The Heart and Circulatory Sytem

Question 1

Why do large organisms need a transport system?

Answer 1

To move materials around the body.

Question 2

What does the human circulatory system consist of?

Answer 2

The human circulatory system consists of: blood vessels, the heart and blood.

Question 3

What is the heart?

Answer 3

The heart is a muscular organ consisting of two pumps held together that pump blood around the body.

Question 4

What does the right pump of the heart do?

Answer 4

The right pump forces deoxygenated blood to the lungs where it picks up oxygen and loses carbon dioxide.

Question 5

What happens to oxygenated blood when it returns to the heart?

Answer 5

After returning to the heart, oxygenated blood is then pumped to the rest of the body by the left pump.

Question 6

What are the four chambers of the heart?

Answer 6

The left and right atria

The left and right ventricle

Question 7

Where does the left atrium receive blood from?

Answer 7

The Pulmonary vein

Question 8

Where does the right atrium receive blood from?

Answer 8

The Vena cava

Question 9

What do the atria do to move blood into the ventricles?

What happens when the ventricles contract?

Answer 9

The atria contract to move blood into the ventricles. When the ventricles contract they move blood into the pulmonary artery from the right side and into the aorta on the left side.

Question 10

What is the role of valves in the heart?

The heart is supplied with oxygenated blood via which artery?

Answer 10

Valves in the heart prevent blood from flowing in the wrong direction.
The heart is supplied with oxygenated blood via the coronary arteries.

Question 11

What does the action of the two sides of the heart result in?

Answer 11

The action of the two sides of the heart results in double circulation.

Question 12

What are the three main types of blood vessel and what are their features?

Answer 12

Arteries:
1) Carry blood away from the heart
2) Have thick walls containing muscle and elastic tissue
Veins:
1) Have thinner walls than arteries
2) Often have valves along their length to prevent backflow of blood.
Capillaries:
1) Are narrow, thin-walled vessels
2) carry the blood through organs and allow the exchange of substances with all the living cells in the body.

Question 13

What happens if blood vessels are blocked or too narrow?

Answer 13

If blood vessels are blocked or too narrow, blood will not flow through them efficiently and the organs will be deprived of nutrients and oxygen.

Question 14

What are stents used for?

Answer 14

Stents can be inserted yo keep blood vessels open, this is particularly beneficial when coronary arteries become narrowed due to fatty deposits cutting off the blood supply to the heart.

Question 15

What is the problem with leaky valves?

What can be done to solve the problem?

Answer 15

Leaky valves mean the blood could flow in the wrong direction, artificial or animal valves can be inserted in the heart to replace damaged valves.

Question 16

What is blood?

What does plasma contain?

Answer 16

Blood is a tissue.

The fluid plasma contains red blood cells, white blood cells and platelets.

Question 17

What three substances does blood plasma transport?

Answer 17

Blood plasma transports:

1) Carbon dioxide from the organs to the lungs
2) Soluble products of digestion from the small intestine to other organs
3) Urea from the liver to the kidneys where urine is made.

Question 18

Give four properties of red blood cells.

Answer 18

Red blood cells:

1) Are biconcave discs which do not have a nucleus
2) Contain the red pigment haemoglobin
3) Use their haemoglobin which combines with oxygen to form oxyhemoglobin in the lungs.
4) Carry the oxygen to all the organs where the oxyhemoglobin splits into haemoglobin and oxygen.

Question 19

Give two properties of white blood cells?

Answer 19

White blood cells:

1) Have a nucleus
2) Form part of the body’s defence system against microorganisms

Question 20

Give three properties of platelets.

Answer 20

Platelets:

1) Are small fragments of cells
2) Do not have a nucleus
3) Help to clot at the site of a wound

Question 21

Equation for reversible reaction of oxygen and haemoglobin.

Answer 21

Oxygen + Haemoglobin Oxyhaemoglobin

Question 22

How can blood from blood donors be separated?

What must be done to donated blood?

Answer 22

Blood from blood donors can be separated into cells and plasma.
Donated blood must be refrigerated, some can be frozen.

Question 23

How can donated blood plasma be given to patients and what does this do?

Answer 23

The Plasma can be given to patients in a transfusion to increase blood volume.

Question 24

Name one type of artificial blood and give two benefits of this.
Give four negatives of artificial blood.

Answer 24

Perfluorocarbons, PFC’s are a type of artificial blood which does not need to be refrigerated, it does not contain cells, so blood matching is not necessary.
Negatives:
1) Artificial blood is expensive
2) It does not carry as much oxygen as whole blood.
3) Some types are insoluble in water so do not mix well with blood.
4) Some types cause unpleasant side effects.

Question 25

What may patients who suffer from heart failure need?

What are being developed due to a lack of heart donors?

Answer 25

Patients who suffer from heart failure may need a new heart.

There is a lack of heart donors so artificial hearts are being developed to keep the patients alive.

Question 26

Give two advantages and three disadvantages of artificial hearts.

Answer 26

Advantages:
1) Tissue matching is not required
2) No need for immunosuppressant drugs
Disadvantages:
1) Problems with blood clotting
2) Requires long stays in hospital
3) Expensive

Question 27

What does xylem tissue transport?

Answer 27

Xylem tissue transports water and mineral ions from the roots to the stem, leaves and flowers.

Question 28

What is the transpiration stream?

Answer 28

The transpiration stream is the movement of water and mineral ions from the roots and out of leaves.

Question 29

What does phloem tissue transport?

Answer 29

Phloem tissue transports dissolved sugars from the leaves to the rest of the plant, including the growing regions and the storage organs.