Circulation

Question 1

Adaptations of Red Blood Cells

Answer 1

Transports oxygen with biconcave disc shape for large surface area to volume ratio
no nucleus for room for haemoglobin which binds to oxygen to form oxyhaemoglobin

Question 2

What side of the heart does oxygenated blood enter?

Answer 2

Left side

Question 3

What side of the heart does deoxygenated blood enter?

Answer 3

Right side

Question 4

Which blood vessel pumps blood towards the heart?

Answer 4

VeIN. IN to the heart

Question 5

Which blood vessel pumps blood away from the heart?

Answer 5

Artery. Away from the heart.

Question 6

What are the purpose of valves?

Answer 6

To prevent backflow of blood that is travelling at a low pressure.

Question 7

Describe the structure of veins

Answer 7

Thin outer wall, thin elastic and muscle tissue.
Blood travels at low pressure.
Contains valves (semi-lunar) to prevent backflow of blood.
Large lumen.
Usually carries deoxygenated blood into the heart.

Question 8

Which ventricle wall is thicker and why?

Answer 8

Left because it needs to pump the blood around the body at a higher pressure and it needs to pump the blood further around the body.

Question 9

What does the right side of the heart do?

Answer 9

Pumps deoxygenated blood to the lungs

Question 10

What does the left side of the heart do?

Answer 10

Pumps oxygenated blood to the body.

Question 11

What is the left and right side of the heart separated by?

Answer 11

The septum.

Question 12

What is the function of the circulatory system?

Answer 12

To transport substances around the body.

Question 13

Name of valve between right atrium and right ventricle

Answer 13

Tricuspid valve

Question 14

Name of valve between left atrium and left ventricle

Answer 14

Bicuspid valve

Question 15

Name of valve between right ventricle and pulmonary artery

Answer 15

Semi-lunar valve

Question 16

Name of valve between left ventricle and aorta

Answer 16

Semi-lunar valve

Question 17

What are the names of the artery(s) and vein(s) involving the liver?

Answer 17

Hepatic vein, hepatic artery and hepatic portal vein (leads to stomach and intestines)

Question 18

What are the names of the artery(s) and vein(s) involving the kidneys?

Answer 18

Renal vein and renal artery

Question 19

Generally, what type of blood do veins carry and what is the exception?

Answer 19

Deoxygenated blood (they are blue) except the pulmonary vein which carries oxygenated blood from the lungs to the heart.

Question 20

Generally what type of blood do arteries carry and what is the exception?

Answer 20

Oxygenated blood (they are red) except the pulmonary artery which carries deoxygenated blood from the heart to the lungs.

Question 21

What are phagocytes?

Answer 21

Larger cells with a multi-lobed nucleus that engulf and digest pathogens. A type of white blood cell.

Question 22

What are lymphocytes

Answer 22

Cells with a very large nucleus that make and release antibodies, which bind to and destroy pathogens.

Question 23

What are platelets?

Answer 23

Cell fragments that help clot blood and form scabs.

Question 24

What is plasma?

Answer 24

Straw coloured liquids that transports blood cells and many other substances including:
dissolved nutrients (glucose, amino acids…) dissolved waste products (CO2 and Urea) and hormones, heat energy and proteins.

Question 25

What are red blood cells?

Answer 25

Small red cells that carry oxygen around the body and contain haemoglobin (oxygen binds to hameoglobin).

Question 26

How are red blood cells specialised for their job?

Answer 26

No nucleus - more room for haemoglobin so more oxygen can be transported.
Biconcave disc - increases SA:V and decreases distance. Increases diffusion.
Contain haemoglobin - a protein that combines with oxygen to form oxyhaemoglobin. Transports oxygen to respiring cells.

Question 27

Describe the structure of arteries

Answer 27

Thick outer wall
Thick layer of muscle and elastic tissue
Blood flows at a high pressure
Small lumen
Usually carries oxygenated blood away from heart.

Question 28

Describe the structure of capillaries

Answer 28

Walls are once cell thick.

Question 29

How does the structure of a vein link to its function?

Answer 29

Valves prevent blood flowing backwards.
Blood travels at a low pressure so thick walls aren’t needed.
Layer of muscle and elastic tissue means that wall can contract to keep blood flowing.

Question 30

How does the structure of an artery link to its function?

Answer 30

Thick outer wall means it can transport blood at a high pressure without bursting.
Thick layer of elastic tissue allows artery to stretch and recoil to keep blood flowing at a high pressure.
Thick layer of muscular tissues means helps to control flow of blood by dilatating and constricting.
Small lumen and thick outer wall means that blood travels at a high pressure to travel all around the body.

Question 31

How does the structure of a capillary link to its function?

Answer 31

Wall is one cell thick so short distance for diffusion of substances from blood into tissues.

Question 32

Factors that increase the risk of coronary heart disease

Answer 32

Obesity - increases blood pressure
Smoking - increases blood pressure and risk of fatty deposits forming
High blood pressure - increases risk of fatty deposits forming and damages artery lining
Lack of exercise - High blood pressure
Diet - High consumption of saturated fats leads to fatty deposits as it increases cholesterol.