Paper 1 Cardiovascular System

Question 1

Myogenic

Answer 1

The capacity of the heart to generate its own electrical impulse

Question 2

Diastole

Answer 2

The relaxation phase of cardiac muscle where the atria and ventricles relax, they expand drawing blood into the atria

Pressure in the atria increases, opening AV valves

Blood passively enters the ventricles

Do valves are closed to prevent blood from leaving the heart

Question 3

Atrial Systole

Answer 3

The contraction phase of cardiac muscle when the atria contract, forcing remaining blood into the ventricles

Question 4

Stroke volume

Answer 4

The volume of blood ejected from the left ventricle per beat

Question 5

Cardiac output

Answer 5

Volume of blood ejected from left ventricle per minute

Question 6

Venous return

Answer 6

The volume of blood returning to the right atria through the veins

Question 7

Cardiac control centre

Answer 7

A control centre in the medulla oblongata responsible for HR regulation

Question 8

Sympathetic nervous system

Answer 8

Part of the automatic nervous system responsible for increasing HR, specifically during exercise.

Question 9

Parasympathetic nervous system

Answer 9

Part of the automatic nervous system responsible for decreasing HR, specifically during recovery

Question 10

Vascular shunt

Answer 10

The redistribution of cardiac output

Question 11

Sternocleidomastoid muscle

Answer 11

Long muscle at the side of neck

Question 12

Ventricular systole

Answer 12

• The ventricles contract, increasing the pressure closing the AV valves to prevent backflow into the atria
• SL valves are forced open as blood is ejected from the ventricles into the aorta and pulmonary artery

Question 13

Conduction system order

Answer 13

• Sino- atrial node
• Atrial ventricular node
• Bundle of his
• Purkinje fibres

Question 14

Bradycardia

Answer 14

A resting heart rate below 60 bpm

Very efficient hearts

Protective effect against cardiovascular and coronary heart disease

Question 15

Three types of heart rate regulation

Answer 15

• Neural control
• Intrinsic control
• Hormonal control

Question 16

Neural control

Answer 16

• Chemoreceptors located in the muscles, aorta and cartoid arteries inform the CCC of chemical changes in the blood stream, such as increased co2 and lactic acid
• Proprioceptors located in the muscles, tendons and joints inform the CCC of motor activity
• Baroreceptors located in the blood vessel walls inform the CCC of increased blood pressure

Question 17

Intrinsic control

Answer 17

• Temperature changes will affect the viscosity (thickness) of the blood and speed of nerve impulse transmission
• Venous return changes will affect the stretch in the ventricle walls, force of ventricular contraction and therefore stroke volume

Question 18

Hormonal control

Answer 18

• Adrenaline and noradrenaline are released from the adrenal glands increasing the force of ventricular contraction (therefore SV) and increasing the speed of electrical activity through the heart (therefore HR)

Question 19

Vasodilate

Answer 19

Widening of arteries, artérioles and pre capillary sphincters

Question 20

Vasoconstrict

Answer 20

Narrowing of arteries, artérioles and pre capillary sphincters

Question 21

Blood pooling

Answer 21

Accumulation of blood in the veins due to gravitational pull and lack of venous return

Question 22

Artérioles

Answer 22

Blood vessels carrying oxygenated blood from the arteries to the capillary beds, which can vasodilate and vasoconstrict to regulate blood flow

Question 23

Pre capillary sphincters

Answer 23

Rings of smooth muscles at the junction between arterioles and capillaries, which can dilate it constrict to control blood flow stheough the capillary bed.

Question 24

How age affects Vo2 max

Answer 24

After the age of 25, vo2 max decreases by 1% per year.

Regular physical activity can help to offset this decline.

Question 25

How gender affects vo2 max

Answer 25

Women:
- Generally have 15-30% lower vo2 max than men

This takes into account differences in body weight.

With straight like for like comparisons, the difference is even greater

Question 26

Training status affect on vo2 max

Answer 26

Athletic training can alter a persons vo2 max by as much as 20% depending on their lifestyle and fitness habits

Question 27

Conduction system - Sino atrial node

Answer 27

Located in the right atrial wall

The SA node generates its own electrical impulses that pass through the muscular walls, forcing them to contract

The SA node is more commonly known as the “pacemaker” as the firing rate will determine heart rate

Question 28

Conduction system - Atrio-ventricular node

Answer 28

The AV node collects the impulse and delays it for approximately 0.1 seconds to allow the atria to finish contracting.

It then releases the impulse to the Bundle of His

Question 29

Conduction system - Bundle of His

Answer 29

Located in the septum of the heart

The bundle of His splits the impulse in two, ready to be distributed through each separate ventricle

Question 30

Conduction system - Bundle Branches

Answer 30

These carry the impulse to the base of each ventricle

Question 31

Conduction system - Purkyne fibres

Answer 31

These distribute the impulse through the ventricle walls, causing them to contract

Question 32

Effects of regular training on lifestyle diseases on the cardiovascular system

Answer 32

• Reduced levels of blood lipids (fats) and overall cholesterol and increase the proportion of HDL to LDL cholesterol
• This will slow the development of atherosclerosis
• Increased coronary circulation (blood flow around the heart) as coronary artérioles gain an increased diameter and density
• This will help to reduce the incidence of heart attacks

Question 33

What is the name of the main vein in the body

Answer 33

Vena Cava

Question 34

Veno constriction

Answer 34

Narrowing/constriction of veins

Question 35

Veno dilation

Answer 35

Widening/dilating of veins