cardio anatomy

Question 1

what is the coronary circulation?

Answer 1

coronary blood vessels run in a ring around the top of the heart and the coronary arteries supply the myocardium with blood

supplies blood to and provides drainage from the tissues of the heart

Question 2

what happens in the pulmonary circuit?

Answer 2

• blood gains oxygen and lose carbon dioxide
• transports oxygen-poor blood from the right ventricle to the lungs
• transports oxygen rich blood from the lungs to the left atrium

Question 3

what happens in the systemic circuit?

Answer 3

• blood loses oxygen and gains carbon dioxide
• transports oxygen-poor blood from the body tissues to the right atrium
• transports oxygen-rich blood from the left ventricle to the body tissue

Question 4

what tissue are capillaries made from and how does it help?

Answer 4

capillaries are made from simple squamous epithelium - this allows small substances like oxygen and nutrients to diffuse easily between the blood and the interstitial fluid

Question 5

what happens during vasodilation?

Answer 5

• blood flow through blood vessels increases
• lumen becomes wider
• smooth muscle in blood vessel wall relaxes

Question 6

what happens during vasoconstriction?

Answer 6

• blood flow through the blood vessels decreases
• lumen becomes narrower
• smooth muscle in blood vessel wall contracts

Question 7

describe what Tunica Externa is and the type of tissue it is

Answer 7

• outer layer which anchors the blood vessels to surrounding structures
• it is connective tissue/collagen fibres

Question 8

describe Tunica Media and what type of tissue it is?

Answer 8

• middle layer that can alter the diameter of the blood vessel
• smooth muscle + sheets of elastin

Question 9

describe Tunica Intima and what type of tissue it is?

Answer 9

• smoother, inner lining that minimises friction as blood moves over it
• simple squamous epithelium

Question 10

describe lumen

Answer 10

the space in the centre of the blood vessel where blood flows

Question 11

blood vessels moving TOWARDS the heart becomes..

Answer 11

the blood vessels become larger - capillaries join from venues which join to form small veins then larger veins

Question 12

blood vessels moving AWAY from the heart become..

Answer 12

the blood vessels become smaller - larger arteries split to become small arteries which split again to become arterioles then capillaries

Question 13

what are the semilunar valves and what do they do?

Answer 13

• aortic & pulmonary semilunar

- they prevent blood that has been ejected into the arteries from returning to the ventricles

Question 14

in what order do electrical impulses pass through the Intrinsic Conduction System of the heart?

Answer 14

1. Sinoatrial (SA) node (pacemaker)
2. Internal pathway
3. atrioventricular (AV) node
4. atrioventricular (AV) bundle
5. bundle branches
6. purkinje fibres

Question 15

what forms the Intrinsic Conduction System?

Answer 15

special nerve fibres run through the walls of the heart providing a pathway for the electrical impulses that cause the myocardium to contract

Question 16

what are the AV valves and what do they do?

Answer 16

• tricuspid & bicuspid valves
• blood returning to the heart fills the atria, putting pressure on the superior sides of the valves causing them to open
• their cusps move superiorly and meet causing them to close, preventing blood flowing back

Question 17

does the atria contract before or after the ventricles?

Answer 17

before

Question 18

where is the heart located?

Answer 18

it is located in the thoracic cavity, medial to the lungs and superior to the diaphragm

apex of the heart is directed towards your left hip

Question 19

what do blood vessels do?

Answer 19

they are tubes that transport blood to and away from all cells

Question 20

what is the order of the heart walls from the chamber to the outside

Answer 20

OUTSIDE
Parietal pericardium
Pericardial cavity
Visceral pericardium
Myocardium
Endocardium
Heart Chamber
INSIDE

Question 21

describe the Parietal Pericardium

layer of the heart wall

Answer 21

• double layered, fluid-filled sac surrounding the heart

- though outer layer that anchors the heart to surrounding structures and prevents it from overfilling

Question 22

describe the Visceral Pericardium

layer of the heart wall

Answer 22

• double layered, fluid-filled sac surrounding the heart
• a serous membrane that secrets a lubricating fluid
• inner layer in contact with the heart

Question 23

describe the Myocardium

layer of the heart wall

Answer 23

• middle layer of the heart wall formed by cardiac muscle

- contracts, creating a force that moves blood through and out of the heart

Question 24

describe Endocardium
(layer of the heart wall)

Answer 24

• simple squamous epithelium and thin connective tissue that lines the chamber of the heart
• creates a smooth, frictionless surface for blood to move over

Question 25

what happens during Turbulent Flow?

Answer 25

• when the blood must flow through an abrupt change in vessel size or where it must flow past a partial obstruction
• turbulence dramatically increases resistance

Question 26

what is Laminar Flow?

Answer 26

• parts of blood vessels where there are fewer branches or obstructions
• the flow is smooth

Question 27

what would decrease the resistance of blood flow?

Answer 27

• decreased haematocrit
• decreased in blood vessel length
• vasodilation

Question 28

what would increase the resistance of blood flow?

Answer 28

• increased haematocrit
• increased in body mass
• vasoconstriction
• dehydration

Question 29

if a blood vessel is vasoconstrictor, what will the resistance & blood flow be?

Answer 29

• more resistant

- reduced blood flow

Question 30

if a blood vessel is vasodilated, what will the resistance & blood flow be?

Answer 30

• less resistances

- increased blood flow

Question 31

what is blood flow?

Answer 31

it is the volume of blood passing through a vessel, organ or the entire circulation in a given period of time