Unit 1: Section 5 - Circulatory System

Question 1

The right side of the heart pumps what blood to were?

Answer 1

Deoxygenated to the lungs

Question 2

The left side of the heart pumps what blood to were?

Answer 2

Oxygenated to the body

Question 3

Where does deoxygenated blood enter the heart?

Answer 3

Vena cava

Question 4

Where does deoxygenated blood leave the heart?

Answer 4

Pulmonary artery

Question 5

Where dos oxygenated blood enter the heart?

Answer 5

Pulmonary vein

Question 6

Where does oxygenated blood leave the heart?

Answer 6

Aorta

Question 7

Are the atriums or ventricle at the bottom of the heart?

Answer 7

Ventricles

Question 8

What valves control what blood enter the ventricles?

Answer 8

Atrioventricular valves

Question 9

What valves control what blood leaves the ventricles?

Answer 9

Semi-lunar valves

Question 10

On the drawing what side will the right atrium be on?

Answer 10

The left hand side

Question 11

Where are cords attached in the heart and what is their purpose?

Answer 11

They attach the atrioventricular valve to the ventricles to stop them being forced up into the atria when the ventricles contract

Question 12

Why does the left ventricle have a thicker more muscular wall?

Answer 12

Because it needs to contract powerfully to pump blood all the way around the body

Question 13

Why do the ventricles have thicker walls than the atria?

Answer 13

Because they need to pump blood out of the heart where as the atria just need to pump it a small distance

Question 14

Why are there valves in the heart?

Answer 14

To stop blood from flowing backwards

Question 15

What happens when there is higher pressure behind a valve and when there is higher pressure in front of the valve?

Answer 15

Forced open

Forced shut

Question 16

What does the cardiac muscle is myogenic mean?

Answer 16

It can contract and relax without receiving signals from nerves

Question 17

What is the pace maker of the heart called

Answer 17

Sino atrial node (SAN)

Question 18

How does the SAN make the left and right atria contract at the same time?

Answer 18

It sends out regular electrical waves to both atrial walls, which causes them to both contract

Question 19

Why are the electrical impulses passed from the SAN to the AVN?

Answer 19

There is non conducting tissue preventing the electrical waves reaching the ventricles, so to get these to contract the waves have to be passed to the AVN.

Question 20

What does AVN stand for?

Answer 20

atrioventricular node

Question 21

How does the AVN make the ventricles contract?

Answer 21

It passes the electrical waves down the bundle of His, which passes it onto the finer muscle fibres called the Purkyne fibres. The purkyne fibres carry the electricl impulse tot the left and right ventricular walls and causes them to contract

Question 22

Why is there a delay before the AVN reacts?

Answer 22

To make sure the ventricle contract after the atria are emptied

Question 23

What is cardiac output?

Answer 23

The volume of blood pumped by the heart per minute

Question 24

What is the formula for cardiac output?

Answer 24

Cardiac output = stroke volume x heart rate

Question 25

What is heart rate?

Answer 25

The number of heart beats per minute

Question 26

What is stroke volume?

Answer 26

The volume of blood pumped during each heartbeat

Question 27

What three stages can the cardiac cycle be simplified into?

Answer 27

1. ) ventricles relax, atria contract 2. ) ventricles contract, atria relax 3. ) ventricles relax, atria relax

Question 28

Why is blood forced into the ventricles when the atria contract?

Answer 28

It decreases the volume of the chamber, increasing the pressure pushing the blood through the valves into the ventricles

Question 29

What happens when the ventricles contract?

Answer 29

It decreases the volume of the chamber, increasing the pressure, forcing the atrioventricular valves shut, forcing the semi lunar valves opening, forcing the blood out of the arties?

Question 30

Is it vein or arties that take blood to the heart?

Answer 30

Veins - to the heart | Arteries - away

Question 31

What happens when both the ventricles and atria relax?

Answer 31

Higher pressure in the pulmonary artery and the aorta force the semi lunar valve shut. Higher pressure in the vena cava and pulmonary vein means the atriums begin to fill with blood again, meaning the cycle can start again

Question 32

A cardiac contraction is also called a?

Answer 32

systole

Question 33

A cardiac relaxation is also called a?

Answer 33

diastole

Question 34

What I cardiovascular disease?

Answer 34

Diseases that are associated with the heart and blood vessels

Question 35

Name three common cardiovascular diseases?

Answer 35

aneurysm, thrombosis, myocardial infarction

Question 36

How is an atheroma formed?

Answer 36

If damage occurs to the endothelium in an artery (could be due to high blood pressure), white blood cells, dead cells, connective tissue and lipids begin to clump together under the lining. Over time more stuff gets deposited and it builds up and hardens to form an atheroma.

Question 37

How can an atheroma lead to an aneurysm?

Answer 37

The atheroma damages and weakens the arties, and the narrower lumen increasing blood pressure. When high pressure blood travels through the weakened artery it may push the inner layers of the artery through the outer elastic layers forming an aneurysm.

Question 38

Thrombosis is he formation of a ?

Answer 38

Blood clot

Question 39

How can an atheroma lead to thrombosis?

Answer 39

If the atheroma bursts through the endothelium it leaves a rough surface, this causes platelets and fibrin to accumulate forming a blood clot.

Question 40

What causes a myocardial infarction?

Answer 40

If a coronary artery becomes blocked (by a blood clot)part of the heart will be cut off from its blood supply and will receive no oxygen. This causes the myocardial infarction

Question 41

What does myocardial infarction mean?

Answer 41

Heart attack

Question 42

What are coronary arteries ?

Answer 42

Arties that supply the heart with blood

Question 43

What are three symptoms of a heart attack?

Answer 43

Pain in chest and upper body, shortness of breath and sweating

Question 44

What is coronary heart disease?

Answer 44

When the coronary arties have lots of atheroma's in them, restricting blood flow and causing blood clots

Question 45

Why does a high blood pressure cause an increases risk in atheroma formation?

Answer 45

An increase in blood pressure means there is more risk of damage to the endothelium so it is more likely an atheroma will form

Question 46

Name three things that can increase blood pressure?

Answer 46

Being over weight, not exercising and excessive alcohol consumption

Question 47

Why does high blood cholesterol level increases the risk of an atheroma formation?

Answer 47

Cholesterol is one of the main parts of the fatty deposits in the atheroma so more fatty deposits more atheroma's

Question 48

Why does salt increase the risk of atheroma formation?

Answer 48

It increases blood pressure

Question 49

What found in cigarettes increases the risk of myocardial infarction?

Answer 49

Carbon monoxide and nicotine

Question 50

Why does carbon monoxide increase the risk of myocardial infarction?

Answer 50

Combines with the haemoglobin and reduces the amount of oxygen transported in the blood, so reduces the amount of oxygen available to the heart which could lead to a heart attack

Question 51

What else does smoking do to the blood which leads to an increase risk of myocardial infarction and why?

Answer 51

Decreases the amount of antioxidants in the blood (important from protecting cells from damage) meaning the endothelium is more easily damaged increasing the chance of atheroma formation and so myocardial infarction

Question 52

What risk factor of coronary heart disease cant you control?

Answer 52

Genetics which might make you more likely to get the disease