Unit 3


Circulatory System (D-C)

 •Transports molecules around the body

 • Is made up of the heart and blood vessels

 •Oxygen is transported to cells for respiration

 •Carbon Dioxide is transported to the lungs after it's made in respiration 
 •Nutrients transported from digestive system-cells 

1 of 7

Heart Structure (D-C)

 •Has four chambers - two at the top, two at the bottom 

 •Top two chambers-  the atria (recive blood)

 •Bottom two chambers - the ventricles ( pump blood) 

 •Made of tissues

 •Pumps blood around the body by contracting and relaxing

 •Oxygenated blood- left

 •Deoxygenated blood- right

 •To prevent back flow, valves open and close in the large arteries.

 •Valves found between the atria and the ventricle

2 of 7

Sides of the heart (B-A*)

 •Oxygenated blood leaves via the aorta - travels around the body- returns deoxygenated blood via the vena cava.

 •Oxygenated blood travels to the lungs in the pulmonary artery and returns to the heart in the pulmonary vein 

 •The pulmonary artery only artery to carry deoxygenated blood

 •The pulmonary vein only vein to carry  deoxygenated blood

3 of 7

Blood Vessels-Arteries (D-C)

 •Carries blood away from the heart

 •Carries blood under high pressure  

 •Has thick and elastic walls to stretch - high pressure

 •Coronary arteries - deliver blood to the heart

 •Pulmonary arteries - deliver blood to lungs

4 of 7

Blood Vessels-Veins (D-C)

 •Carries blood back to the heart

 •Carries blood under low pressure

 •Have valves to prevent back flow of blood - low pressure

 •Coronary vein  drains blood from the heart to the coronary sinus

 •Pulmonary vein - carries blood from the lungs to the left atrium of the heart

5 of 7

Blood Vessels-Capillaries (D-C)

 •Carries blood to cells 

 •One cell thick - easy diffusion

 •Needed for transport

6 of 7

Cholesterol and the heart (B-A*)


 •Can build up in blood vessels causing plaques

 The Heart:

 •If plaque blocks a coronary artery - heart attack

 •Stent - can be inserted in the coronary artery to keep it open

7 of 7


No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Circulation resources »