chapter 42 part 2

Question 1

systole

Answer 1

the ventricular contraction, or pumping

Question 2

diastole

Answer 2

the ventricular relaxation, or filling

Question 3

4 valves prevent

Answer 3

back flow of blood in the heart

Question 4

av valves:

Answer 4

tricuspid and bicuspid, separate each atrium and ventricle

Question 5

what is the semilunar valves composed of?

Answer 5

pulmonary and aortic

Question 6

what do semilunar valves do?

Answer 6

control blood flow to the aorta and the pulmonary artery

Question 7

SA node is

Answer 7

peacemaker of heart

Question 8

some cardiac muscles are

Answer 8

autorythmic

Question 9

some cardiac muscles are autorythmic. what does that mean?

Answer 9

they contract without any signal from the nervous system

Question 10

which are autorythmic cardiac muscles?

Answer 10

sa node, av node, and purkinje fibers

Question 11

sa node, av node, purkinje fibers are the auto rhythmic cardiac muscles that…..

Answer 11

generate and conduct electrical impulses to initiate and regulate the heart contractions

Question 12

electrocardiogram–

Answer 12

impulses that travel during the cardiac cycle can be recorded as an electrocardiogram

Question 13

why does av node have to delay?

Answer 13

to allow atria to fully empty out to ventricle

Question 14

what goes after av node?

Answer 14

bundle of heis which send signals to bundle branches

Question 15

whats primary/ natural pacemaker?

Answer 15

sa node

Question 16

whats the number for sa node?

Answer 16

60-100

Question 17

whats number for av node?

Answer 17

40-60

Question 18

signals from sa node spread thru atria> 1> 2>3

Answer 18

1.signals are delayed at av node
2. bundle branches pass signals to heart apex
3. signals spread thruout ventricles

Question 19

which is 2nd pacemaker of heart?

Answer 19

av node

Question 20

where is sa node only found?

Answer 20

in right atrium

Question 21

what does sa node do?

Answer 21

spreads signals within right atrium and left atrium

Question 22

bundle of his=

Answer 22

av bundle

Question 23

whats purkinje fibers?

Answer 23

muscular layer of heart and contracts the ventricles

Question 24

the autorythmic cardia muscles, including:

Answer 24

sa node> av node> av bundle/ bundle of his> bundle branches> purkinje fibers

Question 25

the pacemaker is related by 2 portions of the nervous system:

Answer 25

the sympathetic and parasympathetic

Question 26

what does the sympathetic division do?

Answer 26

speeds up the pacemaker

Question 27

what does the parasympathetic division do?

Answer 27

slows down the pacemaker

Question 28

pacemaker is also regulated by-----

Answer 28

hormones thru the autonomic nervous system

Question 29

autonomic nervous system

Answer 29

uses hormones like epinephrine and acetylcholine

Question 30

whats epinephrine?

Answer 30

adrenaline to increase heart rate, sympathetic

Question 31

whats acetylcholine?

Answer 31

to decrease heart rate, parasypthetic

Question 32

inner= middle= outer=

Answer 32

endotherm muscular adventitia also have connective tissue

Question 33

how many layers does arteries and veins have?

Answer 33

3 layers

Question 34

how many layers does capillaries have?

Answer 34

1 layer- no inner and outer, only 1 layers known as endothelium

Question 35

what does veins have?

Answer 35

valve to ensure that the blood flows in only one direction, toward the heart

Question 36

whats the function of valves within veins?

Answer 36

to ensure that blood flows in only one direction, toward the heart

Question 37

what does arteries and veins have?

Answer 37

an endothelium, smooth muscle, connective tissue/ adventitious

Question 38

who has thicker walls arteries or veins? why?

Answer 38

arteries have thicker walls than veins to accommodate the high pressure of blood pumped from the heart

Question 39

what happens in the inner walled veins?

Answer 39

blood flows back to the heart mainly as a result of muscle action

Question 40

changes in blood pressure during the cardiac cycle:

Answer 40

systolic pressure and diastolic pressure

Question 41

what is systolic pressure?

Answer 41

the pressure in arteries during ventricular systole; it is the highest pressure in the arteries

Question 42

what is diastolic pressure?

Answer 42

the pressure in the arteries during diastole; it is lower than systolic pressure

Question 43

which more dangerous systolic pressure or diastolic pressure?

Answer 43

diastolic pressure

Question 44

what is a pulse?

Answer 44

a rhythmic bulging of artery walls within each heartbeat

Question 45

what does homeostatic mechanisms?

Answer 45

regulate arterial blood pressure by altering the diameter of arterioles

Question 46

vasoconstriction===

Answer 46

contraction of smooth muscle in arteriole walls; it increases blood pressure

Question 47

vasolidation===

Answer 47

relaxation of smooth muscles in the arterioles; it causes blood pressure to fall

Question 48

whats hg?

Answer 48

mercury

Question 49

whats the blood pressure for a healthy 20 year old human at rest?

Answer 49

120 mm Hg at systole and 80 mm Hg at diastole

Question 50

fainting is caused by ----

Answer 50

an adequate blood flow to the heart

Question 51

what do animals with a very long neck require?

Answer 51

a. very high systolic pressure to pump blood A great distance against gravity

Question 52

what do one way valves in veins do?

Answer 52

prevent back flow of blood

Question 53

blood capillaries constantly -----

Answer 53

leak a small amount of fluid and proteins into the surrounding tissues due to the pressure within them

Question 54

what does lymphatic system do?

Answer 54

collects this excess fluid, now called lymph, and returns it to the bloodstream to prevent it from accumulating in the tissues, which wld case swelling (edema)

Question 55

what do valves in lymph vessels do?

Answer 55

prevent the back flow of fluid

Question 56

what are lymph nodes?

Answer 56

organs that filter lymph and play an important role in the body's defense