Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

biology component 3 > How the heart functions > Flashcards

How the heart functions Flashcards

1
Q

Systole

A

Contraction of the heart chambers

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

Diastole

A

Relaxation of the heart chambers

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

Name for when the atria are conteracted

A

artial systole

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

Sequence of blood being pumped through the heart (systole and diastole)

A

Atrial systole (semi lunar valves closed)
Atrial diastole and ventricular systole ( atrioventicular valves close)
Ventricular diastole

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

Effect of atrial diastole

A

Decreases vol of atria
Increases pressure above that of ventricles
Remaining blood in the atria pushed throught he already open valves

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

Effect of ventricular systole

A

Vol of ventricles decreased
Pressure increases
Blood moves out into the artery down the pressure grad

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

What stops blood flowing backwards into the atria from ventricles down the pressure grad

A

Blood flows collects at pockets in the valves pinching the valves closed in attempt to pass backwards.

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

Based on what gradients do valves prevent back flow of blood

A

Pressure gradients

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

Atrioventricular valves?

A

Prevent back flow of blood from ventricles to atria: Tricuspid and bicuspid

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

Semi lunar valves?

A

Prevents back flow of blood from the arteries to the ventricles: Aortic and pulmonary

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

When do valves open

A

When the pressure above is greater than that in the chamber beneath

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

When do valves close

A

When the pressure in the chamber beneath the valve is greater than in front of it

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

What produces the lub- dum sound perceived as a heart beat

A

The closing of the atrioventricular valves followed by that of the semi lunar valves

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

Function of coronary artery

A

Supplies O2/ blood to the heart muscle

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

Location of coronary arteries

A

2: left and right on the surface of the heart

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

Why do valves on the left of the heart more often become defective

A

Exposed to a higher pressure as left side pumps O2 blood to the whole body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Symptoms of failing valves (leaky)

A

Breathlessness
Fatigue
rapid or irregular heart beat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Location of pacemaker

A

Right atrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Name for peace maker

A

Sino-atrial node

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Characteristics of pacemaker 2

A

Myogenic
Causes heart to beat 55-70 bpm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

myogenic?

A

Heartbeat is initiated from within the muscles and is not dependent on nervous of hormonal stimulation

22
Q

Sequence of electrical impulse by SAN

A

SAN initiates a wave of excitation
Wave spreads over walls of atria causing atrial systole
Excitation is prevented from spreading to ventricles by thin layer of insulating, connective tissue

23
Q

Sequence of electrical impulse from AVN onwards

A

The wave of excitation reaches the AVN and is delayed through this node before it it RELAYED
The wave then travels down the bundle of His
As it reaches the apex of the heart and moves up purkyne fibres, causing ventricular systole
Heart then experiences diastole as the electrical impulse is terminated

24
Q

What causes the termination of the electrical signal following to produce diastole of the heart

A

There is no more conductive tissue after the purkyne fibres

25
Apex of the heart?
Pointed bit: bottom of ventricles
26
Bundle of His?
Highly conductive tissue in the septum
27
What doe AVE stand for and what is it
Atrioventricular node, patch of muscle fibres at the top of the inter ventricular septum
28
Why is the delay of the impulse to the His necessary
To allow the atria to have fully contracted and the ventricles filled before they begin systole
29
Where does the impulse travel after reaching the apex of the heart
Through the purkinje fibres up the sides of the ventricles
30
why does ventricular systole begin from the apex of the heart upwards
to direct blood upwards into the arteries most efficiently
31
Heart rate?
Beats per minute
32
Stroke volume
Vol of blood in cm3 pumped by heart in one beat
33
Cardiac output
Vol of blood pumped by the heart in 1 minute (Stroke vol× heart rate)
34
ECG?
ElectroCardioGram: measures electrical activity of the heart to detect heart problems
35
What structures ensure the heart valves only open in one direction- are not blown open by pressure
Chordae tendineae
36
What does the P wave correlate to
Atrial systole
37
what does the QRS complex correlate to
Depolarisation of the ventricles followed by Ventricular systole
38
what does the T wave correlate to
repolarisation of the ventricles, ventricular diastole
39
Depolarisation meaning
Electrical process that causes systole
40
Fibrillation meaning
Irregular contractions of the cardiac muscles
41
how many times thicker is the left ventricle than the right
3 times
42
What does the diameter of the pressure-volume loop represent
Stroke volume
43
What does volume describe on the pressure- volume graph
Volume of BLOOD in the left ventricle
44
What are the three important graphs
Pressure-time graph Pressure-volume graph (LV) Blood pressure-flow graph
45
Key things to remember when reading graph of pressures in heart
Atrioventricular valves open when pressure in atria is greater than in ventricle and close in the opposite situation Semi lunar valves open when pressure in ventricle is greater than in aorta/pulmonary artery
46
Diasotolic filling?
Passive filling of the atria/ ventricles between T wave and P wave via venous return
47
Why do the atria have less muscular tissue and weaker systole than the ventricles
They pump blood into the ventricles which is a far shorter distance than around the when body as the LV does
48
PR interval?
Time between start of P wave and start of QRS complex, time taken for excitation to spread from atria to ventricles through AVN
49
ST segment on ECG
End of S wave to beginning of T wave
50
What is the name for the line between the T and P wave of the next cycle and what is it
The isoelectric line, it is the baseline of the ECG trace
51
Heartbeat
complete contraction and relaxation of the whole heart
52
Function of the chordae tendinae
Prevent inversion of valves during high pressure created by systole

biology component 3 (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions