The circulatory system

Question 1

what are the four chambers of the heart?

Answer 1

right atrium, right ventricle, left atrium, left ventricle

Question 2

what do valves do?

Answer 2

prevent the blood from flowing backwards.

Question 3

Which ventricle has thicker walls and why?

Answer 3

The left ventricle has thicker walls to pump blood all the way around the body. (pumps blood at higher pressures)

Question 4

What is the journey of blood around the body?

Answer 4

Body tissues ➔ vena cava ➔ right atrium ➔ right ventricle ➔ pulmonary artery ➔ lungs ➔ pulmonary vein ➔ left atrium ➔ left ventricle ➔ aorta ➔ body tissues

Question 5

Which blood vessel carries oxygenated blood from the heart to the body?

Answer 5

Aorta

Question 6

Pacemaker cells are found in which chamber of the heart?

Answer 6

Right atrium

Question 7

What do the coronary arteries do?

Answer 7

Provide the heart muscle with oxygen and nutrients.

Question 8

What happens if the coronary arteries get blocked?

Answer 8

A heart attack.

Question 9

What type of heart do fish have?

Answer 9

Two chambered heart with single circulation

Question 10

How does blood circulate in mammals?

Answer 10

Four chambered heart with double circulation

Question 11

What does the right side of the heart do?

Answer 11

Receives deoxygenated blood from the body and pumps it to the lungs

Question 12

What does the left side of the heart do?

Answer 12

Receives oxygenated blood from the lungs and pumps it to the body

Question 13

What is the function of the septum in the heart?

Answer 13

Separates the two sides of the heart to prevent mixing of oxygenated and deoxygenated blood

Question 14

What are the two sets of valves in the heart?

Answer 14

• Atrioventricular valves
• Semilunar valves

Question 15

What is the function of the atrioventricular valves?

Answer 15

Separate the atria from the ventricles and prevent blood flowing back into the atria

Question 16

What is the name of the valve in the right side of the heart?

Answer 16

Tricuspid valve

Question 17

What is the name of the valve in the left side of the heart?

Answer 17

Bicuspid valve

Question 18

What happens when the ventricles contract?

Answer 18

Atrioventricular valves are pushed shut to prevent blood flowing back into the atria

Question 19

What prevents blood from flowing back into the heart from the arteries?

Answer 19

Semilunar valves

Question 20

How does deoxygenated blood flow into the heart?

Answer 20

Flows into the right atrium via the vena cava

Question 21

What happens to blood after it passes through the right ventricle?

Answer 21

It is pushed into the pulmonary artery through the semilunar valve

Question 22

What occurs during gas exchange in the lungs?

Answer 22

Blood moves through capillaries past alveoli

Question 23

How does oxygen-rich blood return to the heart?

Answer 23

Returns to the left atrium via the pulmonary vein

Question 24

What is heart rate measured in?

Answer 24

Beats per minute (bpm)

Question 25

What happens to heart rate during exercise?

Answer 25

It increases to supply working muscles with nutrients and oxygen

Question 26

What is angina?

Answer 26

Severe chest pains caused by restricted blood flow to cardiac muscle

Question 27

What can cause coronary heart disease?

Answer 27

* Poor diet * Stress * Smoking * Genetic predisposition * Age * Gender

Question 28

What lifestyle changes can reduce the risk of coronary heart disease?

Answer 28

* Quit smoking * Reduce animal fats in diet * Exercise regularly

Question 29

What is angioplasty?

Answer 29

A procedure where a balloon is inflated to flatten plaque against artery walls

Question 30

What is coronary bypass surgery?

Answer 30

Creating a new passage for blood flow to cardiac muscle by bypassing a blocked area

Question 31

What are the characteristics of arteries?

Answer 31

* Carry blood at high pressure * Carry oxygenated blood (except pulmonary artery) * Thick muscular walls * Narrow lumen * Fast flow speed

Question 32

What are the characteristics of veins?

Answer 32

* Carry blood at low pressure * Carry deoxygenated blood (except pulmonary vein) * Thin walls * Large lumen * Contain valves * Slow flow speed

Question 33

What are the characteristics of capillaries?

Answer 33

* Carry blood at low pressure * Carry both oxygenated and deoxygenated blood * One cell thick walls * Leaky walls * Slow flow speed

Question 34

What is the function of the coronary arteries?

Answer 34

Supply blood to the heart muscle

Question 35

What are red blood cells?

Answer 35

Biconcave discs containing no nucleus but plenty of hemoglobin

Question 36

What are white blood cells?

Answer 36

Large cells containing a big nucleus with different types having varied structures and functions

Question 37

What are platelets?

Answer 37

Fragments of cells involved in blood clotting

Question 38

What is plasma?

Answer 38

Straw-colored liquid that carries blood cells and nutrients

Question 39

What is phagocytosis?

Answer 39

The process by which phagocytes engulf pathogenic cells and digest them.

Question 40

What triggers phagocytes to detect pathogenic cells?

Answer 40

Chemicals produced by pathogenic cells.

Question 41

What do phagocytes release to digest engulfed pathogens?

Answer 41

Digestive enzymes.

Question 42

How can phagocytes be recognized under a microscope?

Answer 42

By their multi-lobed nucleus and granular cytoplasm.

Question 43

What is the primary function of lymphocytes?

Answer 43

To produce antibodies and antitoxins.

Question 44

What do antibodies do?

Answer 44

Destroy pathogenic cells.

Question 45

What is the role of antitoxins produced by lymphocytes?

Answer 45

Neutralize toxins released by pathogens.

Question 46

How can lymphocytes be identified under a microscope?

Answer 46

By their large round nucleus and clear, non-granular cytoplasm.

Question 47

Fill in the blank: Phagocytes have a sensitive cell surface membrane that can detect _______ produced by pathogenic cells.

Answer 47

chemicals

Question 48

True or False: Lymphocytes have a multi-lobed nucleus.

Answer 48

False