The Circulatory System Flashcards Preview

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Flashcards in The Circulatory System Deck (30):
0

Why do we have a double circulatory system?

One pumps deoxygenated blood to the lungs to take in oxygen and the other pumps oxygenated blood around the body to give up its oxygen to the body cells

1

How does the heart pump blood around the body?

It's contracts

2

How many chambers does the heart have?

4

3

Name the 4 chambers of the heart

Right atrium, right ventricle, left atrium and left ventricle

4

Where does the blood which flows into the atriums come from?

The vena cava or the pulmonary vein

5

When the atriums contract, where does the blood go?

Into the ventricles

6

When the ventricles contract, where does the blood go?

The pulmonary vein or the aorta and out of the heart

7

What does the blood flow to the organs through?

Arteries

8

What does the blood flow through when it returns to the heart?

Veins

9

How many types of blood vessels are there?

3

10

What is the function of an artery?

To carry blood away from the heart

11

What is the function of a capillary?

They're involved in the exchange of materials at the tissues

12

What is the function of a vein?

To carry blood to the heart

13

How is an artery adapted?

The walls are strong and elastic to withstand pressure and they have layers of muscles to keeps them strong with elastic fibres to allow them to stretch and spring back

14

How is a capillary adapted?

They're really small so they can get to every cell, they have permeable walls do diffusion can happen and they are only one cells thick so this increases the rate of diffusion

15

How is a vein adapted?

Less thick walls because not as much pressure and valves to help keep the blood flow in the right direction

16

What are the 4 main things in the blood?

Red blood cells, white blood cells, platelets and plasma

17

What do red blood cells do and why are the good at this?

The carry oxygen - they have a doughnut shape giving them a large surface area for absorbing more oxygen, they don't have a nuclear do more space for oxygen and they carry haemoglobin

18

What is haemoglobin?

A red pigment which combines with oxygen in the lungs to make oxyhemoglobin and in body tissues the oxyhemoglobin splits up into haemoglobin and oxygen into release oxygen into the cells

19

What do white blood cells do and why are the good at this?

Defend against disease - they change shape to engulf microorganism and produce antibodies and antitoxins

20

What do platelets do and why are the good at this?

Help blood clot - they are small fragments of cells which help the blood to clot at wounds

21

What does plasma do and why are they good at this?

Carries everything in the blood - carries red and white blood cells, platelets, nutrients, carbon dioxide, urea, hormones, antitoxins and antibodies

22

What is coronary heart disease?

A disease where the arteries that supply blood to your heart get blocked by fatty deposits which makes the arteries narrow and restricts blood flow which can result in a heart attack

23

What can you do to resolve this?

Insert stents into the arteries

24

What do stents do?

Keep the arteries open do blood can pass through

25

What are the advantages of stents?

They lower the risk of a heart attack

26

What are the disadvantages of stents?

Over time the artery can narrow again which makes the stent irritate the artery so scar tissues grows, and the patient has to take drugs to stop blood clots

27

What is artificial blood?

A blood substitute which is normally a salt solution (saline) which is used to replace blood which has been lost and help keep people alive and allow them to replace their red blood cells

28

What are the advantages of an artificial heart?

Less likely to be rejected by body's immune system and reduces need for heart donors

29

What are the disadvantages of an artificial heart?

Surgery to fit it can cause bleeding and infection, artificial hearts don't work as well as natural ones, it can fail, blood doesn't flow as smoothly so can lead to strokes and patient had to take blood thinking drugs