valves and vessels

Question 1

Valves open and close due to _______?

Answer 1

pressure change

Question 2

What is the role of the Atrioventricular valves?

Answer 2

prevents backflow
when ventricle pressure is higher than aortial.
ensures blood does not move to atria

Question 3

Name the three types of valves

Answer 3

Atrioventricular valve
Semi-lunar
pocket

Question 4

What is the role of the Semi-lunar valves?

Answer 4

open when pressure of ventricle exceeds aorta/pulmonary artery
occurs when ventricle walls recoil and relaxes

Question 5

Describe the structure of a pocket valve

Answer 5

tough, flexible fibrous tissue
cusp shaped
pressure greater on convex side = open
pressure greater on concave side = shut

Question 6

What is the role of a pocket valve?

Answer 6

occurs in veins to prevent the backflow of blood

Question 7

How long does one cycle take?

Answer 7

0.8s

Question 8

How long does it take for artia systole to occur?

Answer 8

0.1s

Question 9

How long does it take for ventricular systole to occur?

Answer 9

0.3s

Question 10

How long does it take for diastole to occur?

Answer 10

0.4s

Question 11

What does the second heart sound indicate?

Answer 11

the semi-lunar closing

Question 12

When does the pressure of the blood decrease?

Answer 12

as the heart relaxes/ diastole

Question 13

Why is the max pressure never 0?

Answer 13

the aorta elastic walls recoil

Question 14

Name the five parts that make up a blood vessel

Answer 14

tough fibrous outer layer
muscle layer
elastic layer
endothelium
lumen

Question 15

Name the function of the arteries

Answer 15

carry blood away from the heart to the arterioles

Question 16

Name the function of the arterioles

Answer 16

smaller arteries that control blood flow from arteries to capillaries

Question 17

Name the function of the capillaries

Answer 17

tiny vessels that link arterioles to veins

Question 18

Name the function of the veins

Answer 18

carry blood from capillaries back to the heart