Unit 3.1.5 - The Heart Flashcards Preview

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Flashcards in Unit 3.1.5 - The Heart Deck (55)
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1

Which side of your heart pumps deoxygenated blood?

Right side

2

Which side of you heart pumps oxygenated blood?

Left side

3

What is meant by a double circulatory system?

The blood flows through the heart twice during each circuit around the body

4

What are the two sections in the double circulatory system?

Pulmonary circulation and systemic circulation

5

Where does the pulmonary circulation take the blood?

From the heart to the lungs and back again

6

Where does the systemic circulation take the blood?

From the heart to the rest of the body and back again

7

On a diagram is the left side the left or right side of the heart and why?

The left side on the diagram would be the right side of the heart as it is reversed

8

Label the diagram of the heart?

See flash card 20

9

What is the name of the valve between the atriums and ventricles?

Atrioventricular valve

10

What is the name of the valve between the ventricles and the arteries that leave the heart?

Semi-lunar valve

11

What vein enters the heart with deoxygenated blood and what artery takes it to the lungs?

Vena cava, pulmonary artery

12

What vein enters the heart with oxygenated blood and what artery takes it to the rest of the body?

Pulmonary vein, aorta

13

How is the left ventricle adapted and why?

It has the thickest muscular walls because it needs to be able to pump the blood more powerfully around the body

14

Why are ventricles thicker than the artia?

Because they have to pump blood out of the heart instead of just of short distance down into the ventricles

15

What are the functions of the valves in the heart?

To stop blood from flowing backwards

16

Why are there cords attached to the atrioventricular valves?

To stop the valves being forces into the atria when the ventricles contract

17

If there is a higher pressure before a valve is it opened or closed?

Opened

18

If there is a lower pressure before a valve is it opened or closes?

Closed

19

What is the contraction and relaxation of the heart muscle known as?

Contraction - systole
Relaxation - diastole

20

What is a systole?

Contraction of the heart muscle

21

What is a diastole?

Relaxation of the heart muscle

22

What three stages can the cardiac cycle to simplified into?

Ventricles relax and atria contract, ventricles contract and atria relax and then ventricles and atria relax

23

Describe the 4 steps that happen when the ventricles relax and atria contract?

1.) The volume of the atria decreases
2.) This increases the pressure in the atria
3.) This forces the atrioventricular valve open
4.) And the blood moves into the ventricles down the pressure gradient

24

Describe the 5 steps that happen when the ventricles contract and atria relax?

1.) The volume of the ventricles decrease
2.) This increases the pressure in the ventricles
3.) As the pressure is now higher in the ventricles than the atria the atrioventricular valves shut
4.) However it forces then semi lunar valves open
5.) And the blood then moves out of the heart through the arteries down the pressure gradient

25

Describe the 3 steps that happen when the ventricles and atria relax?

1.) The higher pressure in the arteries forces the semi lunar valves shut
2.) Blood then returns to the heart again due to the higher pressure in the veins
3.) The cycle starts again

26

What is meant by the cardiac muscles being myogenic?

It can contract and relax without receiving signals from nerves

27

What two nodes control the heart beat?

Sino atrial node and the atrioventricular node

28

What can you shorten sino atrial node and the atrioventricular node to?

SAN and AVN

29

What does the SAN do and what does this cause?

Sends out regular waves of electrical activity to the atrial walls and the AVN, the waves to the atrial walls cause the left and right atria to contract at the same time

30

What prevents the ventricles contracting as well as the atria after the SAN sends out a wave of electrical activity?

There is a band of non conducting collagen tissue between the atria and ventricles which means the waves can't reach the ventricles