Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

bioscience > heart > Flashcards

heart Flashcards

1
Q

location of heart

A

mediastinum the cavity between 2 pleural cavities and rest on the superior surface of diaphragm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

position of heart

A

posterior to costal cartilage
posterior to sternum anterior to vertebral column
5th ICS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

covering of the heart

A 
parietal pericardium
- fibrous layer
-epithelial layer
pericardial cavity
heart wall
-epicardium
-myocardium
-endocardium
heart chamber
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

components of the heart wall

A

epicardium outermost layer of epithelial tissue
myocardium middle layer of cardiac muscle
endocardium inner layer of endothelial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

internal anatomy

A

left side must generate 4-6 times more pressure to push blood through the systemic circuit compared to the right side and the pulmonary circuit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

heart valve- atrioventricular valve

A

AV-pressure of incoming blood opens valve , blood moves into ventricle
chordae tendineae loose
papillary muscle relaxed
AV valve open when atrial pressure > ventricular pressure
when ventricles contract blood moves upward, pressure increases, thus valve closes
chordae tendineae tense to prevent eversion of valve into atria and back flow of blood
papillary muscle contract to tense chordae tendineae
AV valve closes when atrial pressure< ventricular pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

heart valve- semilunar

A

SL valve open when ventricular pressure > arterial pressure
SL valve open when the ventricles contract and push blood against valve
SL valve close when arterial pressure > ventricular pressure
SL valve close when ventricles relax and blood in arteries attest to move backwards and is caught in the cusps of the valve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

coronary circulation- arteries

A

myocardium doesn’t receive oxygen or nutrients from blood there it gets it from coronary artery
ventricles relax & ventricular pressure drops below arterial pressure, arterial blood flows back towards to the ventricles, as it flows backwards within the aorta it moves into the coronary arteries
left coronary artery gives rise to anterior inter ventricular artery and supplies oxygenated blood to the anterior ventricles
right coronary artery supplies the right atrium and gives rise to the posterior inter ventricular artery which supplies oxygenated blood to the posterior ventricles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

coronary circulation- veins

A

great cardiac veins drains deoxygenated blood from the anterior ventricles
middle cardiac vein drains the posterior ventricles
all veins all drain into the coronary sinus empties into the right atrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

unidirectional pathway

A

SVC, IVC & coronary sinus pass blood to right atrium, into right ventricle via tricuspid valve, into pulmonary trunk via pulmonary SL valve passing pulmonary arteries to the lungs to be oxygenated, It returns to the heart via 4 pulmonary veins, into left atrium, passing mitral valve into ventricle, into the aorta through aortic SL valve, oxygen rich blood is delivered to the body tissues and then returns to the heart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

innervation of the heart

A

mechanical activity of the heart always begins with electrical activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

intrinsic conduction system

A

myocardium includes pacemaker cells:
unstable resting membrane potential
continually depolarise to generate AP
all cardiac muscle cells have special electrical connections , AP can be conducted to adjacent muscle cells and so on, allows coordinated activity of entire myocardium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

pacemaker cells form the intrinsic conduction system

A

sinoatrial node- depolarise
atrioventricular node- depolarise pauses at AV node
atrioventricular bundle- connects atria to ventricles
bundle branches- depolarisation through interventicualr septum
purkinje fibres- depolarise the ventricular myocardium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

extrinsic innervation

A

ANS modify the activity of the heart

cardiac centre of medulla oblongata

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

cardioacceletory centre

A

increases both heart rate and force of contraction

symph input via thoracic spinal cord to the SA and AV nodes, ventricular myocardium, coronary arteries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

cardioinhibitory centre

A

decreases heart rate only

para input via vagnus nerve to the SA and AV nodes ‘slows SA node to 75 depolarisation per minute at rest

17
Q

ECG deflections

A

P wave- depolarisation of atrial myocardium, SA node
QRS complex- depolarisation of ventricular myocardium, atrial depolarisation is masked by the complex
T wave- depolarisation of ventricular myocardium

18
Q

intrinsic

A
  1. starts at SA node and electrical signal spreads throughout atrial myocardium
  2. AV node delay in ES
  3. signal AV bundle, bundle branches apex perkinje fibres depolarise ventricles
  4. depolarisation of the ventricle spread
  5. ventricle repolarise apex move up ventricle
  6. ventricle repolarise
19
Q

cardiac cycle

A 
systole= period of contraction, increased pressure forces blood out of chamber
diastole= period of relaxation, decreased pressure allowing chamber to refill
20
Q

phases of cardiac cycle phase 1

A

all 4 chambers are relaxed mid to late ventricular diastole
AV valve are open, SL valve closes
blood returning to atria moves directly into ventricles, fills ventricles
atrial systole= both atria contract simultaneously, completely filling the relaxed ventricles with blood
atrial systole end and atrial diastole begins and continues until the next cycle

21
Q

phase 2a

A

both ventricles contract beginning at the apex pushing blood upwards and increasing ventricular pressure
upward movement of blood and increased pressure closes the AV valves
ventricular pressure not yet great enough to open SL valves so blood cannot yet exit the ventricles no change in ventricular blood volume
atria in diastole AV valve closed

22
Q

phase 2b

A

increasing force of ventricular contraction ventricular pressure increases above arterial pressure SL valve open
blood ejected into aorta and pulmonary trunk= ventricular ejection
AV valve closed as ventricular pressure is greater than atrial pressure thus blood cannot move backwards
atria in diastole

23
Q

phase 3

A

ventricles relax, ventricular pressure drops below arterial pressure, arterial blood flows backwards, closes the SL valve (s2)
as ventricular pressure is still greater than atrial pressure the AV valve are still closed thus blood cannot move from atria into the ventricles no change in ventricular blood volume
ventricles continue to relax, ventricular pressure drops below atrial pressure AV valve open return to phase 1

24
Q

correlating electrical and mechanical events

A

p= atrial depolarisation trigger atrial systole
qrs complex- ventricular depolarisation tigger ventricle systole
t - ventricular repolarisation results in ventricular diastole

25
Q

cardiac output

A

volume of blood pumped by the left ventricle in one minute

26
Q

factors

A 
HR= number of beats per min
SV= volume of blood ejected from left or right ventricle per min
27
Q

SV

A

SV= EDV-ESV
end diastolic volume= volume of blood in ventricle at the end its relaxation period
end systolic volume= commune of blood remaining in ventricle after it has contracted

28
Q

factors affect EDV

A

venous return= amount of blood returning to the heart from systemic or pulmonary circuits depend on total blood flow and pattern of blood flow determined by muscle/ organ activity, symp activity and body position
passive filling time= time both the atria and ventricles are in diastole
decreases as HR increases
if HR > 200bpm, big decrease in passive felling time,

29
Q

EDV determine preload

A

preload= degree the myocardium is stretched before it contracts, determine force of lenticular contraction
greater EDV, increased preload, more efficient myocardial contraction ,

30
Q

factors affecting ESV

A 
contractility= amount of force produced by myocardial contraction 
contractility increased by: symp NS 
hormones
high levels of extracellular ca
decreased by acidosis 
increased extracellular K levels
31
Q

afterload

A

pressure that ventricles must overcome to open SL valve to eject blood into the arteries
increased by factors restrict flow into arteries
the longer it takes for ventricles to generate enough pressure to open the SL valve, the less time there is for blood ejection

32
Q

HR

A

cardiovascular centre in medulla oblongata
receives input from proprioceptors
chemoreceptors
baroreceptors
autonomic output:
symp cardioacceletory centre NA binding to beta 1 receptors which speed up depolarisation of SA and AV nodes= -> HR
para cardioinhibitory centre ACh bind to muscarinic receptors which slows depolarisation of SA and AV nodes=

33
Q

hormones and temp affect HR

A

hormones -> HR
-> temp -> HR
plasma electrolytes
-> extracellular Na/ K = extracellular ca= -> HR
age, gender general health, physical fitness

bioscience (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions