The Heart - Anatomy and Physiology

Question 1

How is the structure of the heart affected by Athlete’s Heart?

Answer 1

increased chamber wall thickness and cavity size

Question 2

How is the function of the heart affected by Athlete’s Heart?

Answer 2

enhanced diastolic filling, augmentation of stroke volume

Question 3

How is the electricity of the heart affected by Athlete’s Heart?

Answer 3

bradycardia, repolarization anomalies, voltage criteria for chamber enlargement

Question 4

What is the pericardial sac?

Answer 4

provides lubrication, covers, and protects the heart

Question 5

What is Pericarditis?

Answer 5

inflamed/infection of pericardium

Question 6

What are some characteristics of the epicardium?

Answer 6

serous membrane including blood capillaries, lymph capillaries, and nerve fibers

Question 7

What is the function of the epicardium?

Answer 7

lubricative outer covering

Question 8

What are some characteristics of the myocardium?

Answer 8

cardiac muscle tissue separated by connective tissues and including blood capillaries, lymph capillaries, and nerve fibers

Question 9

What is the function of the myocardium?

Answer 9

provides muscular contractions that eject blood from the heart chambers

Question 10

What are some characteristics of the endocardium?

Answer 10

endothelial tissue and a thick subendothelial layer of elastic and collagenous fibers

Question 11

What is the function of the endocardium?

Answer 11

protective inner lining of the chambers and valves

Question 12

What are myocytes?

Answer 12

contractile cells of the heart

Question 13

What is connexon?

Answer 13

charges/particles flow through

Question 14

What is a desmosome?

Answer 14

cell adhesion junctions that anchor cell membranes to the intermediate filament network

Question 15

What are some characteristics of myocytes?

Answer 15

Many mitochondria present in myocardial cells, very dense capillary network (~1/fiber), T tubules

Question 16

How many atria? How many ventricles?

Answer 16

2 each

Question 17

Describe the two atria.

Answer 17

walls - 2 thin overlying muscular sheaths
blood reservoirs and pumps

Question 18

Describe the two ventricles

Answer 18

thicker walls than atria
pump blood from the low pressure venous system to the high pressure arterial system
formed by a CONTINUUM of muscle fibers
left ventricle is much thicker than the right

Question 19

Describe the muscle fibers that make up the ventricles.

Answer 19

originate at the base of the heart
sweep towards the apex on epicardial surface
change direction 180 degrees from endocardium and papillary muscle

Question 20

True or false: the right ventricle is larger than the left

Answer 20

False

Question 21

What are the two semilunar valves?

Answer 21

aortic valve and pulmonary valve

Question 22

What is the aortic valve?

Answer 22

sits between left ventricle and aorta

Question 23

What is the pulmonary valve?

Answer 23

sits between the right ventricle and the pulmonary artery

Question 24

How many cusps to the semilunar valves have?

Answer 24

3 each

Question 25

What are the two AV valves?

Answer 25

mitral (or bicuspid) valve and tricuspid valve

Question 26

What is the mitral valve? How many cusps?

Answer 26

between left atria and left ventricle- two cusps

Question 27

What is the tricuspid valve? how many cusps?

Answer 27

on right between right atria- 3 cusps

Question 28

What are the cardiac valves?

Answer 28

thin flaps, each cusp has papillary filaments attached, called Chordae Tendineae

Question 29

What are the thin flaps on cardiac valves?

Answer 29

flexible endothelial covered fibrous tissue
attached at the base to fibrous rings
flaps are twice the size of the opening

Question 30

describe the Chordae Tendineae.

Answer 30

arise from papillary muscles, prevents valves from protruding too far into atria

Question 31

Systole vs Diastole

Answer 31

systole=contraction
diastole=relaxation

Question 32

What results from occlusion of a vessel?

Answer 32

low oxygen or ischemia and necrosis

Question 33

O2 supply to the heart averages __________

Answer 33

8-10 mL/min/100g of heart

Question 34

result from high a-vO2 difference?

Answer 34

increase in O2 demand must be met by increasing flow

Question 35

What nutrients does the heart use for coronary circulation?

Answer 35

fatty acids, some ketone bodies (up to 60%) and (40%) glucose, lactate, or small amounts of pyruvate for fuel

Question 36

Continuous flow to the periphery occurs by:

Answer 36

distension of the aorta and its branches during ventricular contraction (systole)
elastic recoil of walls of large arteries with forward propulsion of blood during ventricular relaxation (diastole)

Question 37

Describe the arterial branches as blood moves rapidly throughout them.

Answer 37

they become more narrow and walls become thinner
change histologically toward the periphery

Question 38

Describe the aorta as blood moves rapidly throughout.

Answer 38

predominantly an elastic structure
peripheral arteries become more muscular until at the arterioles the muscular layer predominates

Question 39

What is the cardiovascular system made up of?

Answer 39

pump, series of distributing and collecting tubes, extensive system of thin vessels