B5 The Circulatory System

Question 1

What is the job of the circulatory system?

Answer 1

To move substances around effectively in humans

Question 2

Why is the circulatory system made up of?

Answer 2

Heart
Blood vessels
Blood

Question 3

Complete the sentence

Humans and other mammals have a ……. circulatory system

Answer 3

Double

Two circuits joined together

Question 4

What do each of the circulatory systems do?

Answer 4

In the first one:
The heart pumps deoxygenated blood to the alveoli in the lungs to take in oxygen. Oxygenated blood then returns to the heart.

In the second one:
The heart pumps oxygenated blood around all the other organs of the body. Here the blood gives up its oxygen at the blood cells. The deoxygenated blood then returns to the heart to be pumped out to the lungs again.

Question 5

See p 69 for a diagram of the circulatory system

Answer 5

.

Question 6

Complete the sentence

As it is pumped around the body, the blood also travels through …….. near exchange surfaces

Answer 6

Blood vessels

Question 7

Name two areas where the blood travels through blood vessels near exchange surfaces

Answer 7

Villi (where it picks up food molecules and water)

Kidneys (where it is filtered and urea is removed)

Question 8

What is the hearts role?

Answer 8

To pump blood around the body

Question 9

Name the four chambers of the heart

Answer 9

Left atrium
Right atrium
Left ventricle
Right ventricle

Question 10

What does the heart use it’s four chambers for?

Answer 10

To pump blood around.

Question 11

What does the heart have to make sure the blood flows in the right direction?

Answer 11

Valves

Question 12

What happens to the atria when the ventricles contract?

Answer 12

The valves to the atria close and the valves to the blood vessels open.

Question 13

What do the valves in the heart prevent?

Answer 13

Backflow (when blood flows backwards)

Question 14

What is the difference between atria and atrium?

Answer 14

Atria is plural, atrium is when there is just one.

Question 15

See p 69for a diagram of the internal and external structure of the heart

Answer 15

.

Question 16

Complete the sentence

Blood flows into the two atria from the …….. and the …….

Answer 16

Vena cava

Pulmonary vein

Question 17

Complete the sentence

The atria ………, pushing the blood into the ……….

Answer 17

Contract

Ventricles

Question 18

Complete the sentence

The ventricles contract, forcing the blood into the ………. and the ……, and out of the heart

Answer 18

Pulmonary artery

Aorta

Question 19

Complete the sentence

The blood flows to the organs, including the lungs, through ……….
And returns through ……..

Answer 19

Arteries

Veins

Question 20

List the 5 stages of the heart pumping blood around the body

Answer 20

1. Blood flows into atria from vena cava and the pulmonary vein.
2. The atria contract, pushing the blood into the ventricles.
3. The ventricles contract, forcing the blood into the pulmonary artery and the aorta, and out of the heart.
4. The blood then flows to the organs, including the lungs, through arteries and returns through veins.
5. The atria fill again and the whole cycle starts over.

Question 21

What is the heart made up of?

Answer 21

Cardiac muscle

Question 22

Complete the sentence

Cardiac muscle contains loads of ………. to provide them with ATP

Answer 22

Mitochondria

Question 23

Why do cardiac muscles contain loads of mitochondria?

Answer 23

To provide them with ATP.

This release energy needed for the muscle to contract

Question 24

Complete the sentence

Blood is supplied to the cardiac muscle by two …………, which branch from the base of the ………

Answer 24

Coronary arteries

Aorta

Question 25

What do the coronary arteries do?

Answer 25

Allow the oxygen and glucose needed for the hearts cells to respire to diffuse through the thick walls of the heart.

Question 26

Which chamber of the hearts pumps deoxygenated blood to the lungs? (1mark)

Answer 26

The right ventricle