The Heart and Diffusion

Question 1

What is plasma in the blood?

Answer 1

Clear, yellowy liquid which transports blood cells, proteins and dissolved substances around the body.

Question 2

What is the pigment found in red blood cells used to bind to oxygen?

Answer 2

Haemoglobin.

Question 3

What is the function of red blood cells?

Answer 3

To transport oxygen around the body.

Question 4

What is the blood vessel type which is used to transport blood from the heart to other sides of the body?

Answer 4

Artery.

Question 5

What are the lower chambers of the heart called?

Answer 5

Ventricles.

Question 6

How does a blood cell’s biconcave structure help it with it’s function?

Answer 6

Increases the SA:V ratio to make diffusion more efficient.

Question 7

What is the blood vessel type which links arteries and veins?

Answer 7

Capillary.

Question 8

In a respiration experiment, why does carbon dioxide not collect in the test tube?

Answer 8

It is absorbed by the soda lime.

Question 9

What are the upper chambers of the heart?

Answer 9

Atria.

Question 10

State 4 adaptations of an Erythrocyte.

Answer 10

-Biconcave structure to increase SA:V ratio for better diffusion rates
-Contains haemoglobin to allow oxygen to bind to the cell
-No nucleus to carry more oxygen.
-Small and Flexible to fit into narrow blood vessels.

Question 11

Why is the muscle wall of the left ventricle thicker than that of the right ventricle?

Answer 11

Because the left ventricle requires more strength to pump blood from the heart around the body, unlike the right ventricle, which only needs to pump blood to the lungs from the heart.

Question 12

Why does the heart have valves?

Answer 12

To prevent backflow of blood and to ensure it flows in the correct direction.

Question 13

How does deoxygenated blood enter the heart?

Answer 13

Through the vena cava into the right atrium.

Question 14

How does oxygenated blood enter the heart?

Answer 14

Through the pulmonary vein into the left atrium.

Question 15

Which sides of the heart deal with which types of blood?

Answer 15

The left side deals with oxygenated blood, the right deals with oxygenated blood.

Question 16

Why do the atria and ventricles contract at different times?

Answer 16

To ensure the ventricles are filled with blood before they pump it out the heart.

Question 17

What is the blood vessel which delivers oxygenated blood to the rest of the body from the heart?

Answer 17

Aorta

Question 18

State 3 adaptations of the artery.

Answer 18

-Thick, elastic muscular wall to withstand high pressure.
-High blood pressure to deliver oxygenated blood faster.
-Ability to regulate blood flow by constricting and dilating muscle walls.

Question 19

State 3 adaptations of the vein.

Answer 19

-Large lumen to deliver more deoxygenated blood at a time.
-Valves to prevent backflow.
-Flexible muscle walls to fit varying volumes of blood at once.

Question 20

State 3 adaptations of the capillary.

Answer 20

-Permeable walls to allow diffusion in and out.
-1 cell wide lumen to ensure all red blood cells diffuse substances through.
-1 cell thick walls to allow for faster diffusion.

Question 21

What is the formula for diffusion rate?

Answer 21

(surface area x difference in concentration gradient) / thickness of surface