A&P CH12

Question 1

flow of blood through the heart

Answer 1

right atrium
tricuspid valve
right ventricle
pulmonary valve
lungs
left atrium
bicuspid valve
left ventricle
aorta
body
right atrium

Question 2

which side of heart is larger? why?

Answer 2

left, it needs to generate more force

Question 3

heart located where?

Answer 3

mediastinum

Question 4

def pericardium

Answer 4

surrounds the heart

Question 5

2 layers of pericardium, and name for first

Answer 5

visceral lines heart (also called epicardium), parietal lines pericardial cavity

Question 6

def auricle

Answer 6

lumpy, wrinkled flap

Question 7

3 layers of heart

Answer 7

epicardium (outer)
myocardium (muscle)
endocardium (inner)

Question 8

which layer of heart contains vessels?

Answer 8

myocardium

Question 9

which layer of heart is smooth epithelium?

Answer 9

endocardium

Question 10

what do gap junctions do?

Answer 10

allow action potentials to move rapidly between cells

Question 11

what divides 2 atria?

Answer 11

interatrial septum

Question 12

what divides 2 ventricles?

Answer 12

interventricular septum

Question 13

what does coronary circulation do?

Answer 13

circulates blood to the heart muscle

Question 14

def anastomoses

Answer 14

alternate pathways for blood flow, assist in blockage situations

Question 15

which cells form bulk of heart’s muscle tissue?

Answer 15

contractile

Question 16

steps to contraction (3)

Answer 16

1. rapid depolarization
2. plateau
3. repolarization

Question 17

why separate firing mechanisms?

Answer 17

backup system to ensure cardiac operation if one part fails

Question 18

def SA node

Answer 18

cardiac pacemaker, electrical signal generated here

Question 19

how fast does SA fire?

Answer 19

70-80 bpm

Question 20

how fast does AV fire?

Answer 20

40-60 bpm

Question 21

how fast do purkinje fibers fire?

Answer 21

20-40 bpm

Question 22

what is the p wave?

Answer 22

caused by depolarization of atria, sa node firing causes a contraction in atria

Question 23

what does QRS complex show?

Answer 23

action potential traveling through ventricles

Question 24

what does T wave show?

Answer 24

ventricular repolarization

Question 25

what is preload?

Answer 25

precontraction level of blood in the heart

Question 26

low preload does what?

Answer 26

makes pumping harder

Question 27

what is stroke volume?

Answer 27

amount ejected by 1 ventricle

Question 28

formula for cardiac output

Answer 28

= stroke volume x heart rate

Question 29

what is the frank-starling principle?

Answer 29

ventricular contractions become more powerful and increase stroke volume as walls stretch

Question 30

ACh release by what?

Answer 30

parasympathetic motor neurons

Question 31

NE released by what?

Answer 31

sympathetic neurons

Question 32

thyroid hormones and glucagon do what?

Answer 32

increase force of contraction

Question 33

def digitalis

Answer 33

increases calcium concentration, and thus force of contraction