Cardiovascular System 2

Question 1

Function of the cardiovascular system

Answer 1

To provide an adequate circulation of blood around the body

This helps to provide self with oxygen and essential nutrients and to remove waste products from these cells

Question 2

Double Circulatory System

Answer 2

The heart pumps blood twice in one cycle to help maintain a high-pressure and movement of blood

Question 3

Systematic Circulation

Answer 3

Blood flow between the heart and the whole/rest of the body

Question 4

Pulmonary Circulation

Answer 4

Blood flow between the heart and the lungs

Question 5

Cardiac Muscle

Answer 5

The muscle which makes up the heart it never fatigues

Question 6

Myogenic cardiac muscle

Answer 6

Cardiac muscle is myogenic. This means that it can contract and relax on its own accord without the need for nerve impulses as some other muscles do

Question 7

Septum

Answer 7

The muscular wall separating the left and right sides of the heart

Question 8

Left chambers of the heart

Answer 8

the left atrium is above, receiving blood from the PV
and the left ventricle is below, forcing blood out the aorta

Question 9

Right chambers of the heart

Answer 9

the right atrium is above, receiving blood from the vena cava
and the right ventricle is below, forcing blood out the PA

Question 10

Ventricles Vs Atria

Answer 10

The wall of the ventricles are thicker than the walls of the atria. This is because the atria only need to pump blood down to the ventricles whereas the ventricles need to pump blood out of the heart (further distances)

Question 11

Vena Cava

Answer 11

The blood vessel (vein) which carries deoxygenated blood from the body to the heart (right atrium)

Question 12

Aorta

Answer 12

The blood vessel (artery) carrying oxygenated blood from the heart (left ventricle) to the rest of the body

Question 13

Pulmonary Vein

Answer 13

The blood vessel carrying oxygenated blood from the lungs to the heart (left atrium)

Question 14

Pulmonary Artery

Answer 14

The blood vessel carrying deoxygenated blood from the heart (right ventricle) to the lungs

Question 15

Coronary Arteries

Answer 15

Blood vessels found on the surface of the heart which provide the heart muscle with its own blood flow for essential gases & nutrients such as (oxygen and glucose)

Question 16

Atrioventricular Valves

Answer 16

They separate the atria and the ventricles and prevent back flow of blood from the ventricles into the atria (during ventricular systole)

Question 17

Semilunar Valves

Answer 17

Separate the ventricles and the arteries, prevent back flow of blood from the arteries into the heart (during ventricular systole)

Question 18

Opening and closing of valves

Answer 18

The only open one way dependent on the pressure, when pressure is higher behind the valve it is forced open and when pressure is higher in front of a valve it is forced closed this maintains a one directional flow in the heart

Question 19

Cords

Answer 19

Cords are attached to the atrioventricular valves from the ventricles. They stop the ventricles being forced upwards into the atria when the ventricles contract. Therefore preventing blood from back flowing

Question 20

The order of blood flow through the heart

Answer 20

Atrial Systole
Ventricular Systole
Diastole

Question 21

Atrial Systole

Answer 21

Both atria contract in unison, this decreases the volume of the atria and increases the pressure.
This forces the atrioventricular valves to open and blood flows down its pressure gradient into the ventricles causing the ventricles to (slightly) increase in pressure and volume

Question 22

Ventricular Systole

Answer 22

Both ventricles contract in unison, this decreases the volume and increases the pressure in the ventricles.
The higher pressure in the ventricles then the atria causes the AV valves to close
The higher pressure in the ventricles then the arteries forces the semilunar valves to open, blood flows into the arteries.

Question 23

Diastole

Answer 23

All chambers of the heart relax, the arteries higher pressure than the ventricles which forces the semilunar to shut.
Blood flows into the atria slowly filling them up as the veins have slightly more pressure than the atria.
The increase atria pressure causes the AV valves to open and some blood passively flows into the ventricles.

Question 24

Sinoatrial node (SAN)

Answer 24

Found in the right atrium, & releases an electrical signal which coordinates the cardiac cycle and initially results in atrial contraction

(aka the pacemaker)

Question 25

Atrioventricular node (AVN)

Answer 25

Found towards the centre of the heart at the point where all four chambers of the heart are in close proximity.
It releases an electrical signal which is passed on to the bundle of His.

Question 26

Bundle of His

Answer 26

Found in the septum of the heart and carries the electrical signal from the AVN into several separate signals which are sent through the purkinje fibres

Question 27

Purkinje Fibres

Answer 27

Found in the walls of the ventricles, (receive electrical impulses from the bundle of his) and cause ventricles to contract

Question 28

Pathway of electrical signals through the heart

Answer 28

SAN/Sinoatrial Node (RA)
AVN/Atrioventricular Node (Septum)
Bundle of His (Septum)
Purkinje Fibres (walls of ventricles)

Question 29

Decreasing heart rate

Answer 29

Low CO2/high O2 is detected by Chemoreceptors, medulla and carotid arteries.
Impulses are sent to the heart resulting in fewer impulses between the sinoatrial and the AV node this leads to a decreased heart rate

Question 30

Increasing heart rate

Answer 30

High CO2/Low O2 detected by chemoreceptors, medulla and carotid arteries
Impulses sent to the heart result in more impulses between the sinoatrial node and the AV note