Circulatory system in humans

Question 1

What is the structure of the red blood cell?

Answer 1

Small

Biconcave disc shape - increases surface
area so there is more membrane for oxygen to diffuse through

No nucleus

Regular shaped

Cell membrane contains haemoglobin for transport of oxygen

Look at page 4 in your booklet for reference

Question 2

What is the aorta?

Answer 2

Major blood vessel which carries oxygenated blood from the heart to the body

Question 3

What do arteries do?

Answer 3

They carry blood away from the heart

Question 4

What are capillaries?

Answer 4

Smallest and thinnest blood vessels

Question 5

What is cardiovascular disease?

Answer 5

Disease of the heart and circulatory system

Question 6

What are coronary arteries?

Answer 6

Blood vessels on the surface of the heart that supply the muscle with blood

Question 7

What is deoxygenated blood?

Answer 7

Blood that had most of its oxygen removed

Question 8

What is meant by a double circulation?

Answer 8

Heart separated into two sides. Half goes to the body and other half goes to the head. It separates oxygen to deoxygenate and oxygenate .

Question 9

What is haemoglobin?

Answer 9

Carry’s oxygen and gives red blood cells its colour

Question 10

What is a pathogen?

Answer 10

A disease-causing organism

Question 11

The function of the heart? And what is it made out of?

Answer 11

1. Pump blood to parts of the body

2. It’s made out of muscle/cardiac muscle

Question 12

What is a phagocyte?

Answer 12

Type of white blood cell that engulf and destroy bacteria

Question 13

What is plasma?

Answer 13

The liquid part of blood

Also it carries
carbon dioxide
Soluble nutrients
Hormones
Urea

And it also distributes heat

Question 14

Which blood vessel in the heart takes blood to the heart muscle cells to supply them with oxygen and glucose for respiration?

Answer 14

Coronary arteries

Question 15

What is a platelet?

Answer 15

Cell fragments that help the blood to clot

Question 16

What is the pulmonary artery?

Answer 16

Artery that transports deoxygenated blood, from the right ventricle, to the lungs

Question 17

What is the pulmonary vein?

Answer 17

Vein which returns oxygenated blood from the lungs to the left atrium

Question 18

Starting from the vena cava, list the vessels, chambers, valves and organs that blood passes through until you reach lungs.

Answer 18

Vena cava > right atrium > tricuspid valve > right ventricle > semi-lunar valve > pulmonary artery > to lungs.

Question 19

What is the function of the valves in the heart?

Answer 19

Ensure one-way flow of the blood

Question 20

Why does the left ventricle have the thickest muscular wall?

Answer 20

To pump the blood further around the body with that high pressure

Question 21

Which chamber has the thinnest wall and why?

Answer 21

Right atrium as it only pumps blood for the next chamber

Question 22

What does the vein do?

Answer 22

Carry blood into the heart

Question 23

What is the structure of the artery?

Answer 23

1. Thick muscular inner and outer walls
2. Smaller lumen
3. Elastic

Question 24

What is the structure of the capillaries?

Answer 24

One cell thick

Question 25

What is one way that reduces risk of heart disease?

Answer 25

Statins as it lowers level of blood cholesterol

Question 26

What is the structure of the veins?

Answer 26

1. Thinner inner and outer walls 2. Larger lumen 3. Contains valves

Question 27

What do valves do?

Answer 27

Prevent backflow of blood

Question 28

What is the vena cava?

Answer 28

Major blood vessel which returns deoxygenated blood from the body to the heart

Question 29

What are 3 lifestyle changes that may reduce the risk of cardiovascular disease (CVD)?

Answer 29

1. Regular exercise 2. Less saturated fat + salt in diet 3. Stop smoking

Question 30

What lifestyle factors may greatly increase the risk of a person suffering from cardiovascular disease (CVD)?

Answer 30

1. High salt diet = high blood pressure 2. Smoking = carbon monoxide limiting how much O2 (oxygen) can be carried 3. High fat diet = high blood cholesterol 4. Lack of exercise 5. Being overweight/obese = fat stored around heart meaning the heart may have to work harder

Question 31

Structure of phagocyte? (type of white blood cell)

Answer 31

Has a flexible membrane (so the shape of the border is wavey and weird) Has a lobed nucleus (so the shape of nucleus is weird) Contains cytoplasm Look at bottom of page 4 in ur book for reference

Question 32

Explain how a diet in high saturated fat + salt can cause a person to have a heart attack, a stroke.

Answer 32

High saturated fat diet = increase in blood cholesterol levels and high blood pressure High cholesterol = cause formation of plaques in walls of coronary arteries meaning less blood can flow through narrowed arteries Heart muscle cells don't receive enough oxygen = heart stops contracting causing heart attack High blood pressure = cause burst in blood vessel in brain = stroke

Question 33

How do phagocytes engulf other cells? (Particularly bacteria)

Answer 33

They use "cytoplasm arms" aka "pseudopods" to surround the bacteria , trap it, and completely engulf it Bacteria trapped inside the phagosome are broken down by enzymes (RIP in peace) Look in page 5 of ur booklet for reference

Question 34

Starting from the lungs, list the vessels, chambers, valves and organs that blood passes through until you reach the vena cava.

Answer 34

from lungs > pulmonary vein > left atrium > bicuspid valve > left ventricle > semi-lunar valve > aorta > to body > from body > vena cava.