9.1 Circulatory Systems

Question 1

what is the circulatory system

Answer 1

a system of blood vessels with a pump and valves to ensure one-way flow of blood

Question 2

describe the single circulation of a fish

Answer 2

-heart of a fish has 2 chambers (atrium and ventricle)
-blood passes through the heart once to complete a full circuit through the body of the fish
- deoxygenated blood from the body capillaries move into the two chambered heart and then reaches the gill capillaries where oxygen is absorbed into the blood (gill circulation). the oxygenated blood moves from the gill capillaries to the body capillaries to complete one circuit (systemic circulation)

Question 3

describe the double circulation of a mammal

Answer 3

-mammalian heart has 4 chambers
-blood passes through the heart twice every one circuit of the body
-deoxygenated blood enters the right atrium via vena cava then moves into right ventricle. next deoxygenated blood pumped by the right atrium to lung by pulmonary artery (pulmonary circulation). gas exchange happens at lungs. oxygenated blood entered left atrium via pulmonary vein then moves to left ventricle. oxygenated blood pumped by left ventricle to body via aorta (systemic circulation). body cells use oxygen causing blood to become deoxygenated. blood returns to the heart.

Question 4

advantages of double circulation

Answer 4

-allows oxygen and glucose to be delivered faster and more efficiently through the blood since a double circulation maintains a high blood pressure than single circulation system