body

o Mailman - blood delivers oxygen to cellso Trash man - picks up and eliminates

waste from the cells

Systems Work Together…4. Respiratory and Circulatory Systems • Red blood cells move

around the body providing oxygen to the other cells.

• Red blood cells also pick up and remove carbon dioxide and water that cells create as waste.

NERVOUS SYSTEM

What other human body system does this remind

you of?

What are the similarities and differences between the 2 pictures of

the systems?

No, that is NOT

an alien!!!

NERVOUS SYSTEM • Structures:– Brain– Spinal Cord– Nerves

• Functions:1. Send electrical

signals to all other systems of the body.

2. Transmit information from the environment to the brain.

You want your dendrites to grow!!!

Systems Work Together…5. Nervous and all the

other systems • The brain controls

voluntary and involuntary muscle movement through electrical signals.• Voluntary – walking,

swimming, reading• Involuntary – breathing,

digesting, heart beat

• The signals are delivered through the spinal cord and nerves to tell the rest of the body what to do.