BIOL125 - The heart and CV

?
  • Created by: Katherine
  • Created on: 19-05-16 14:13
What are the components of the cardiovascular system?
Blood, blood vessels and heart
1 of 144
What are the components of blood?
Erythrocytes, Leukocytes, Platelets, Plasma
2 of 144
What are the components of blood vessels?
Arteries, arterioles, capillaries, venules and veins
3 of 144
What does blood do?
Blood carries oxygen around the body and carries carbon dioxide,
4 of 144
White blood cells are components of what?
Of the immune system
5 of 144
Plasma is what?
It is a soluble component of the blood and contains numerous lipids and proteins
6 of 144
How is serum different to plasma?
If you collect plasma is containngs all the clotting compoenents of the cell. Serum has lost all the clotting components
7 of 144
What are the blood groups?
A, B, AB and O.
8 of 144
What is responsible for the ABO groups?
Two antigens and two antibodies
9 of 144
Who discovered the blood groups?
Karl Landsteiner in 1900
10 of 144
Are antibodies to self or non self antigens naturally present in the blood?
Antibodies to non self are naturally present in the blood.
11 of 144
How can ABO type blood be determined?
Using anti A and anti B antibodies - whether or not agglutination occurs indicates ABO type
12 of 144
If blood is agglutinated by anti A but not by anti B antibodies, what is the blood type?
It is blood type A, as only Antigen A is present
13 of 144
What determines the four blood groups?
It is the combination of the alleles
14 of 144
What antigen will people with blood type A have on the surface of their red cells?
The A antigen
15 of 144
What antibodies will they produce?
They will produced anti-B antibodies
16 of 144
If blood type B is transfused into the system of a blood type A, what will happen?
Their anti- B antibodies will recognised it as foreign and agglutinate the introduced red cells - it can result in death
17 of 144
What type of antigens do blood type O produce?
The do not produce ABO antigens.
18 of 144
What does this mean?
It means that their blood will not be rejected when it is given to others.
19 of 144
What is the catch with blood type O?
While they are universal donors for transfusions, they can only receive blood type O themselves.
20 of 144
What antibodies do people with type AB blood make?
They make none
21 of 144
What does this mean?
It means that AB blood types are universal receivers for transfusions, but their blood cannot be donated because they produce both antigens
22 of 144
What is the path of blood flow?
Deoxygenated blood enters RA from body, blood enters RA -> RV. Blood enters pulmonary artery, oxygenation of blood in lungs, blood enters LA -> Lv, via pulmonary veins. Oxygenated blood pumped frrom LV to aorta. Oxygen leaves blood and enters tissues
23 of 144
What is the structure of the arteries?
They have a large diameter with thick, elastic walls.
24 of 144
How are arteries suited to their function?
They have to withstand high pressure when the ventricles contract - they are supported by the connective tissues and have thick wall, that can expand when the walls contract. They act as a pressure reservouir. They are supported by connective tissue.
25 of 144
What is the structure of the veins?
Large diameter, wide lumen, thin walls and one way valves
26 of 144
How are the veins suited to their function?
They don't have to withstand a high pressure, but they have valves which act to push the blood in to the direction towards the heart.
27 of 144
Can the smooth muscle contract?
Yes - they contract to move blood to different parts of the body by contraction and relaxation of the muscular walls of the arterioles. The capillaries recombine into the venules.
28 of 144
How many chambers does the heart have?
4
29 of 144
What does the right side of the heart do?
It pumps blood to the lungs
30 of 144
What does the left side of the heart do?
It pumps blood to the body
31 of 144
Which side of the heart has a higher pressure?
The left side of the heart is thicker than the right side of the heart.
32 of 144
What is the proper name for the heart strings?
Chordae tendineae
33 of 144
When do these chordae tendineae contract?
They contract when the capillary muscles contract.
34 of 144
What is the function of the chordae tendineae?
They stop the heart from prolapsing, ensuring that the valves seal properly.
35 of 144
What are the different heart valves?
The atrioventricular valves and the semilunar valves.
36 of 144
What are the atrioventricular valves and what do they do?
They separate atria from ventricles and are the bicuspid valve and the tricuspid valve (supported by chordae tendineae and papillary muscles.
37 of 144
What are the semilunar valves and what do they do?
They separate ventricles from arteries and are the pulmonary valve and the aortic valve.
38 of 144
When one set of valves is closed, what is the other one?
Open
39 of 144
What is the brief period in which all 4 valves are closed called?
The isovolumetric period. During this period blood cannot leave or enter the heart.
40 of 144
What is the cardiac cycle?
Events associated with blood flow through the heart in one complete beat
41 of 144
What does the cardiac cycle encompass?
The pump cycle, valve opening and closure, pressure changes, volume changes and heart sounds.
42 of 144
What is systole?
It is ventricular contraction - ejection
43 of 144
What is diastole?
It is ventricular relaxation - filling
44 of 144
What happens in mid to late diastole?
Venous return, ventricles fill and, in late phase, atria contract
45 of 144
What happens in early systole?
Ventricles contract, AV valves close= isovolumetric contraction
46 of 144
What happens in mid to late systole?
Ventricular ejection through open semilunar valves
47 of 144
What happens in early diastole?
Semilunar valves close = isovolumetric relaxation
48 of 144
Do you push all the blood out of the ventricles?
No, no matter how much you push (contract) - this is important in regulaing blood flow
49 of 144
What does the lub sound describe?
S1
50 of 144
What does the dub sound describe?
S2
51 of 144
The sound is produced by...
Turbulant flow of blood against the closed AV and then semilunar valves. It is the sound of the blood against the valves when they close.
52 of 144
What is the End diastolic volume?
It is the maximum ventricular volume
53 of 144
What is the end systolic volume?
It is the minimum ventricular volume?
54 of 144
What is the stroke volume?
It is the maximum ventricular volume - the minimume ventricular volume
55 of 144
What is the description of stroke volume?
Amount of blood ejected/ beat
56 of 144
What is the minium blood pressure?
It is the diastolic pressure (DP)
57 of 144
When does the SP rise?
When the aortic valves open
58 of 144
How do you calculate the pulse pressure?
SP - DP
59 of 144
When measuring blood pressure, when can you hear the systolic pressure?
When the pressure decreases. You can continuously release the pressure until you get down to the disastolic pressure
60 of 144
What is the normal blood pressure?
120/80mm
61 of 144
What is the blood pressure of someone with hypertension?
140-159/90-99mm
62 of 144
What is the blood pressure of someone with severe hypertension ?
>159/>99mm
63 of 144
What is hypertension associated with?
It is associated with obesity, high cholesterol, smoking, genetic predisposition. It is also associated with atherosclerosis (build up of fatty deposits in walls of arteris) which narrow the lumen.
64 of 144
With increasing age, what happesn to systolic pressure?
It begins to increase, due to reduced elasticity and hardening of the walls.
65 of 144
What type of muscle is the skeletal muscle?
Neurogenic
66 of 144
The heart does not need input from CNS to contract, this means that it is...
Myogenic
67 of 144
The heart generates these signals on a periodic basis due to its own ....
Autohythmicity
68 of 144
The heart is made up of
myocardial cells (contracticle muscle) and pacemaker cells ( not contractile, generate electrical impusles)
69 of 144
Where are pacemaker cells concentrated?
They are concentrated in two regions of the myocardium called the sinoatrial node and the atrioventricular node.
70 of 144
Heart contraction is driven by the...
SA node
71 of 144
What spreads these electrical signals throughout the heart muscle?
Confuction fibres.
72 of 144
What is the conductino system?
Signla passes from the SA down to the AV node, slight delat of about 0.1 of a second. Pass to the bundle of his. Pass along the purkinje fibers.
73 of 144
How does the spread of excitation occur?
Interatrial pathway, Internaodal pathway, AV node transmission
74 of 144
What is the interatrial pathway?
SA node -> rightatrium -> left atrium = it is rapid and involves simultaneous contraction of right and left atria.
75 of 144
What is the internodal pathway?
SA -> AV node
76 of 144
What is AV node transmission?
Only pathway from atria to ventricles. Slow conduction - AV nodal delay = 0.1 sec. Atria contract before ventricles.
77 of 144
What is the first phase of action potentals?
Influx of sodium ions and you get a depolarisation of the nerve cells. At the peak you get repolarisation as the potassium channels open and you get an efflux of potassium ions.
78 of 144
What is phase 2?
It is an efflux of potassium ions as the potassium channels open.
79 of 144
What is phase 3?
You get back to resting potential
80 of 144
What is the order of action potentials?
Rapid depolarisation, action potential, repolarisation.
81 of 144
What does the generation of pacemaker potentials involve?
It involved the movement of Na+, K+ and Ca 2+ ions. Concentration of these ions is similar to other cells.
82 of 144
What is the slow depolariseation due to?
It is due to funny channels that control the movement of Ka+ and Na+ ions.
83 of 144
The cardiac action potential is mainly due to the movement of...
Ca2+ ions.
84 of 144
Slow depolarisation is caused by...
K+ channels close, funny channels open, slower efflux of K+, influx of Na+
85 of 144
What happens just before the threshold?
Ca2+ channels open, slow influx of Ca2+
86 of 144
What happens at the threshold?
Rapid Ca2+ influx
87 of 144
What happens at repolarisation?
Ca2+ influx decreases, K+ efflux increases
88 of 144
How often does slow depolarisation occur a day?
Around 100,000 times
89 of 144
What is cardiac output?
It is the volume of blood pumped out of each ventricle in one minute (same for both ventricles)
90 of 144
How is cardiac output determined?
CO = HR X SV
91 of 144
If you stimulate the sympathetic nervous system, what happens?
You get increase output of blood from the heart
92 of 144
If you stimulate the parasympathetic nervous system, what happens?
You get decreased output of blood from the heart
93 of 144
Adrenaline has a similar role to which?
To the sympathetic input
94 of 144
Stroke volume is affected by?
Ventrcular contractility, end diastolic volume and afterload
95 of 144
What is ventricular contractility?
It is controlled by sympathetic input which gives increased force.
96 of 144
What is end diastolic volume ?
It is the volume of blood in the heart at the end of diastole, it afftects the degre of strenching of the cardiac muscle.
97 of 144
What is the afterload?
It is the back pressure in the arteries
98 of 144
What is starling's law of the heart?
When the rate at which blood flows into the heart from the veins changes, the heart automatically djusts its output to match the inflow.
99 of 144
What happens if an increase in end diastolic volume occurs?
The force of ventricular contraction rises, producing an inrease in stroke volume and cardiac output.
100 of 144
Stretching of muscle fibres does what to contraction force?
It increase it
101 of 144
As EVD increases, what happens to SV?
It increases to compensate, so no pooling occurs.
102 of 144
What is a test used to look for clinical abnormalities in the conduction of electrical activity of the heart?
An ECG - Electrocardiogram
103 of 144
Is it invasive?
No, exxternal measure of hearts electrical impulse
104 of 144
What are the components of a standard ECG trace?
P, PQ segment, QRS complex, QT segment, T wave, TQ interval
105 of 144
What is the P wave?
it is atrial depolarization
106 of 144
What is the PQ segment?
AV nodal delay
107 of 144
What is the QRS complex?
Ventricular depolarization
108 of 144
What is the QT segment?
Ventricular systole
109 of 144
What is the T wave?
Ventricular repolarization
110 of 144
What is the TQ interval?
Ventricular diasole
111 of 144
What is it called when your heart rate is fast?
Tachycardia
112 of 144
What is it called when your heart rate is slow?
Bradycardia
113 of 144
What is heart block?
It is slowed/ diminished conduction through AV node which occurs in varying degrees.
114 of 144
What is ventricular fibrillation?
Loss of co-ordination of synchronised electrical activity of the heart
115 of 144
How can this be fixed?
You must quickly defibrillate the ventricular muscle by passing a large current through the chest.
116 of 144
What is pericarditis?
It is inflammation of pericardium, caused by accumulation of blood/pus/fluid in pericardical space
117 of 144
What causes pericarditis?
Trauma, infections, tumours
118 of 144
What are the symptoms of it?
Chest pain, difficulty breathing, fatigue.
119 of 144
What is the effect of pericarditus on the function of the heart?
It can induce compresion of the heart, resulting in reduced end diastolic volume.
120 of 144
What are some disorders of heart valves?
Rheumatic fever, mitral valve prolapse, aortic regurgitation
121 of 144
What is Rheumatic fever?
Inflammation of the cardiac valves - it slows blood from heart chambers
122 of 144
What is mitral valve prolapse?
Leaky mitral (bicuspid) valve - reduced ejection fraction
123 of 144
What is aortic regurgitation?
Leaky aortic semilunar valve - causes volume overload in LV, LV increases contraction to compensate
124 of 144
What are the symptoms of Mitral valve prolapse?
Between age 20-30. Pain fatigue, palpitations, dizziness, shortness of breath
125 of 144
What is coronary heart disease caused by?
By thrombosis and embolism, resulting in reduced blood flow to myocardium and blockage of coronary artery
126 of 144
What is myocardial infarcation
Heart attack = tissue death
127 of 144
What is congestive heart failure?
Weak heart leads to reduced blood circulation due to coronary artery disease, myocardial infarction and infection. Pumping pressure to systemic circulation decreases. Increased end diastolic volume.
128 of 144
What are drugs commonly used in heart disease?
Digitalis, Statins, ACE, Angiotensin II receptor antagonists.
129 of 144
What is Digitalis, and what does it do?
It makes the heart contract harder and is used when the hearts pumping function has been weakened; it also slows some fast heart rhythms (tachycardia)
130 of 144
What are statins?
Blood cholesterol lowering agents.
131 of 144
What are ACE inhibitors?
They stop production of angiotensin II, a hormone that constricts blood vessels, and so is used to control high blood pressure. Also used for persons with heart failure, where there the heart is unable to pump enough blood to supply the body's needs.
132 of 144
What are angiotensin II receptor antagonists?
They work on the same system as ACE inhibitors and prevent the hormone angiotensin II from acting on cells.
133 of 144
How does digitalis work?
It is a potent inhibitor of the sodium potassium pump and so causes intraceullular Na+ to increase. It leads to accumulation of intracellular Ca2+ via a Na+/Ca2+ exchange system. Increased contractility of heart muscle via interaction Ca2+ & troponin
134 of 144
What are more drugs used to treat heart disease?
Beta blockers, Nitroglycerine and amyl nitrite, Calcium channel blockers, Thrombolytic agents, aspirin.
135 of 144
What do beta blockers do?
Slow the heart and make it beat with less contracting force, so blood pressure drops. Used for high blood pressure; angina; to prevent repeat heart attacks.
136 of 144
What are Nitroglycerine and amyl nitrite?
They dilate coronary arteries and stop chest pain in angina
137 of 144
What do calcium channel blockers do?
Dilate blood vessels. Used fro high blood pressure and chest pain. Can slow the heart
138 of 144
What do thrombolytic agents do?
They are given during or immediately after a heart attack to break up a blood clot in the cornonary artery in order to restore blood flow.
139 of 144
What does aspirin do?
Lowers risk of a heart attack in at risk individuals. Also helps to keep arteries open in those who have had a previous heart by pass or other artery opening procedure.
140 of 144
How do Beta blockers work?
They bind to B adrenergic receptors located in cardiac tissue and inhibit the binding of noradrenaline and adrenaline to these receptors.
141 of 144
How do beta blockers work? Contiuned
They reduce sympathetic influences that normally stimulate heart rate and contractility and so they cause a decrease in these activities. Slows the heart rate, increases delat at the AV node, decreases action potential frequency at SA node,
142 of 144
How else do they work?
They decrease contracile force of caridac muscle. Lowers blood pressure
143 of 144
Some beta blockers are partial antagonists meaning that..
They provide some background of sympathetic activity while preventing enhanced sympathetic activity.
144 of 144

Other cards in this set

Card 2

Front

What are the components of blood?

Back

Erythrocytes, Leukocytes, Platelets, Plasma

Card 3

Front

What are the components of blood vessels?

Back

Preview of the front of card 3

Card 4

Front

What does blood do?

Back

Preview of the front of card 4

Card 5

Front

White blood cells are components of what?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Physiology resources »