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Human Anatomy & Physiology 2 > Heart > Flashcards

Flashcards in Heart Deck (43)
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1
Q

What are the 2 major divisions of the heart?

A

pulmonary

systemic

2
Q

pulmonary circuit (3)

A

right side of the heart
carries blood to lungs
lower pressure

3
Q

systemic circuit (3)

A

left side of the heart
carries blood to the rest of the body
higher pressure

4
Q

pericardium

A

double layered sack surrounding the heart that allows the heart to beat without friction

5
Q

what are the 3 layers of the pericardium?

A

parietal pericardium
visceral pericardium (epicardium)
pericardial cavity

6
Q

parietal pericardium

A

outer, tough layer

7
Q

visceral pericardium (epicardium)

A

inner, thin, smooth

covers the heart surface

8
Q

myocardium

A

electrical nonconductor; muscles and valves attach to this

9
Q

endocardium

A

smooth inner lining of the heart; what blood is touching

10
Q

structure of cardiac muscle (3)

A

short, branched cells
fewer SR
intercalated discs that have electrical junctions

11
Q

What are 3 things needed for the cardiac muscle to be almost exclusively aerobic?

A

rich in myoglobin
large # of mitochondria
large glycogen storage

12
Q

left and right atria

A

receive blood returning to the heart

13
Q

left and right ventricle

A

pump blood into arteries

14
Q

atrioventricular valves right? left?

A

right=tricuspid

left=bicuspid

15
Q

cords connect AV valves to papillary muscles

A

chordae tendineae “heart strings”

16
Q

semilunar valves

A

control flow into great arteries

17
Q

characteristics of the heartbeat? (3)

A

myogenic:electrical activity
autorhythmic
spread of electrical activity follows a particular pathway

18
Q

myogenic

A

electrical activity of heartbeat originates with heart

19
Q

autorhythmic

A

each cell in heart can spontaneously depolarize and contract

20
Q

SA node (2)

A

pacemaker, initiates heartbeat

contains cells that are fastest to spontaneously depolarize

21
Q

_____ and _____ are electrically isolated

A

atria and ventricles

22
Q

steps for conduction of heartbeat?

A

SA node-> AV node->AV bundles(via septum)->purkinje fibers (via moderator band)

23
Q

cardiodynamics

A

movements and forces generated during the cardiac cycle

24
Q

Cardiac Output=

A

Heart Rate * Stroke Volume

25
Q

What is the cardiac output at rest? what does it increase to once there is an increase in CO2?

A

5L/min; 21L/min

26
Q

cardiac reserve

A

difference between a persons max and resting CO

27
Q

when does the cardiac reserve increase?decrease?

A

with fitness; disease

28
Q

what changes cardiac output?

A

changes in heart rate and stroke volume

29
Q

stroke volume=

A

EDV- ESV

30
Q

What are factors that affect the ESV of stroke volume? (3)

A

preload
contractibility
afterload

31
Q

What are factors that affect the EDV of stroke volume?

A

ventricular filling time->faster HB->reduces filling time

venous return

32
Q

Anything that increases blood volume, then ___ ___ increase

A

venous return

33
Q

preload (ESV)

A

degree of muscle stretch before contraction

34
Q

the more blood in the ventricle before contraction, the greater the _____ on the ventricle. The more ____ the longer the ____ can _____

A

stretch; stretch, filament;slide

35
Q

what is responsible for stretching the heart?

A

blood

36
Q

contractibility (ESV)

A

amount of force produced during a contraction at a given preload

37
Q

During contractibility, the increasing amount of ____ ___ in the cardiocytes allows for more sliding filaments

A

free calcium

38
Q

What factors control contractibility? (4)

A

ANS
hormones
drugs
ion concentration

39
Q

afterload

A

the force the contraction ventricle must exceed before blood can be ejected

40
Q

A ____ afterload increases ____ and decreases ___

A

higher; ESV;SV

41
Q

When is afterload increased? (4)

A

constriction of peripheral blood vessels
circulatory blockage
high blood pressure
valve stenosis

42
Q

tachycardia

A

resting adult HR above 100

43
Q

bradycardia

A

resting adult HR below 60