Unit 3 - The Heart

Question 1

What do arteries do?

Answer 1

They carry blood away from the heart, at high pressure

Question 2

What sort of blood do arteries carry?

Answer 2

Oxygenated

Question 3

Name the layers that arteries have (3)

Answer 3

• Thin tough outer layer
• Thick muscular middle layer
• Thick inner layer of cells

Question 4

Arteries: size of the lumen?

Answer 4

Small

Question 5

Arteries: Pulse?

Answer 5

Yes

Question 6

Arteries: Valves?

Answer 6

No

Question 7

What do Veins do?

Answer 7

Carry deoxygenated blood toward the heart at low pressure

Question 8

The 3 layers than veins have?

Answer 8

• Thick tough outer layer
• Muscular middle layer
• Thin inner layer of cells

Question 9

Veins: size of the lumen?

Answer 9

Large

Question 10

Veins: Pulse?

Answer 10

They do not have a pulse

Question 11

Veins: Valves?

Answer 11

Yes, to prevent backflow of blood

Question 12

Capillaries: join what to what?

Answer 12

Arteries to veins

Question 13

Capillaries: branched from what?

Answer 13

Arteries (Arteries branch into capillaries)

Question 14

Capillaries: walls?

Answer 14

1 cell thick

Permeable (so substances can diffuse in and out)

Carry blood close to every cell to exchange substances with them

Question 15

Name the 4 chambers?

Answer 15

• Right atrium
• Right ventricle
• Left atrium
• Left ventricle

Question 16

What is the Vena carva?

Answer 16

The vein which brings deoxygenated blood from ther body

Question 17

What does the tricuspid do?

Answer 17

Lets blood flow in 1 direction from the right atrium to the right ventricle

Question 18

What does the pulmanory artery do?

Answer 18

Takes the deoxygenated blood from the right ventricle to the lungs

Question 19

What does the pulmonary vein do?

Answer 19

Brings blood from the lungs to the left atrium

Question 20

What does the bicuspid valve do?

Answer 20

Lets blood flow in 1 direction from the left atrium to the left ventricle

Question 21

What does the Aorta do?

Answer 21

Carries oxygenated blood to the body from the left ventricle

Question 22

Why does the LV contain a much larger muscle wall?

Answer 22

Because it is used to create more pressure as blood from the LV must travel around the body which is further than the R as it is going to the lungs

Question 23

Describe the flow of blood through the heart in order

Answer 23

1. Blood flows into the left and right atriums from the vena carva to the pumlmonary vein
2. The atriums contract, forcing the blood into the pulmonary artery and the aorta and out of the heart
3. The blood then flows to the organs through arteries and returns through the veins
4. The L and R atriums fill again and the whole cycle starts again

Question 24

What do pacemakers do?

Answer 24

Send impulses to the heart muscle, making it contact

Question 25

How do arteries become blocked?

Answer 25

By age, saturated fat, tobacco smoke which cause fatty deposits to build up in artery walls

Question 26

What are stents used for?

Answer 26

To open blocked arteries to increase blood flow ![]()

Question 27

What are the disadvantages of heart transplants?

Answer 27

* It is a **traumatic operation**, recipient must take drugs to supress the immune system and prevent rejection (which isn't the case with pacemakers/valve transplants) * There is a shortage of donors * The opeation carries risk of infection * Long waiting time