chapter 21

Question 1

two circuits

Answer 1

pulmonary and systemic

Question 2

layers in order

Answer 2

fibrous pericardium, parietal pericardium, pericardial cavity, epicardium, myocardium, endocardium

Question 3

pericardial sac

Answer 3

made of the parietal pericardium and fibrous pericardium

Question 4

walls of the heart

Answer 4

epicardium, myocardium and endocardium (internal)

Question 5

myocardium

Answer 5

muscle lining
-aerobic respiration
-intercalated discs that connect cardiocytes

Question 6

epicardium

Answer 6

external surface

Question 7

cardiocytes

Answer 7

contract without information from the CNS
-pace cells
-dont need brain

Question 8

intercalated discs

Answer 8

-cell to cell junction
-desmosomes bind two sarcolemma
-discs bind myofibrils of adjecent cells

Question 9

gap junctions

Answer 9

-bind cells to each other
-pores for ion movement
-ion movement allows the sarcomeres to contract as one

Question 10

elastic sheath

Answer 10

wraps each cardiac cell

Question 11

fibrous sheet

Answer 11

wraps each muscle layer
-separate superficial layer with the deep muscle layer
-encircle the base of the pulm trunk and ascending aorta

Question 12

fibrous skeleton

Answer 12

-elastic sheath and fibrous sheet
-stabalize cardiac cells, heart valves, support nerves and vessels in myocardium, distribute contraction force, prevent overexpansion, recoils heart after contraction, isolate atrial cells from ventricular cells

Question 13

oblique angle

Answer 13

heart sits at one
-inferior border= right ventricle
-right border= right atrium
-heart is also rotated slightly left

Question 14

sternocostal surface

Answer 14

formed by the right atrium and right ventricle

Question 15

posterioir surface

Answer 15

left atrium

Question 16

sulci

Answer 16

are on the external structures of the four chambers
-interatrial, coronary, anterioir intercentricular and posterioir interventricular sulcus

Question 17

interatrial sulcus

Answer 17

separate left and right atria

Question 18

coronary sulcus

Answer 18

separate atria and the ventricles

Question 19

anterioir interventricular sulcus

Answer 19

separatest the left and right ventricles

Question 20

posterioir interventricular sulcus

Answer 20

spearates left and right ventricles

Question 21

l and r atria

Answer 21

have walls, superior to the coronary sulcus, have auricles (extensions)

Question 22

l and r ventricles

Answer 22

inferior to coronary sulcus, right ventricles forms diaphragmatic surface

Question 23

interatrial septums

Answer 23

separate interatrial septum

Question 24

what do the folds of the endocardium form>

Answer 24

atrioventricular valves

Question 25

right atrium

Answer 25

deoxy from svc, ivc and coronary sinus -has pectinate muscle and fossa ovalis

Question 26

fossa ovalis

Answer 26

fetal remnant of the foramen ovale (atrium) -let blood flow from right to left atria

Question 27

right ventricle

Answer 27

deoxy from right atrium through tricuspid

Question 28

muscles of valves

Answer 28

chordeae tendoneae connect to papillary muscles and they prevent valve inversion and backflow

Question 29

right ventricle internal surface

Answer 29

-trabeculae carneae -moderator band -pulmonary valve

Question 30

trabeculae carneae

Answer 30

meaty ridges in the wall the prevent suction during heart beat

Question 31

moderator band

Answer 31

ONE IN THE RIGHT VENTRICLE -muscular bands that come from the interventricular spetum to the ventricular wall -part of the electrical system -prevents overexpansion of thin walled right ventricle

Question 32

left atriums

Answer 32

oxy blood from the pulm veins through bicuspid valve/ mitral valve

Question 33

left ventricle

Answer 33

-thicket walls and highest pressure -send blood through systemic circuit -NO moderator bands -av valve has the chorae tendineae with 2 cusps

Question 34

lung pressure

Answer 34

very low (25) which is why right ventricle walls can be so thin

Question 35

av valves

Answer 35

-have right connective tissue to connect heart tissue, cusps, chordae tendineae and papillary muscles -open bc of pressure in atria

Question 36

papillary muscles

Answer 36

relax

Question 37

ventricular contraction

Answer 37

open semilunar valves

Question 38

coronary vessels

Answer 38

supply heart with blood and branch of the ascending aorta near its base -3 major are right coronary artery, left coronary artery and cardiac veins

Question 39

coronary bloodflow

Answer 39

blood leaves left ventricle through aortic valves, blood surgest into aortic arch and rebounds backwards as the aortic valve shuts, rebound blood fills the coronary arties to supply walls of heart with oxy

Question 40

right coronary artery

Answer 40

passes between the right auricle and pulm trunk

Question 41

widow maker

Answer 41

left anterioir descending artery

Question 42

branches of left coronary artery

Answer 42

-circumflex branch (form left marginal and posterioir left ventricle) -anterioir interventricular branch (anterioir to posterioir branches. anastomoses)

Question 43

Where does the great cardiac vein drain?

Answer 43

coronary sinus

Question 44

cardiac cycles

Answer 44

-periods of relaxation and contraction -systole= contract -diastole= relax

Question 45

diastole

Answer 45

chamber fills with blood

Question 46

systole

Answer 46

blood into ventricles (atrial) blood into pulmonary trunk and ascending aorta (ventricular)

Question 47

conducting cells

Answer 47

-nodal cells and conducting fibers

Question 48

nodal cells

Answer 48

pacemaker ells -estabalish contraction rate -membranes depolarize

Question 49

conducting fiber

Answer 49

-send contractile stimulus to myocardium -impulse from nodes to muscle

Question 50

sinoatrial/ sa node

Answer 50

in posterior wall of right atrium -determines rate

Question 51

tachycardia

Answer 51

rapid rate

Question 52

bradycardia

Answer 52

slow rate

Question 53

internodal pathway

Answer 53

impulse travels to the av node

Question 54

av node

Answer 54

in the floor of the right atriums -impulse from av node to bundle that will divide into the right and left bundle branches tat wil send the impulse to purkinje fibers then to ventricular myocardium

Question 55

first phase contraction

Answer 55

atriole systole not strong enough to open valve

Question 56

heart rate

Answer 56

set by pace maker but controlled by sypathetic and parasympathetic nervous system -autonomic nervous system changes pacemaker activity

Question 57

ne

Answer 57

from sympathetic ns and causes increase heart rate and contraction force

Question 58

acch

Answer 58

from parasympathetic ns, decreases heart rate and force of contractions