Heart stuffs

Question 1

Pulmonary circuit

Answer 1

Pumps deoxygenated blood from heart to lungs and returns O2 rich blood from lungs

Question 2

systemic circuit

Answer 2

pumps O2 rich blood around body and returns O2 poor blood to heart

Question 3

fibrous pericardium

Answer 3

outer layer of heart that provides strength and resistance

Question 4

serous pericardium

Answer 4

contains two laters visceral (epicardium) and parietal layer outer layer

Question 5

pericardial cavity

Answer 5

between the two layers of serous pericardium (visceral and parietal) layer of fluid

Question 6

Heart layers

Answer 6

-epicardium (visceral)
-myocardium
-Endocardium

Question 7

Heart muscle tissue

Answer 7

They are interconnected (intercalated discs)
-very high in mitochondria and myoglobin
-also very vascularized

Question 8

Functional syncytium

Answer 8

Group of heart muscle cells that function together as result of their gap junctions

Question 9

Conduction fibers

Answer 9

Very rapidly project APs through the myocardium

Question 10

Sinoatrial node

Answer 10

SA node is superior in the right ventricle and is the “pacemaker”

Question 11

Atrioventricular node

Answer 11

AV node passes on signal but adds delay for atrial contraction

Question 12

Conduction pathway

Answer 12

1.SA node
2.Internodal pathway to AV
3.AV delay
4.Atrioventricaular bundle (bundle of His)
5.Splits right and left
6.Purkinje fibres reach far sections of ventricle

Question 13

Phase 0

Answer 13

Increased Na+

Question 14

Phase 1

Answer 14

Na+ permeability stops

Question 15

Phase 2

Answer 15

Ca+ fast channels open
K+ close

Question 16

Phase 3

Answer 16

K+ channels open for fast repolarization
Ca+ channels close

Question 17

Phase 4

Answer 17

Resting potential

Question 18

Heart efficiency variability

Answer 18

ANS effects SA, AV node to effect rate and cardiac cells and muscle to effect force

Question 19

Cardioacceleratory center

Answer 19

in medulla this activates sympathetic neurons for NE release

Question 20

Cardioinhibitory center

Answer 20

Activates parasympathetic neurons and triggers vagus nerve

Question 21

Approx Blood volume in arteries

Answer 21

30-35%

Question 22

Approx blood volume in veins

Answer 22

65-70%

Question 23

Vein distension

Answer 23

Much more than arteries, up to 8 times (capacitance vessels) working as reservoirs for blood

Question 24

Layers of blood vessels (generally)

Answer 24

Adventitia (outside)
Media (muscle)
Intima (inner endothelium)

Question 25

What happens when blood vessels are cut?

Answer 25

Veins will collapse but arteries likely keep their shape

Question 26

Notable differences between veins and arteries

Answer 26

Veins can have one way values Arteries have an inner and external elastic membrane separating the sections

Question 27

Artery types

Answer 27

-Elastic arteries (nearest the heart) -Muscular arteries (Not near the heart closer to the tissues) -arterioles

Question 28

Elastic arteries

Answer 28

BV nearest the heart 2.5cm -provide recoil during distole to push blood -eg Aorta, Brachiocephalic trunk, Pulmonary trunk

Question 29

Muscular arteries

Answer 29

have a very thick media section, will be most of the other arteries not hear the heart

Question 30

Arterioles

Answer 30

small arteries with very thin adventitia and incomplete muscle

Question 31

Capillaries

Answer 31

very small blood vessels only having the intima layer.

Question 32

Continuous BV

Answer 32

Complete endothelial lining allow for gas exchange

Question 33

Fenestrated BV

Answer 33

Endothelia not complete with fenestrations to let larger molecules through

Question 34

Sinusoidal BV

Answer 34

AKA discontinuous capillaries as endothelium is not complete with large pores

Question 35

Lymphatic return to blood

Answer 35

via the thoracic duct going to the right atrium

Question 36

ascending aorta

Answer 36

Right above the heart this has the coronary vessels branching from it. It becomes the aortic arch

Question 37

Aortic arch

Answer 37

the top of the aorta where it branches off to the systemic circuit becomes the decending aorta

Question 38

aortic arch branches

Answer 38

in order 1.brachiocephalic trunk 2.Left common carotid artery 3.Left subclavian artery 4.Descending aorta

Question 39

Brachiocephalic trunk branches

Answer 39

Becomes the right subclavian artery and the right common carotid

Question 40

Right subclavian branches

Answer 40

After the brachiocephalic trunk it becomes the 1.Right vertebral 2.Right thyrocervical trunk 3.Right internal thoracic

Question 41

Right axillary artery

Answer 41

the right subclavian becomes this, this continues down the arm

Question 42

right brachial artery

Answer 42

One of the artery branches traveling down the arm from the right axillary, becomes the right radial and ulnar.

Question 43

Left coronary artery

Answer 43

larger in diameter than the right one -Larger to feed the left ventricle

Question 44

Right coronary artery

Answer 44

Smaller in diameter than the left one -Has atrial branches to feed right atrium

Question 45

Coronary sinus

Answer 45

Deoxygenated return to the right atrium from coronary sinuses.