Circulation• Your body

resembles a large roadmap, There are routes or “arteries” that take you downtown to the “heart” of the city.

Functions• Transport oxygen and carbon

dioxide• Distribute nutrients• Transport wastes• Distribute hormones• Regulate body temperature

3 Major Parts of the Circulatory system

•Blood Vessels - routes blood travels

•Heart – pumps or pushes blood through body

•Blood – carries important “ *stuff ” through body

* Stuff – includes oxygen, food, & waste

One Way Streets

Blood Vessels

• Blood Vessels resemble very long and skinny tunnels that are all through your body.

Blood Vessels• Arteries/arterioles – have smooth

muscle in walls, take blood away from the heart. http://learn.fi.edu/learn/heart/vessels/arteries.html

• Capillaries – very small, place where most gas exchange occurs http://learn.fi.edu/learn/heart/vessels/capillaries.html

• Veins/venues – have valves, no muscle, take blood toward the heart

• http://learn.fi.edu/learn/heart/vessels/veins.html

The Heart

Lub

If you listen to your heartbeat, it makes a lub dub sound.

The lub is when blood is pushed out of the heart into the body and the dub is the reloading of the heart with more blood ready to push it out to the body

Dub

The Heart

Cardiac cycleSystole – ventricle

contractionDiastole –

relaxation of all chambers following contraction of atria

Blood’s Path Through the Heart - Deoxygenated

1. Vena cava2. Right atrium3. Right ventricle4. Pulmonary

Arteries5. Lungs

Blood’s Path Through the Heart - Oxygenated

6. Lungs7. Pulmonary Veins8. Left atrium9. Left ventricle10.Aorta11.Body

Influence on Heart Rate

• Nervous system

• Hormones

Functions of Blood

• Transport– Nutrients– Gasses– Hormones– Waste Products

• Immune Response

Blood Composition

• Plasma 55-60%• Red blood cells – carry oxygen• White blood cells - immunity• Platelets – clotting

***Blood is mostly saltwater!***