B2 Circulatory System - The Heart (page 31)

Question 1

What is the Circulatory system for?

Answer 1

it carries food and oxygen to every cell in the body.

(as well as being a delivery service, it’s also a waste collection service - it carries waste products to where they can be removed from the body).

Question 2

What is the Circulatory system made up of?

Answer 2

the heart, blood vessels and blood.

Question 3

Do humans have a double circulatory system and are they joined?

Answer 3

yes, it has two circuits joined together.

Question 4

in the first ‘double circulatory system’, the RIGHT ventricle does what?

Answer 4

it pumps deoxygenated blood (blood without oxygen) to the lungs to take in oxygen. The blood then returns to the heart.

Question 5

in the second ‘double circulatory system’, the LEFT ventricle does what?

Answer 5

it pumps oxygenated blood around all the other organs of the body. The blood gives up its oxygen at the body cells and the deoxygenated blood returns to the heart to be pumped out to the lungs again.

(see diagram on page 31).

Question 6

The Heart contracts, what do this mean?

Answer 6

it pumps blood around the body.

Question 7

What is the Heart, and what do it do?

Answer 7

The heart is a pumping organ that keeps the blood flowing around the body.

Question 8

What are the walls of the heart mostly made of?

Answer 8

muscle tissue.

Question 9

Do the heart have valves, explain your answer?

Answer 9

yes they have valves to make sure that blood flows in the right direction - they prevent it flowing backwards.

Question 10

How do the heart keep the blood flowing in the right direction?

Answer 10

it has four chambers, which keeps the blood to pump around in the right direction.

right atrium, right ventricle
left atrium and left ventricle.

Question 11

Explain the process of how the blood pumps around the heart?

Answer 11

1) Blood flows into the two atria from the 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 through arteries, and returns through veins

5) The atria fill again and the whole cycle starts over.

Question 12

The heart also needs its own supply of oxygenated blood, what is the process for this?

Answer 12

Arteries called coronary arteries branch off the aorta and surround the heart, making sure that it gets all the oxgenated blood it needs.

(please look at diagram on page 31 of the heart and valves, as you may need to label them in your exam).

Question 13

What do Atrium and Atria mean?

Answer 13

Atrium is when there is just one.

Atria is plural (more than one)

Question 14

How is your resting heart rate controlled?

Answer 14

by a group of cells in the right atrium wall that act as a pacemaker

Question 15

explain what a pacemaker in the heart is?

Answer 15

The cells produce a small electrical impulse which spreads to the surrounding muscle cells, causing them to contract.

Question 16

Why would an ‘artificial pacemaker be used?

Answer 16

artificial pacemaker is often used to control the heartbeat if the natural pacemaker cells don’t work properely. (e.g. if the patient has an irregular heartbeat). It’s a little device that’s implanted under the skin and has a wire going to the heart. It produces an electric current to keep the heart beating regularly).

Question 17

When doctors use a stethoscope, what are they listening for?

Answer 17

they listen to your heart, it’s the valves closing they can hear.

Question 18

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

Answer 18

The right ventricle (1 mark)

Question 19

What is the function of the coronary arteries? (1 mark)

Answer 19

They supply oxygenated blood to the heart itself (1 mark)