Heart

Question 1

What’s ischemia

Answer 1

Insufficient blood flow to supply the heart

Question 2

What’s atherosclerosis?

Answer 2

Thickening of coronary arteries

Question 3

What are the causation for Myocardial infraction

Answer 3

1- atherosclerosis
2- thrombosis blood clot
3- drug
4- surgery

Question 4

What’s the treatment called for heart attack?

Answer 4

Balloon angioplasty and stents

• dye shows blockage in coronary arteries
• guide wire inflated to allow insertion of wire stent
• pump up stent
• unblock vessel

Question 5

What’s the symptoms for meningitis

Answer 5

Seizure, loss of consciousness

Question 6

What causes meningtis

Answer 6

Bacterial infection in CSF, cause increasing pressure in the brain

Question 7

What cell generate CSF?

Answer 7

Specialised epithelial cells -choroid plexus

Question 8

How does CSF get into vein in the brain?

Answer 8

Passive Diffusion through valves on top of brain called arachnoid villus

Question 9

Whats Bbb consist of?

Answer 9

Epithelial cells with right junctions

Question 10

What substances are less permeable to BBB than other … substance ?

Answer 10

Protein and drugs
Less permeable to Bbb
Than lipophilic molecules like alcohol and anaesthetics

Question 11

What causes stroke?

Answer 11

Loss of blood supply to brain, death of neurones

Question 12

Does brain store glycogen?

Answer 12

No, need constant supply of glucose and oxygen

Question 13

Describe the composition of fluid compartment

Answer 13

Total 42L
Intracellular =28L
Extracellular =14L (interstitial 11L, plasma 3L)

Question 14

One osmole (osm) is?

Answer 14

1 osm= 1 mole (6.02 x 10^23) of solute particles in 1L os solution

Question 15

Osmolarity is independent of

Answer 15

MW

Question 16

What molecule can cross a selectively permeable membrane (Ie a cellular membrane)?

Answer 16

Only permeable to water

Impermeable to solutes (ions) such as na, k, cl

Question 17

Define osmotic pressure

Answer 17

Pressure required to prevent osmosis

Question 18

What is heart sound caused by?

Answer 18

The closure of heart valves

Question 19

What’s the first sound and second sound of heart cause by?

Answer 19

First- closure of AV valves ‘lub’
Onset of systole (contraction)

Second- closure of pulmonary, aortic semilunar valves ‘dub’
Onset of diastole (relaxation)

Question 20

What are the three factors that regulate stroke volume?

Answer 20

1. Filling pressure
2. Contractility -sympathetic nerves, circulating hormones
3. Arterial pressure opposing ejection

Question 21

What factors affect the filling pressure (CVP) therefore the EDV? (Pre load)

Answer 21

The end diastolic ventricular volume (EDV)
GBRSCS : Gravity (reduce CVP), blood volume (dehydration- reduce CVP), respiration (ins- increase, ex- reduce), sympathetic nerves - contraction of central and peripheral veins (increase CVP), skeletal muscle pumping -blood squeezed back to heart (increase CVP)

Question 22

Define the frank starling mechanism

Answer 22

Ventricles contract with greater force (Ie stroke volume) if it contains more blood (ie EDV)

Question 23

How does the F-S mechanism maintains the balance bw E and L heart (prevent lung blood from accumulating)

Answer 23

Increase in venous blood return to R ventricle then increase contraction
More blood to lungs
Increase in venous blood return to L ventricle then increase contraction
Increase stroke volume
Blood doesn’t accumulate in lungs

Question 24

What are the characteristics and effects of sympathetic nerve?

Answer 24

Sym– GIW: via sympathetic ganglion, increase HR, stimulates the WHOLE heart.
– release NA, beta 1 adrenergic receptor on SAN, increase Na/ Ca influx, increase rate of depolarisation, increase HR (tachycardia)

Question 25

What type of AR is in the arteriole?

Answer 25

Alpha 1

Question 26

What are the 3 causes of hypotension?

Answer 26

Hypotension= reduction in arterial pressure 1. Loss of blood (heamorrhage) 2. Loss of salt (burns, sweat, diarrhoea, committing) 3. Stree/ emotion (fairing)

Question 27

Describe standing up affects on BP | And how CVS compensate

Answer 27

Standing -effects of gravity leads to blood pooling in legs - reduced BV, lowering CVP - reduced venous return, reduced EDV pressure - reduced stroke volume - reduced BP Baroreceptor reflex compensate -increase BP by reducing nerve firing -release of A

Question 28

Sympathetic nerves release NA/A which bind to alpha 1, beta 1, beta 2 receptors, what are their functions?

Answer 28

Alpha 1 : arteriole constriction Beta 1: vein construction--> frank starling mechanism Beta 2: skeletal muscle vessel dilation

Question 29

What's osmotic pressure and what does it in direct proportional to?

Answer 29

Pressure required to prevent osmosis | Proportional to solute conc

Question 30

What's the purpose of osmosis between cell and interstitial fluid?

Answer 30

Determine the water distribution ie the size of the intra extra cellular compartments

Question 31

Capillary membrane is semi permeable, what does it mean?

Answer 31

Permits diffusion of ions water oxygen nutrient and waste | NOT protein

Question 32

What's the hydrostatic pressure at arteriolar and venous end of capillary?

Answer 32

35mmHg | 15mmHg

Question 33

What are the 2 major roles of lymphatic system

Answer 33

1- drainage (from tissue to CVS) | 2- immune response

Question 34

Describe the process of drainage in lymph system

Answer 34

Fluid (8L/day) from blood to ISF EX fluid passes to lymph capillaries - lymph node -lymph vessel -neck (thoracic duct to subclavian corn) Collects fats from liver and SI deposits it into veins

Question 35

What feature of lymph vessel helps in dranage?

Answer 35

Valves Smooth muscle spontaneous contraction due pacemaker cells Breathing

Question 36

Describe the process of immune response by lymph system

Answer 36

Lymph fluid contains WBCs : Lymphocytes, macrophages, dendritic cells. Detect ANTIGENS from passing fluid Recognised by B-lymphocytes in lymph nodes Activation of immunity B Cells and other immune cells in lymph node produce ANTIBODIES

Question 37

What are the major vessels to heart (artery and veins

Answer 37

Arteries : aorta, carotid, radial, brachial | Veins: vena cava, jugular

Question 38

Exchange occurs through BBB via?

Answer 38

Diffusion down gradient | Facilitated by slow movement of blood and large SA