Circulatory System

Question 1

What is the function of the circulatory system?

Answer 1

To transport substances around the body.

Question 2

What are the three main components of the circulatory system?

Answer 2

1. Blood
2. Heart
3. Blood vessels (veins, arteries and capillaries).

Question 3

What is blood made up of?

Answer 3

1. Plasma
2. Red Blood Cells
3. White Blood Cells
4. Platelets

Question 4

What is the job of red blood cells?

Answer 4

To pick up oxygen in the lungs and transport it to other cells of the body, then transport carbon dioxide from the cells back to the lungs for removal.

Question 5

What is the job of white blood cells?

Answer 5

To work with the immune system, and look for and destroy foreign bodies.

Question 6

What is plasma and what is its role?

Answer 6

1. Its a liquid made up mainly of water and dissolved substances (eg. glucose).
2. Its role is to absorb the nutrients from the digestive system for transport around the body.

Question 7

What is the job of platelets?

Answer 7

They are cell fragments that form clots when you have a wound.

Question 8

What are the 3 types of blood vessels?

Answer 8

1. Arteries
2. Veins
3. Capillaries
   They have different adaptations (size and structure) based on what volume and speed of blood they have to carry.

Question 9

What is the role and adaptations of arteries?

Answer 9

To carry blood away from the heart. They have thick, muscular walls to cope with high pressure (just been pumped from the heart) and to help move blood along.

Question 10

What is the role and adaptations of veins?

Answer 10

To carry blood back to the heart. They have a small amount of muscle in their walls because the blood is low pressure. To avoid any blood going backwards due to a lack of pressure, veins have one-way valves in them.

Question 11

What is the role and adaptations of capillaries?

Answer 11

To connect arteries and veins. They have thin walls (1 cell thick) to allow maximum diffusion of substances in and out of blood.

Question 12

What is the function of the heart and how many chambers does it have?

Answer 12

• To pump blood around the body.
• It has 4 chambers (2 receiving chambers (atria), and 2 pumping chambers (ventricles)).

Question 13

Which side of the heart receives the oxygenated blood?

Answer 13

Left. It then gets pumped through the body. The right receives deoxygenated blood which it pumps to the lungs.

Question 14

What happens once the blood has been oxygenated by the alveoli (flow of the blood)?

Answer 14

1. The oxygen rich blood flows from the capillaries around the alveoli and to the left side of the heart. It exits through the pulmonary vein.
2. The blood then goes to the left ventricle.
3. The blood exits through the aorta and out into the body down the left side of the body.
4. This blood makes its way to the capillaries where the oxygen is delivered to where it needs to be through diffusion. This is cellular respiration using the concentration gradient.
5. Carbon dioxide is also diffused into the blood and is transported back to the heart via the venules and then the veins. Blood coming from below the heart enters via the inferior vena cava. Deoxygenated blood from above the heart enters the heart via the superior vena cava.