Chapter 4: Organising Plants and Animals

Question 1

What do plasma carry?

Answer 1

red blood cell, white blood cells, platelets

Question 2

What are red blood cells?

Answer 2

biconcave cells that contain the red pigment hemoglobin and carry oxygen around the body and blood.

Question 3

What are white blood cells?

Answer 3

blood cells involved in the immune system of the body. They engulf pathogens and make antibodies and antitoxins

Question 4

What are platelets?

Answer 4

fragments of cells in the blood that play a vital role in the clotting mechanism of the blood

Question 5

White bloods cells help protect against _______.

Answer 5

infections

Question 6

What are the 3 main types of blood vessels?

Answer 6

1. arteries
2. veins
3. capillaries

Question 7

What are arteries?

Answer 7

arteries are blood vessels that carry blood away from the heart. They usually carry oxygenated blood and have a pulse

Question 8

What are veins?

Answer 8

blood vessels that carry blood to the heart. They usually carry deoxygenated blood and have valves to prevent backflow of blood.

Question 9

What are capillaries?

Answer 9

the smallest blood vessels. They run between individual cells and have a wall that is only one cell thick.

Question 10

Which blood vessel has the thickest layer of muscle, thick walls, and a small lumen?

Answer 10

artery

Question 11

Which blood vessel has a large lumen, thin walls, and often have valves?

Answer 11

vein

Question 12

What is a double circulatory system?

Answer 12

the circulation of blood from the heart to the lungs is separate from the circulation of blood from the heart to the rest of the body

Question 13

What are coronary arteries?

Answer 13

the blood vessels that supply oxygenated blood to the heart muscle

Question 14

How many chambers does the heart have?

Answer 14

4

Question 15

do ventricles pump blood into the heart, or out of the heart?

Answer 15

out

Question 16

How does blood pass through the heart?

Answer 16

• ventricles contract and force blood out of the heart
• the right ventricle forces deoxygenated blood to the lungs in the pulmonary artery
• the left ventricle pumps oxygenated blood around the body in the aorta

Question 17

What is coronary heart disease?

Answer 17

This is when the arteries that supply blood to the blood muscle become narrow.

Question 18

What is the issue with coronary heart disease?

Answer 18

If the blood flow through the coronary arteries is reduced, then the supply of oxygen to the heart is reduced.

Question 19

How can coronary heart disease be solved?

Answer 19

This issue can be solved with a stent

Question 20

What is a stent?

Answer 20

A stent is a metal mesh that is placed in the artery

Question 21

How do stents work?

Answer 21

A tiny balloon is inflated to open up the blood vessel and the stent at the same time. The balloon is deflated and removed but the stent stays in place, holding the blood vessel open.

Question 22

What is an alternative to stents?

Answer 22

Doctors can carry out bypass surgery, replacing narrow or blocked coronary arteries with bits of veins from other parts of the body

Question 23

How can damaged heart valves be replaced?

Answer 23

they can be replaced by using biological or mechanical valves

Question 24

What is a natural pacemaker?

Answer 24

The resting heart rate is controlled by a group of cells in the right atrium that form a natural pacemaker

Question 25

What is an artificial pacemaker?

Answer 25

artificial pacemakers are electrical devices used to correct irregularities in the heart rhythm.

Question 26

Why are artificial hearts used?

Answer 26

to keep patients alive while they wait for a transplant, or for their heart to rest as an aid to recovery

Question 27

What is the job of your ventilation system?

Answer 27

To move air in and out of our lungs, which provide an efficient surface for gas exchange in the alveoli

Question 28

What makes gas exchange in the alveoli quick and effective?

Answer 28

The alveoli provide a very large surface area and a rich supply of blood capillaries. This means that gases can diffuse into and out of the blood as efficiently as possible