6.2 The Blood System

Question 1

what direction do arteries carry blood in relation to the heart

Answer 1

arteries carry blood AWAY from the heart

Question 2

describe the physical structure of an artery

Answer 2

• Thick layer of muscle to help move blood through vessek

- layer of elastic collagen fibres

Question 3

what is the purpose of an arteries elastic collagen fibres?

Answer 3

for expanding and contracting

Question 4

what direction do veins carry blood in relation to the heart?

Answer 4

veins carry blood TOWARDS the heart

Question 5

all veins are structured with valves; what are these valves for?

Answer 5

to prevent backflow of blood (keep it going in one direction)

Question 6

Explain why the walls of the ventricle are thicker than the atrium

Answer 6

• they have to pump blood all the way from the heart to far reaches of the body
• to produce enough pressure to carry blood

Question 7

Why is the left ventricle thicker than the right?

Answer 7

it has to pump blood all the way to the rest of the body

Question 8

what did William Harvey discover?

Answer 8

He discovered the function of the heart and circulation of blood

Question 9

is the blood in the aorta oxygenated or deoxygenated?

Answer 9

oxygenated

Question 10

is the blood in the left ventricle oxygenated or deoxygenated?

Answer 10

oxygenated

Question 11

is the blood in the pulmonary artery oxygenated or deoxygenated?

Answer 11

deoxygenated

Question 12

Which vessel directly supplies the heart muscle with blood?

Answer 12

the coronary artery

Question 13

what is the role of the pacemaker or the SAN (sinoatrial node)

Answer 13

to originate excitation in myogenic muscle

Question 14

describe the term myogenic

Answer 14

originating in muscle tissue

Question 15

explain the roles of the atrium and the ventricles in pumping of blood

Answer 15

Atria collect blood from veins
(althea collects mud from spain… dont ask)
Collect blood while ventricles are contracting
Ventricles pump blood into arteries
ventricles pump blood at high pressure because of their thicker muscular walls

Question 16

explain how the structure of an artery allows it to carry out its function effectively ( I know there are heaps of dot points so try and recall only 3 at a time)

Answer 16

• thick wall to withstand high blood pressures/avoid bursting/leaks;
• many muscle fibres to help pump blood;
• many elastic fibres to stretch and pump blood after each heart beat;
• narrow lumen to maintain high pressure/because blood flows along rapidly;
• thick outer layer of collagen to give strength/prevent aneurism;
• no valves as pressure is high enough to prevent backflow;
• endothelium/smooth inner lining to reduce friction

Question 17

Trace the blood flow through the blood vessels as it serves tissues throughout the body

Answer 17

heart, large artery, smaller artery branch, arterioles, larger vein, largest vein, heart, lungs, heart