Cardiac cycle

Question 1

What are the three stages of the cardiac cycle?

Answer 1

Atrial systole, Ventricular systole, and cardiac diastole

Question 2

What happens during atrial systole?

Answer 2

AV valves open and SL valves close

Question 3

What happens during ventricular systole?

Answer 3

Av valves close and SL valves open

Question 4

What happens during cardiac diastole?

Answer 4

AV valves open and SL valves close

Question 5

What are the functions of the Valves?

Answer 5

Av valves separate atria from the ventricle
Av valves open when atrial walls contract allowing blood to flow to ventricles
Av valves close during ventricular systole to prevent backflow of blood
When ventricles relax semilunar valves close to prevent the backflow of blood

Question 6

What are the factors affecting the heart rate?

Answer 6

Physical exercise
Age
Gender
Drugs
Stress or excitement

Question 7

How to calculate the heart rate?

Answer 7

Number of pulses over minutes

Question 8

What is a pulse?

Answer 8

A pulse is when the elastic tissues in the arteries can expand and recoil

Question 9

Where can we measure a pulse?

Answer 9

At the neck and the wrist

Question 10

What is the artery’s function?

Answer 10

To send blood away from the heart to other body organs and to carry the oxygenated blood

Question 11

What is the Vein’s function?

Answer 11

To carry blood to the heart from the body cells and to carry the deoxygenated blood

Question 12

What is the capillaries’ function?

Answer 12

To connect arteries and veins and to make a place where the exchange of gases and many more elements btwn blood and the cells

Question 13

What does the artery consist of?

Answer 13

Tunica externa tunica media and tunica interna

Question 14

What is the tunica externa made of?

Answer 14

It is made up of tough collagen fibers that withstand high BP and prevent rupturing

Question 15

What does the tunica media contain?

Answer 15

Smooth muscles and elastin fibers

Question 16

What are the smooth muscles for in the tunica media?

Answer 16

To withstand high bp and to change the diameter accordingly

Question 17

What are the elastin fibers for in the tunica media?

Answer 17

To stretch during ventricular systole and recoil during ventricular diastole and to accommodate the high BP

Question 18

What is the tunica interna made up of?

Answer 18

1 layer of endothelial cells which are smooth to reduce friction and to increase ease of blood flow

Question 19

What do veins have?

Answer 19

A valve with a larger lumen a thin middle layer and elastic fibers with smooth muscles

Question 20

What are the features of a vein?

Answer 20

They have no pulse nor stretching or recoiling but they do have a low pressure therefore they have thin walls

Question 21

What is a capillary?

Answer 21

A capillary is 1 cell wide and is made out of endothelial cells

Question 22

What are the features of a capillary?

Answer 22

Very thin walls that allow rapid diffusion and they are very branched and have a small diameter

Question 23

How is pressure calculated?

Answer 23

Ventricular systole over ventricular diastole

Question 24

How is blood pressure measured?

Answer 24

By using a stethoscope and a sphygmomanometer

Question 25

Why does blood pressure vary during the day?

Answer 25

Constriction and dilation of the blood vessels and the way the heart works