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PRINCIPLES OF CELLULAR FUNCTION. 1. Regarding CSF (page 612) a. Production 50 – 100ml /day - volume 150ml, production 550ml/day b. Drained through choroids plexus - 50-70% formed in choroids plexuses, drained in arachnoid villi c. Greater protein content than blood - no, much less d. Content essentially same as brain ECF - yes 2. Regarding body fluid composition, which is approximately 40% of bodyweight a. ICF - yes b. ECF - 20% (includes interstitial and plasma volume) c. TBW - 60% d. plasma - 5% 3. Which penetrates CSF fastest a. H2O, CO2, O2 b. Na, K, Cl - via Na-K-2Cl cotransporter c. N2O - possibly this d. HCO3 - slow 4. The main buffer in the interstitium is a. protein - blood and intracellular b. haemaglobin -blood c. phosphate - intracellular d. ammonia - urine e. HCO3 - THIS ONE interstitial and blood 5. Which of the following is 20% of total body weight a. ECF - this one b. ICF - 40% c. TBW - 60% d. Blood volume - 5%

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Page 1: PRINCIPLES OF CELLULAR FUNCTION

PRINCIPLES OF CELLULAR FUNCTION. 1. Regarding CSF (page 612)

a. Production 50 – 100ml /day - volume 150ml, production 550ml/dayb. Drained through choroids plexus - 50-70% formed in choroids plexuses, drained in arachnoid villic. Greater protein content than blood - no, much lessd. Content essentially same as brain ECF - yes

2. Regarding body fluid composition, which is approximately 40% of bodyweight a. ICF - yesb. ECF - 20% (includes interstitial and plasma volume)c. TBW - 60%d. plasma - 5%

3. Which penetrates CSF fastest a. H2O, CO2, O2 b. Na, K, Cl - via Na-K-2Cl cotransporterc. N2O - possibly thisd. HCO3 - slow

4. The main buffer in the interstitium is a. protein - blood and intracellularb. haemaglobin -bloodc. phosphate - intracellulard. ammonia - urinee. HCO3 - THIS ONE interstitial and blood

5. Which of the following is 20% of total body weight a. ECF - this oneb. ICF - 40%c. TBW - 60%d. Blood volume - 5%

6. Regarding the function of the smooth endoplasmic reticulum; which is incorrect a. steroid synthesis b. drug detoxification / cytochrome P450 c. protein synthesis - rough ERd. role in carbohydrate metabolism -

7. Regarding ICF; which is incorrect a. Na+ of 135 - this one, [Na] around 10mmolb. K+ of 140 c. Mg2+ of 58 d. Ca2+ of 0.0001 e. PO4- of 75

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8. In which component does a solution of 5% dextrose dissolve a. ECF b. ICF - mostly this one (2/3)c. Interstitial fluid d. Intravascular e. Transcellular

9. The concentration of ICF vs ECF a. lower Mg++ - higher intracellular, also higher K, lower Na, HCO3, Clb. higher PO4— - yes

10.Regarding the composition of CSF a. production is 50-100 mls per day no, production about 550mL/dayb. has the same composition as cerebral ECF yesc. higher conc. of K+ with respect to plasma no, about halfd. higher concentration of protein no, almost no protein

11.Regarding CSF a. Composition is esentially the same as brain ECF trueb. CSF production is ~150mls per day false

12.1 litre 5% dextrose given intravenously distrubutes predominantly to: -throughout TBW, 2/3 ICFa. Intracellular compartment - yesb. Interstitial compartment c. Extracellular compartment d. Intravascular compartment e. Transcellular fluid

13.The main buffer in the interstium is a. Protein b. Haemoglobin c. Phosphate d. Ammonia e. HCO3 - this one

14.Total body water ???a. increases with age - decreases slightlyb. is typically 45% of bodyweight - 60%c. is typically 63 % of body weight - trued. is greater in men than women - truee. is composed largely of interstitial fluid - no intracellular

15.With the addition of 1 litre of 5% dextrose intravenously to which compartment is it mainly distributed a. intracellular -disunb. interstitial c. extracellular d. transcellular e. vascular

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16.Regarding the composition of ECF versus ICF . ECF has a. decreased magnesium - yes, 2 vs ~25b. increased phosphate - 2 vs 100c. increased potassium - 5 vs 140d. decreased sodium - 140 vs 10

17.ECF compared to ICF has a. increased potassium - nob. decreased phosphate - yesc. increased phosphate - nod. decreased sodium - no

18.A fit healthy 20 y/o male lose 1 litre of blood a. the haematocrit falls immediately - no it dontb. this is a 35 % blood loss - 30%c. plasma protein synthesis is not increased - suspect it is

19.Anion gap is a. Sodium + potassium – bicarbonate - Na + K – Cl – HCO3b. due to organic protein ions and phosphate ions - probablyc. increased in hyperchloremic metabolic alkalosis - probably acidosis in question – normal anion gap

20.Ratio of HCO3- ions to carbonic acid at pH of 7.1 is a. 1 - pH 6b. 10 - this onec. 0.1 - very very acidicd. 100 - very very alkalinice. 0.01 - uber acidic

21.With the loss of 1 litre of blood a. haematocrit falls immediately - nob. iron resorption is not increased - surely it isc. this equals 35 % plasma volume loss - 30% (total 3.5litres)d. baroreceptors increase parasympathetic output - decrease parasympathetic firing, increase sympathetic firinge. red cell mass normalises within 2 weeks - 4-8weeks

22.What is the hydrogen ion concentration at a pH of 7.4 a. 0.0001meq/L - 7.0b. 0.00004 meq/L - this onec. 0.0004 meq/L - <7.0d. 0.0002 meq/L - <7.0e. 0.00002 meq/L - 7.7

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23.Regarding basic physiological measures all of the following are true EXCEPT a. osmolarity is the number of osmoles per litre of solution - true (osmolality osmoles per kg of solvent)b. pH is the log to the base 10 of the reciprocal of hydrogen ion concentration - truec. carbon has a molecular mass of 12 dalton - true (Dalton = atomic mass unit)d. osmolarity is measured by freezing point depression - ??osmolalitye. one equivalent of Na+ is 23g/L - 23g, not 23g/l

24.ECF compared with ICF has a. A higher K+ concentration - nob. A lower PO4 2- concentration - yesc. A higher Mg++ concentration - nod. A lower NA concentration - no

25.Regarding CSF a. composition is the same as brain CSF means ECF i think.b. CSF production is 50-100 mL/day no, 550mL/dayc. The protein content of CSF is higher than plasma nod. The K+ concentration in CSF is greater than in plasma no

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NERVES AND MUSCLES 1. EPSP is different to AP in that:

a. Propagated – depends on summation and level of inhibition - ipspsb. All or none - EPSPs are not all or none – is proportionate to strength of afferent stimulus.c. Something about overshoot ???d. None of the above

2. Most important ion for cardiac RMP a. Na – (NO) external sodium affects magnitude of cardiac action potential b. Ca – (NO) although shutting Ca channels is part of final repolarisation (with K efflux)c. K – YES – actively pumped out of cell to maintain resting membrane potential – p78d. Cl -not mentioned in phys book?

3. Calmodulin is involved in a. Smooth muscle relaxation b. Smooth muscle contraction YES – calmodulin dependent light chain kinase… binds calcium to allow contractionc. Skeletal muscle contraction - Ca binds to troponin C to activate itd. Skeletal muscle relaxation

4. Regarding resting membrane potential a. Hyperkalemia makes the membrane potential more negative yes, as outside would be relatively more positive.b. Amplitude of the action potential is dependent on Na permeability no – dependent on external Na concentration.c. Increased K permeability makes resting potential more positive yes, with more K in cell, RMP would be less

negative = more positive…? What is permeability?

5. Regarding velocity of conduction of nerves, a. Velocity is proportionate with diameter does increase. ? proportionate?b. Some C type nerves may be myelinated NOc. With local anasthetic sensory nerves are always affected before motor nerves no – depends on where in the nerve

they are… outside ones will be affected first, may not necessarily be sensory fibres first.

6. Bradykinin a. name is derived from its action eg. It decreases heart rate falseb. contracts visceral muscle yes “causes contraction of non-vascular smooth muscle”c. contracts smooth vascular muscle - no – causes vasodilationd. is not related with pain and pain sensation false. Is related to pain sensation.

7. Smooth muscle; underlying oscillatory depolarisations are due to a. Ca influx calcium is certainly the cause of depolarization.. don’t know if it is also responsible for this?b. K influx c. Cl influx d. Na influx e. Na efflux

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8. Regarding smooth muscle contraction; calmodulin a. causes smooth muscle contraction yes, it is part of the mechanism of contraction – when bound by calcium.b. causes smooth muscle relaxation no, myosin light chain phosphatase.c. sustains contraction in smooth muscle no - latch bridge

9. Nerve fibre types; which is correct a. Gamma is to motor muscle spindles TRUEb. Beta is to motor muscle spindles Touch, pressure, motorc. Alpha is to motor muscle spindles proprioception, somatic motor.

10.Nerve fibres a. increasing the diameter increases the conduction velocity yes

11.Regarding cardiac muscle a. there are no Z bands false these are where intercalated discs attach at each end of muscle fibreb. resembles skeletal truec. intercalated discs are loosely attached false, strong to allow transmission of force with contraction.d. gap junctions resist the flow of ions no, allow conduction of electrical impulses to enable synchronized

depolarization.

12.Smooth muscle contraction is due to a. Na+ influx b. Ca++ influx - true. Calcium binds to calmodulin, causing it to bind myosin and cause contraction of muscle.c. Cl- efflux d. Na+ efflux e. Cl- infux

13.Calmodulin is involved in a. smooth muscle contraction trueb. smooth muscle relaxation c. myocardial contractility

14.With respect to the cardiac action potential a. The plateau of repolarisation phase may be up to 200 times longer than the depolarisation phase. True.

Depolarization = 2mS, repolarisation = 200mS or more.b. Unlike the nerve action potential there is no overshoot no, overshoot is also present in cardiac muscle.

15..In contracting skeletal muscle a. The H zone increases no, it decreases – it is the distance between adjacent actin filamentsb. The I zone decreases correct – as myosin gets closer to z line, I zone is squashed.c. The A zone increases no – it is the length of the myosin filaments, and therefore unchanged.

16.With regards to membrane potential a. the Donan effect relies on non-diffusable ions Yesb. the exterior of the cell is negative with respect to the interior no - c. the membrane potential tends to push chloride ions out of the cell ?? Cl ions diffuse into cell down conc gradient,

electrical gradient pushes Cl outd. potassium leaks out against a concentration gradient - no pumped out against conc gradiente. it can be derived by measuring the chloride concentration and using the Nernst equation - yes

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17.Na+/K+ ATPase a. hydrolyses ADP to ATP no – other way aroundb. extrudes 3 Na+ from the cell for every 2 K+ in Truec. consists of an alpha, beta and gamma sub-unit only has alpha and beta subunits.d. lies on the ECF side of the membrane spans whole membranee. is potentiated by the drug ouabain inhibited by ouabain and digitalis etc glycosides.

18.With regard to the action potential of a neuron with an RMP of –70mV a. the firing level is likely to be-30mV no – likely to be -55mVb. the overshoot will not extend much past 0mV no, likely to extend to +35mVc. the absolute refractory period occupies only 10% of repolarisation no, about 1 third of the total repolarisation

periodd. chloride influx will restore the membrane potential no – potassium efflux.e. increasing the external chloride ion concentration increases the RMP who knows

19.In skeletal muscle a. the immediate energy source for contracting is GTP no, ATPb. troponin T inhibits the interaction with myosin no, that’s troponin Ic. the myosin is contained entirely within the A band yesd. the heads of actin contain the ATP hydrolysis site no, this is on the myosin heads.e. tropomysin is made up of 3 sub-units troponin is 3 parts, tropomyosin is dimer

20.In smooth muscle the alternating sinusoidal RMP is due to a. calcium influx Trueb. sodium influx c. potassium influx d. chloride influx e. potassium efflux

21.The special feature of the contraction of smooth muscle is that a. actin is not involved b. myosin is not involved c. calcium is not involved d. ATP is not the energy source e. The membrane potential is unstable has to be this one.

22.With respect to the cardiac action potential a. unlike nerve action potential there is no overshoot - there is overshoot +20mVb. plateau and repolarisation may be 200 times larger than depolarisation phase - 100x longerc. the resting membrane potential is –90mV - yesd. sodium channels are progressively inactivated in phase 2 - suddenly closed in Phase 1e. it is usually 20 ms in duration - no, 200ms +

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23.Upon stretching intestinal smooth muscle a. it hyperpolarises b. the tension is due to elastic forces only c. it depolarises - trued. relaxation occurs e. it is an example of a multi-unit smooth muscle

24.Upon skeletal muscle contraction a. the H zone increases - decreases – distance between actin filamentsb. the I zone decreases - yesc. the A zone decreases - no, length of myosind. the A and I zone increase - I decreases, A is length of myosine. none of the above

25.All of the following are true of skeletal and cardiac muscle EXCEPT a. they both have striations b. they have high resistance gap junctions - this is false – cardiac gap junctions allow easy transmission of

impulses…

26.With respect to smooth muscle, calmodulin a. acts to curtail contraction b. acts to stimulate contraction - yesc. acts to limit relaxation d. acts to stimulate relaxation

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NERVOUS SYSTEM 1. Question about dorsal column + spinothalamic tracts

2. Question about neural connections regarding balance (involving cerebellum and optic tracts)

3. The main inhibitory neurotransmitter of the spinal cord is a. glycine - Yesb. GABA in the brainc. Ach excitatoryd. Dopamine brain (neocortex, hypothalamus), retinae. Substance P endings of primary afferent neurons mediating nociception.

4. Vestibular nerve has direct connections to a. cerebellum Indirect connection b. oculomotor nuclei TRUE has connections to thalamus, 3rd N nucleus, and spinal cordc. cortex Indirect connection via thalamus

5. Which area has the best visual acuity a. fovea centralis TRUEb. optic disc c. area with maximal rods

6. The hypothalamus is essential for a. movement b. visual acuity c. renal function d. none of these, responsible for body temp, circadian rhythms, pituitary stimulation, hunger, thirst…

7. The main inhibitory neurotransmitter of the spinal cord is a. glycine This one.b. GABA c. Ach d. DA e. Substance P

8. The kappa receptor actually I THINK A IS THE RIGHT ONE (variable in books) a. is involved in spinal analgesia b. is responsible for dysphoric reactions and hallucinations true, also meiosis, diuresis, sedation, analgesia.c. is responsible for euphoria, dependence, and analgesia referring to the mu receptors.

9. What does presynaptic inhibition require? a. contact of an inhibitory neurone

10.Which penetrates CSF fastest a. H2O-CO2-O2 b. CO2-O2-N2O this one I think

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11.Which of the following is incorrect a. Pain and temperature travel in the ventral spinothalamic tract – incorrect (lateral)

12.The most visually sensitive part of the eye is the a. Optic disc B;ind spotb. Fovea centralis this onec. Area with maximal rods used for night vision - peripheral

13.The major inhibitory transmitter in the spinal cord is a. Glutamate excitatory in brainb. GABA inhib in cerebellum and brainc. Glycine this oned. Aspartate excitatory visual cortexe. ACh NMJ and PNS

14.The major inhibitory substance of the spinal cord is a. GABA b. Glutamate c. Aspartate d. Glycine e. None of the above

15.The sensation for cold a. is relayed by the thalamus spinothalamic tract (lateral)b. is transmitted by the dorsal columns NO- touch, proprioception, vibrationc. is an uncrossed sensory modality no, crosses at level of dorsal hornd. is mediated by substance P fluxes yese. is mediated by A alpha fibres no A delta fibres

16.Alpha 1 stimulation will lead to a. contraction of bladder trigone and sphincter - trueb. bronchial smooth muscle contraction - no, muscarinic (parasymp) causes contractionc. pupillary constriction – no, parasympd. increased AV conduction – no, betae. skeletal muscle vasodilation – no alpha causes constriction

17.Anterolateral dissection of the spinal cord is associated with loss of a. ipsilateral loss of pain – no, lose contralateral pain, as crosses immediatelyb. ipsilateral loss of temperature – no, lose contralateral temp, as crosses immediatelyc. ipsilateral hyperreflexia must be this one. Reflexes don’t cross. Inhibitory pathway already crossed.d. contralateral vibration loss – no, vibration = dorsal columns, uncrossed.

http://www.bio.psu.edu/people/faculty/strauss/anatomy/nerv/nervous.htm 18.With regards to CSF composition

a. it is similar to the ECF of the brain – yes, essentially the same.

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19.Which of the following have a specific beta effect on smooth muscle contraction a. adrenaline – not specifically betab. noradrenaline - mainly acts on alpha receptorsc. isoprenaline - specific beta, but beta causes relaxation of most smooth muscle…

20.MAO breaks down a. seretonin – yes (MAO-a)b. tryptophan – no, 5-HT isc. glycine - nod. GABA - noe. Glutamate - no

21.In the formation of adrenaline a. COMT produces adrenaline from noradrenaline - nob. Phenylalanine is converted to tyrosine - truec. Seretonin is a vital intermediate step - nod. Dopamine is two noradrenaline molecules side by side - noe. Dopa is formed from dopa decarboxylase – no, dopamine is created from dopa by dopa decarboxylase

22.(True) acetylcholinesterase a. forms acetylcholine from acetate b. is produced by the liver c. functions only in nerve endings d. is involved in GABA metabolism e. none of the above - this one

23.All the following are neurotransmitters EXCEPT a. seretonin FALSEb. glutamate FALSEc. adenosine FALSE d. insulin don’t knowe. glucagon don’t know

24.Inhibitory neurotransmitters increase the post synaptic conductance to a. sodium b. chloride TRUEc. sodium and magnesium d. magnesium e. all of the above

25.Which of the following is true a. contraction of cardiac muscle is about as long as its action potential no, contraction is 1.5 times as long as AP

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26.A subject is injected with a substance that caused : slight increase in HR; no change in BP; did not impair ejaculation; decreased sweating; pupillary dilatation. It was most likely –

a. nicotinic antagonist b. nicotinic agonist c. alpha blocker d. muscarinic antagonist - must be this

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METABOLISM

27.The liver produces all, EXCEPT a. Complement - except factor 4b. Albumin c. Gamma Globulins - this oned. Fibrinogen e. Coagulation factors

2. Vitamin D; which is incorrect a. undergoes 1 hydroxylation in the liver – true, and 25 in the kidney

3. All plasma proteins are synthesised in the liver except a. plasminogen b. albumin - only place albumin is synthesisedc. gammaglobulins - this oned. complement

4. Which is INCORRECT a. muscle utilises fat in strenuous exercise - false – fat at rest and after exerciseb. initially get a rise in BSL secondary to increased gluconeogenesis - no – rises because of hepatic glycogenolysisc. insulin secretion decreases - yesd. initially muscle utilises glycogen stores - yes, and increased GLUT 4 glucose uptake

5. Regarding cholesterol, which is incorrect? a. essential in cell wall synthesis - no – essential part of cell MEMBRANESb. plants have cholesterol but it is not absorbed by humans -plants have sterols, but not absorbed.c. only found in animal cells - yes, mostly from egg yolks and animal fats…

6. Regarding fatty acid metabolism a. Fatty acids are broken down in mitochondria by beta-oxidation - yes (p298)

7. Regarding RQ, which is incorrect a. Average is about 0.82 - correctb. RQ of brain tissue is approximately 1.0 - true, 0.97-0.99c. RQ CHO = 1.0 - yesd. RQ of CHO is greater than that of protein - true, from wiki – protein RQ 0.8-0.9e. RQ of fat is 0.90 - False. 0.7

8. 14. Regarding Ca++ metabolism, which is incorrect a. 1,25 DHCC is formed in the liver b. PTH acts on the distal tubule to decrease phosphate absorption

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9. Which is the largest in size a. Beta 1 globulin b. Fibrinogen – 340kDac. Albumin – 67kDad. Alpha globulin e. Haemoglobin – 68kDa

10.The heat lost by the body at 21 degrees is due to a. sweating b. defecation c. urination d. radiation/conduction

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ENDOCRINOLOGY 1. Regarding thyroid hormone

a. acts on a cell surface receptor - nuclearb. decrease metabolic rate - noc. increase Na/K atp-ase function - yesd. increase affinity beta adrenergic receptor sensitivity, but not receptor number - no – sensitivity and numbere. reduces cholesterol (LDL) receptors - no increases LDL uptake in the liver

2. Regarding thyroid hormones a. They alter proportion of beta myosin heavy chains - increase alpha, decrease beta…b. Increase number but not affinity of beta adrenergic receptors - falsec. Decrease activity of Na/K ATP-ase - no - increased. Increase number of LDL-receptors - true

3. Which of the following does not utilise the same receptor effector action a. insulin – tyrosine kinase Ab. glucagon – cAMPc. PTH – cAMP (+IP3)d. ACTH – cAMPe. All of the above

4. Thyroid hormones; which is correct a. T3 acts at a nuclear receptor

5. Which of the following is not a gastrointestinal hormone a. Secretin – yesb. CCK – yesc. VIP – yesd. GIP – yese. ENP – enteric neural peptide – this one?

6. Parathyroid hormone; which is correct a. causes low PO4 – yesb. released with rises in blood calcium levels – low Cac. blocks vitamin D synthesis – enhances Vit D synthesis

7. Hypothyroidism doesn’t cause a. cretinism – yes, if congenitalb. myxoedema – yesc. early genital development – this oned. hair loss – yes

8. With regard to cortisol, which is incorrect a. It is predominantly metabolised in the liver – yesb. It has a permissive action on vascular reactivity – yes they doc. It has greater mineralocorticoid activity than glucocorticoid activity – wrong

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9. In DKA ketones accumulate because – who knowsa. They are not buffered b. ???/products of glucose metabolism

10.Insulin a. Increases the number of glucose transporters on the cell surface – yesb. Regulates intracellular glucose metabolism – nothing to do with it

11.Regarding thyroid hormones, which is incorrect a. They increase plasma cholesterol – decrease by upregulating LDL receptorsb. They increase the activity of Na-K ATPase – think soc. They increase the number/affinity of Beta adrenergic receptors – they dod. They alter the proportion of alpha myosin heavy chains – they doe. They have a calorigenic action – they do

12.Regarding insulin a. it increases protein catabolism in muscle – no, that is glucagonb. secretion is inhibited by somatostatin – yesc. secretion is stimulated by phenytoin – no inhibitedd. it causes decreased K+ uptake into adipose tissue – increased e. it causes decreased protein synthesis – increased

13.Regarding glucagon a. it is secreted by the pancreatic B cells – A Cellsb. it increases glycogen formation – glycogenolysisc. it has a half life 30 minutes – 5-10minutes, duration 30 moniutesd. secretion is stimulated glucose – inhibitede. it stimulates insulin secretion – yes

14.With regard to thyroid physiology a. T3 and T4 are metabolised in the spleen and bone marrow – don’t think sob. T3 and T4 bind and act at the same cell membrane receptor – no, nuclear receptorsc. T4 is synthesised from tyrosine held in thyroglobulin – yesd. T4 is more active than T3 – T3 > T4e. T3 is bound to a complex polysaccharide in the plasma – TBG, albumin and transthyretin

15.A deficiency of parathyroid hormone is likely to lead to – low calcium, and high phosphate…a. hypophosphatemia – no hyperphosphataemiab. the formation of kidney stones – XS PTH hypercalcaemia and stones, so noc. a self limiting illness – nod. neuromuscular hyperexcitability – yes, low extracellular calcium, leading to tetanye. cystic bone disease – no

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16.With regard to adrenal physiology a. glucacorticoids exert their action by cGMP activation – no, hormone receptorsb. cortisol has negligible mineralocorticoid activity – equally potent as mineralo and glucocorticoidc. the largest steroid molecules are the oestrogens – smallest – 18carbons vs 21carbon pregnanesd. dopamine is secreted by the adrenal medulla – yes, secretes all aminese. the only glucacorticoid secreted in significant amounts is cortisol – no, also corticosterone

17.Insulin secretion is stimulated by all of the following EXCEPT a. mannose – yesb. glucagon – yesc. noradrenaline – this oned. leucine – yese. acetylcholine – yes

18.Insulin a. is secreted by the A cells in the islets of Langerhans – B Cellsb. is a triple helical polypeptide – noc. is synthesised as a prohormone – preprohormone? This one probablyd. binds at cytoplasmic receptor sites – no, membrane based receptorse. causes K+ to leak out of cells – no into cells

19.Which of the following does not utilise the same receptor (effector?) in its mechanism of action a. insulin – TKb. glucagon c. PTH d. ACTH e. They all have the same mechanism of action

20.Glucocorticoid effects; which are incorrect (question may have been slightly different?) a. increased protein catabolism – correctb. increased glucose 6 phosphatase – yesc. increased transamination / deamination of amino acids – probablyd. increased peripheral glucose utilisation – inhibit ite. decreased glycogen synthetase – probably

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DIGESTION & ABSORPTION

1. Regarding amino acid digestion a. Occurs equally fast in all parts of the small intestine – rapid in duo and jej, slow in ileumb. Absorbed with H+/Na+/Cl- – yes

2. Vitamin A, K, D are absorbed in a. stomach b. duodenum c. terminal ileum d. proximal small bowel – this onee. ascending colon

3. Regarding fat digestion and absorbtion, all are correct EXCEPT a. It is largely completed in the duodenum – no falseb. it’s final destination depends on the size of FFA – yesc. Transport is in cholymicrons – yesd. FFA diffuse passively through the brush border – truee. pancreatic dysfunction may lead to steatorrhea – ? to do with pancreas.

4. Low protein diet, normal caloric intake; which effect is incorrect a. increased creatinine – not affectedb. increased urea – negative nitrogen balance – low urea.

5. Absorption of amino acids; which is correct a. cotransported with ions – thisb. L and D isomers are absorbed via different mechanisms c. greatest source is GIT mucosa

6. Fat digestion; which is incorrect a. most occurs in the ileum – thisb. colipase is needed to allow lipase to work c. lipase is in the stomach, but has no real role

7. Where does vitamin A, D and K absorption occur a. proximal small bowel – disunb. stomach c. terminal ileum d. dueodenum e. ascending colon

8. With regard to fat metabolism a. micelles are formed in the brush border – not this oneb. colipase is required for metabolism – possibly

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9. Iron absorption a. is increased by Vit C – yes it isb. is constant regardless of need – no, changes with erythropoeisis etcc. occurs in the proximal small bowel – yes, duodenumd. requires intrinsic factor – that’s B12

10.With regard to protein digestion a. Protein digestion begins in the duodenum – stomachb. Pancreatic enzymes are most important – gastricc. Pepsinogen I/II ???????? d. Is largely completed in the small intestine – yese. Commences upon the action of saliva – no pepsin in saliva

11.Regarding fat digestion a. Fat digestion begins in the duodenum – mouth – lingual lipaseb. Colipase is required for digestion – aids, not essentialc. Bile salts on their own are most important to emulsify fats – lecithin and bile salts

12.Regarding absorption, which is incorrect a. Glucose absorption is an example of secondary active transport b. Galactose is absorbed by the same mechanism as glucose c. Fructose is absorbed by facilitated diffusion d. Insulin regulates glucose absorption in the intestine

13.Which is true of faeces a. 50 ml is produced per day on average b. it is chiefly formed from protein breakdown products – waterc. solids form 75% of its composition – water is 75%d. the solid portion contains 30% bacteria – yese. the brown colour is due to melanin – bile

14.Which of the following is a nutritionally essential amino acid a. glycine b. histidine – this one is ‘semi-essential’c. tryptophan – apparently not, although others sources say it isd. tyrosine e. cysteine

15.With respect to absorption in the gut a. vitamins A, D and K are absorbed in the small intestine

16.With regards to cholesterol which of the following is FALSE a. it is present in animals b. plants contain cholesterol – FALSEc. it is essential to the structure of the cell membrane d. it is a precursor to bike acids

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17.Concerning pancreatic secretions a. the pancreas secretes gastrin – stomachb. pH is 6.0 – 8c. it contains anti-trypsin molecules – to keep enzymes inactive in pancreas. Activated by enterokinase in SId. it contains an enzyme converting polysaccharides to monosaccharides – poly to disaccharides

18.Gastric emptying a. takes 1-3 hours

19.The majority of water ingested or secreted in the bowel is usually absorbed in the a. stomach / duodenum b. jejenum – thisc. ileum d. ascending colon e. descending colon

20.Protein digestion a. commences upon activation of saliva b. is largely completed by the small intestine – yes

21.Where are the vitamins A, D, E and K absorbed a. stomach b. proximal small bowel – yesc. colon d. distal small bowel e. ileum

22.Where are Vits A,D,K absorbed a. stomach b. proximal small bowel c. terminal ileum d. duodenum e. ascending colon

23.Where is most fat absorbed

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GASTROINTESTINAL SYSTEM

1. The liver synthesizes all of the following except a. Albumin b. Fibrinogen c. Complement d. Gamma globulins – this

2. What causes increased gastric acid, mucosal proliferation a. GIP b. Gastrin – tis

3. Regarding pancreatic enzymes/juice all are correct, EXCEPT a. trypsin inhibits trypsinogen –thiis

b. is rich in bicarbonate c. has a PH of 8.0

4. Swallowing a. voluntary first, than reflex

5. Gastric emptying a. occurs in approximately 2 hours – this

b. depends on osmotic pressure in the duodenum c. depends on PH in the duodenum d. is slowed down with metaclopramide

6. Gall bladder functions; which is correct a. responds to CCK – this

b. secretes cholesterol c. secretes lecithin d. increases the pressure of the biliary system e. alkalinises bile acids

7. Regarding gastric emptying – ?all of them – osmotic pressure in duodenum is the key.a. occurs in 1-3 hours b. is not related to pH in the duodenum c. duodenal pressure is not important

8. The pH of pancreatic secretions is a. 5.0 b. 6.0 c. 7.0 d. 7.5 – this

e. 6.5

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9. What role does the autonomic nervous system have in the GIT a. permissive b. regulatory – this one

c. essential – no, can function without connections

10.Secretin causes a. increased gastric motility b. increased volume of secretions – this one

c. an enzyme rich secretion

11.Gastric emptying is a. not related to pH in duodenum b. duodenal pressure is not important c. normally takes 1-3 hours to empty – this (unless osmotic pressure is an option)

12.Which cells secrete intrinsic factor a. Chief cells b. G cells c. K cells d. S cells e. Parietal – thjis

13.Which cells secrete intrinsic factor a. G cells b. Chief cells c. Parietal cells – thuis

d. K cells e. S cells

14.109) With regard to the parasympathetic nerve supply of the gut it is a. essential b. non-essential c. modulatory – this

d. passive

15.Intrinsic factor a. is produced by the gastric parietel cells – yes

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BLOOD

1. 16 2,3 DPG levels are increased in a. stored blood – no decreasedb. chronic hypoxia – YES, also in anaemia and at high alititudec. decreased temperature – nod. hypocarbia – not a factore. acidosis – no - decreased

2. 29 2,3, DPG is decreased in all except. a. polycythemia b. testosterone – increased – must be this onec. acidosis – decreasedd. left shift of O2 dissociation curve – decerase in 2,3,DPG shifts curve to lefte. stored blood – decreased

3. With regards to lymph a. has no clotting factors b. its protein content is dependant on the area it is from c. is not dependant on the colloid pressure of the capillary

4. Regarding haemaglobin a. Fe3+ binds oxygen – no, Fe2+ binds oxygen – becoming oxygenated to Fe3+b. HbF has no beta chain – true – alpha and gamma sub-units insteadc. Globin is synthesised from porphyrin – no

5. What causes a reduction in Hb-O2 affinity a. acidosis – yes – allows o2 to be released…b. increased 2,3-DPG – yesc. increased temperature – yesd. growth hormone – yes, as increases 2,3 DPGe. all of the above – is the correct answer

6. Regarding the rhesus blood group system; which is correct a. 50% of people are Rh positive b. C, D and E are the most antigenic ?

7. Regarding Hb a. Fe3+ binds O2 – falseb. HbF has no beta chain – truec. Globin is synthesized from porphyrin – false

8. With regards to lymph a. has no clotting factors b. its protein content depends on the area it is from c. is not dependant on the colloid pressure of the capillary

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9. 2,3 DPG levels increase in all of the following circumstances except a. Chronic hypoxia – does increaseb. Androgens – does increasec. Natriuesis – this one

10.Regarding the resus antigen/system a. Rh+ve individuals have C, D, E antigens – could be c and e.

b. 50% caucasions are D +ve – 85%

c. Do not develop anti-D antibodies without exposure of D-ve individuals to D+ve red cells – this one

11.Regarding granulocytes a. All have cytoplasmic granules – yes.

b. Basophils are identical to mast cells c. Eosinophils phagocytose viruses d. Neutrophils have a half life of 4 days

12.Increased 2,3 DPG occurs with all the following EXCEPT a. chronic hypoxia b. acidosis – this one – 2,3 DPG decreased in acidosis – as red cell glycolysis inhibited by low pHc. androgens d. thyroid hormones e. none of the above

13.The major mechanism for transporting CO2 in the blood is a. carboamino groups – about 6%b. dissolved in blood by Henrys law – which states that at constant temp the amount of gas dissolved in a liquid is

proportional to the partial pressure of that gas in equilibrium with the liquidc. haemoglobin d. bicarbonate – nearly 80% is HCO3-e. none of the above

14.The haemoglobin dissociation curve moves up and to the left with a. increased H+ concentration – no, to the right with decreased pHb. hypothermia – yesc. increased 2,3 DPG – no, this decreases O2 binding affinityd. hypercarbia –which will decease pH – so shift curve to righte. all of the above

15.Which statement concerning iron is FALSE a. iron is absorbed in the duodenum b. it is the major component of myoglobin – this onec. excess can de associated with diabetes – in haemochromotosis

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16.Regarding iron a. it is absorbed in the duodenum – yes

b. 70 % is present in myoglobin – in Hb

c. a deficiency can cause diabetes – excess

d. the amount absorbed ranges between 10-20% – 3-6%

e. mobilferin binds less iron in iron deficiency

17.Haemoglobin a. the globin portion is a porphyrin – no, heme is made up of porphyrin and an atom of Fe2+b. the difference between haemoglobin and myoglobin is haeme – does have a sinlge heme groupc. foetal haemoglobin has no beta chains – true – alpha and gamma

18.Which of the following is the largest a. fibrinogen – 340,000 daltonsb. haemoglobin – 68,000 daltons al together, 17000 daltons per subunitc. albumin –67,000 daltonsd. gamma globulin – variable sizes…e. alpha 1 antitrypsin – 52,000 daltons

19.The liver synthesises all of the following EXCEPT a. albumin b. fibrinogen c. gamma globulins d. complement e. erythropoetin

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THE HEART

1. Regarding isovolumetric contraction phase of cardiac cycle – beginning of systole – mitral valve shut, before aortic valve opens.

a. Aortic valve is open – no – aortic valve opens at end of isovolumetric contractionb. Associated with decreasing intra-aortic pressure – (must be this one as others are wrong?)c. Mitral valve is open – no mitral valve must be closedd. Backflow in aorta – no this occurs at beginning of diastole

2. regarding ECG a. ST is refractory period – no. R-T contains absolute and relative refractory periodb. PR is atrial systole - yes

3. R wave on ECG a. Corresponds to Na influx yesb. Corresponds to Ca influx no, this is later and slowerc. Corresponds to Ca efflux no later and slower still

4. Fasting energy for the heart comes from a. gluconeogenesis b. amino acids c. glucose d. FFA – this onee. glycerol

5. In a healthy male who is running a. O2 extraction can increase 600% - no 1000%b. maximal heart rate depends on fitness – no depends on lots of things!c. maximal heart is independent of age – maximal HR decreases with aged. cardiac output can increase 1500% - no 700%e. systolic BP rises and diastolic BP falls or stays the same - yes

6. In A man with congestive heart failure, what is the most likely cause? a. increased rennin production – ???? (think that this is an effect of CCF, due to decreased renal perfusion)b. decreased blood pressure – no, hypertensionc. increased albumin – no, exacerbated by low albumind. increased atrial pressure - ???? (failure of ventricles, back pressure etc. Increased atrial pressure = high preload?)e. decreased angiotensin II`production – no this is a treatment of CCF

7. Regarding the cardiac action potential a. Unlike the nerve action potential there is no overshoot – no overshoot to about 20mVb. The plateau phase is based on K+ efflux – no due to Ca2+ influx (there is K+ efflux too)c. The plateau phase can be up to 100 x longer than depolarisation must be this one (1-2ms vs 100-200ms) d. The relative refractory period prevents tetanus – no this is the absolute refractory period

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8. Slowest conducting cardiac tissue is a. Purkinje System - fastestb. AV node – yes, slowest, along with SA nodec. Atrial Pathways – no moderate conductiond. Ventricular muscle – no moderate conductione. Bundle of His – no moderate conduction

9. Regarding autonomous innervation of the heart a. SA node and AV node are mainly supplied by sympathetic nervous system – no mostly parasympathetic toneb. Sympathetic stimulation maximally increases cardiac output by 30% – MAXIMAL increase must be 100% ++c. Parasympathetic stimulation can decrease cardiac output by up to 80% – has to be this one?

10.Regarding the blood supply of the heart a. the heart receives 15% of the CO at rest – 5% to heart, 15% brain, 15% skel mm, 30% liver, 24% kidneyb. left ventricular supply may be decreased by tachycardia – yes

11.A fit 20 yo male can increase SV during strenuous exercise; which is correct –NOTE: STROKE VOLUME, NOT COa. increase < 200% – this oneb. increase 300% c. increase 500% d. increase 400% e. increase 700%

12.Cardiac muscle; which is correct a. calcium release from sarcoplasmic reticulum initiates contraction – trueb. relative refractory period is longer than absolute refractory period – no, ARP much longerc. time of contraction is less than action potential – false, 1.5times longer than APd. it can display tetanus – cannot

13.A 42 yo male presents with chest pain. It is attributed to coronary vessel vasoconstriction. What is the most likely cause

a. alpha 1 adrenoreceptor agonist activity – must be this oneb. hypoxia

14.In a normal state, which is the heart’s principal energy source a. glucose – 60% fat, 35%carbo, 5%ketones / amino acids

15.In the fasting state, which of the following meets most of the hearts basic caloric requirements a. free fatty acids – more fat in starvation – 50% of which is FFA.

b. glucose c. lactate d. protein

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16.A fit 20 year old male undertaking strenuous exercise can a. increase SV <200% – this oneb. increase SV 300% c. increase SV 500% d. increase SV 400% e. increase SV 700%

17.If the autonomic supply is removed from the heart a. HR 150/min – rate would be 100/minb. HR 40/min – this is (probably) referring to ventricular ratec. Decreased contractility – probably this one

18.The cardiac output during exercise can increase by a. 200% b. 500% c. 700% – this oned. 300% e. 600%

19.During isovolumetric contraction a. mitral valve opens – closedb. decreased aortic pressure – yesc. may have reversed flow in the aorta – during isovolumetric relaxation

20.Cardiac output is changed accordingly in all of the following circumstances except a. Increased by up to 700% in exercise – it is b. Increased on eating – it is by 30%c. Decreased by sleep – no change, nor with temp change. Decreased on sitting / standing from lying

21.The slowest conducting type of cardiac tissue is a. Bundle of His b. Ventricular muscle c. Purkinje system – this is the fastestd. Atrial pathways e. AV node – this one

22.Work of the heart is best approximated by a. Heart rate x ejection fraction – something like SV x MAP

23.Regarding the blood supply of the heart a. The heart recieves 15% of CO at rest – 5%b. Left ventricular supply may be decreased by tachycardia – yes

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24.Regarding cardiac output in exercise a. It can increase 200% b. It can increase 500% c. It can increase 700% – yesd. It can increase 300% e. It can increase 400%

25.In exercise in a fit healthy young male a. Stroke volume increases less than 200%– yes b. Stroke volume increases more than 300% c. Stroke volume increases more than 400% d. Stroke volume increases more than 700%

26.Isovolumetric ventricular contraction a. Occurs directly post atrial systole – yes

27.Bradykinin – vasodilator, non-vascular smooth muscle constrictora. is named after it’s effect on the heart b. stimulates cutaneous smooth muscle constriction – if referring to vascular bed in skin, then no c. stimulates GI smooth muscle constriction – non-vascular smooth muscle contraction

28.Under basal conditions the percentage of the hearts caloric needs met by fat is a. 70% b. 60% – this onec. 50% d. 40% e. 30%

29.With respect to the cardiac cycle a. isovolumetric contraction phase immediately follows the phase of atrial systole – yes

30.Myocardial contractility is decreased by all of the following EXCEPT a. acidosis – trueb. barbiturates – true c. hypercarbia – trued. bradycardia – truee. glucagon – increases contractility

31.Cardiac output is decreased by a. sleep - no changeb. exercise - increased – up to 700%c. pregnancy in the first trimester - increasedd. sitting from a lying position – this onee. all of the above

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32.With regard to the cardiac cycle a. phase 1 represents atrial systole – yesb. the aortic valve opens at the beginning of phase 2– 2=isovolumetric contraction (AV shut) c. the T wave of the ECG occurs during phase 4 – phase 3d. the second heart sound is due to mitral valve closure – Aortic V closuree. the c wave is due to tricuspid valve opening – no, tricuspid valve bulging into atria on ventricular contraction

33.With regard to the 12 lead ECG a. lead 11 is at 90 degrees for vector analysis – about 60 degrees b. V2 is placed in the 3rd left interspace – 4thc. Septal Q waves are predictable in V2 – no q wave in V1 or V2d. +130 degrees is still a normal axis – -30 to +110e. the standard limb leads record the potential difference between 2 limbs –between 2 points? then yes

34.With regard to cardiac action potentials a. cholinergic stimulation increases the slope of the pre-potential – decreasesb. the resting membrane potential is increased by vagal stimulation – more negativec. phase 0 and phase1 are steepest in the AV node – least steep in AV and SA nodesd. the Twave is the surface ECG manifestation of phase 1 – no, phase 3e. the action potential in the AV node is largely due to calcium fluxes – yes

35.The most rapid conduction of electrical impulses occurs in the a. AV node – slowestb. Atrial pathways c. Bundle of His d. Purkinje system – this onee. Ventricular system

36.The R wave of the ECG is due to a. calcium influx b. chloride influx c. sodium influx – this oned. potassium efflux e. chloride efflux

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THE CIRCULATION 1. Proportion of cardiac output that goes to kidneys

a. 10% b. 15% c. 25% this one (28%liver, 15% brain, 10% skin, 15% skel mm, 5% heart. Est CO 4500ml/min)d. 35% e. 50%

2. Which organ receives the following blood flow a. Heart 250ml/min yesb. Liver 2000ml/min 1500ml/minc. Kidney -1260ml/mind. Skin -500ml/min

3. Regarding flow a. Proportionate to viscosity - inversely proportional b. Proportionate to length -inversely proportionalc. Proportionate to pressure difference at 2 ends of tube - yes d. Proportionate to mean pressure in tube - ??

4. If tube diameter is increased from 1 to 2 cm a. Flow is doubled - increased by factor of 16b. Flow is halved c. Resistance is doubled d. Resistance is increased 16x e. Resistance is decreased 16x - this one (resistance inv proportional to r to power of 4)

5. Resistance in a narrow tube is inversely proportional to a. average pressure in tube - why not this one?b. length of tube -proportionalc. viscosity - proportionald. pressure gradient - this one?

6. When blood goes to systemic capillaries a. there is a shift of ions from red cells to plasma -???b. Hematocrite is unchanged compared to arterial blood - hematocrite must rise due to loss of plasma volumec. PH increases - falls as venous blood has more CO2 than arterial blood – therefore more acidicd. cell size decreases - increases due to chloride shifte. Cl goes from red cells into interstitium -???

7. Regarding wall tension and dilation in vessels a. mean pressure increases as radius increases

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8. Flow through a narrow tube is proportional to a. viscosity b. length c. average pressure in the tube d. pressure gradient - this one

9. What is common to all capillary beds? a. all are patent b. are 10-20 mm in diameter c. have a continuous basement membrane - not if fenestratedd. have intracellular fenestrations - surely INTERcellular as opposed to INTRAcellular? But not all cap beds are

fenestrated

10.The part of the CVS with the largest total cross-sectional area is a. Arteries - 20cm3 in arteries, 4.5cm3 in aortab. The large veins - no only 40cm3, +18cm3 in vena cava.c. The capillaries - this – total cross sec area 4500cm3

11.Regarding capillaries a. Arterioles have a lower ratio of smooth muscle to diameter than large arteries - false - contain less elastic tissure,

but more smooth muscleb. Capillary flow is regulated by precapillary sphincters and metarterioles - truec. Have the largest cross-sectional area - trued. Contain 8% of the total blood volume - no 5%

12.Lymph a. Has an increased protein content compared with plasma - false, generally lower than plasmab. Has a differing protein in different areas - true, greatest in liver, smallest (0) in choroids plexus, ciliary bodyc. Fats cannot enter lymph - falsed. Has no lymphocytes - falsee. Contains no clotting factors - false.

13.EDRF a. shares a similar mechanism of action to GTN - yesb. activates adenyl cyclase - causes production of cGMP by guanyl cyclasec. is the common pathway in the action of adenosine and histamine – no, independent of NOd. antagonises the action of thromboxane - doesn’t work through same pathways but could be argued to oppose

action (vasoconstriction vs vasodilation)e. is synthesised by a magnesium dependent enzyme - nitric oxide synthase contains heme group, affected by

Ca2+ concentrations

14.All of the following explain venous blood flow EXCEPT a. oncotic pressure gradient - affects flow of fluid out of / into capillary bedsb. smooth muscle contraction - affects venous tonec. skeletal muscle contraction - pumps blood backd. the pumping of the heart - maintains blood pressuree. intrathoracic pressure variations - alters preload etc

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15.The ‘c’ wave of the jugular pulse is due to a. atrial systole - ‘a’ waveb. atrial contraction against a closed tricuspid valve in complete block - cannon wavec. the increase in intrathoraci pressure during expiration - changes height of JVP, not form of waved. transmitted pressure due to tricuspid bulging in isovolumetric contraction - yese. the rise in pressure before the tricuspid valve opens in diastole - ‘v’ wave

16.The poiseuille-Hagen formula tells us that a. longer tubes can sustain higher flow rates - no, inversely proportionalb. flow is directly proportional to resistance - no, inversely proportionalc. flow will be doubled by a 20 % increase in vessel diameter - yesd. turbulent flow is predicted in high velocity vessels - Reynolds numbere. why the venous capacitance is important in cardiac output - ?Starling force?

17.The greatest percentage of the circulating volume is contained within a. capillaries - greatest surface area but only 5% volumeb. large arteries - 8%c. pulmonary circulation - 18%d. the heart - 12%e. venules and veins – yes 54%

18.Which of the following organs receive the largest amount of the bloods circulation per kg of tissue a. heart 84b. kidney 420ml/100g/minc. brain 54d. liver 58e. adrenal ? – proportion of renal artery flow

19.All capillaries have a. a diameter of 10-20 mm - 5-10micrometresb. a basement membrane - true

20.Regarding Poiselle-Hagen flow in vessels , the flow in a vessal is proportional to a. pressure difference between the two ends -yesb. radius -to power of 4c. viscosity - inversely proportional

21.With respect to isovolumetric contraction of the ventricle it is associated with a. decreasing aortic pressure -?this oneb. aortic back flow - occurs when aortic valve closes after systolec. open mitral and tricuspid valves - closedd. open aortic and pulmonary valves - valve opens at end of isovolumetric contractione. none of the above - ?this one

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22.The part of the cardiovascular system with the largest cross sectional surface area is a. arteries b. capillaries -yesc. large veins d. aorta e. vena cava

23.The systemic circulation peripherally has a. decreased red cell size - increased due to chloride shift, and co2 Hb – more water in cell.b. decreased pH - this onec. increased chloride - decreased in plasma – as has shifted into RBCsd. decreased HCO3- - increased in plasma – in exchange for Cl in RBCs

24.How can the pressure be reduced in the femoral vein a. skeletal muscle pump action b. increased cardiac output - this onec. decreased cardiac output

25.What percentage of the blood is contained within the venous system a. 40 b. 50 - 54%c. 65 d. 70 e. 30

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RESPIRATORY PHYSIOLOGY 1. Asccending to altitude

a. Partial pressure nitrogen decreases – must dob. Decreasing CO2 and decreased pH inhibit respiration – no, respiratory alkalosis decreases response to hypoxia

2. Regarding volumes of lungs (?in upright)a. Ventilation greatest in middle zone – ventilation and perfusion greatest at the basesb. Perfusion greatest at the base –yesc. VQ directly proportional to gas exchange – ??d. VQ inversely proportional to gas exchange –??

3. Causes of pulmonary vasoconstriction a. Altitude – hypoxia causes vasoconstrictionb. Exercise – little or no effect, possibly vasodilation

4. Regarding ventilation a. Anatomical deadspace is 1ml/kg – no approx 1ml/lb not kgb. Lung units with high VQ have decreased alveolar minute ventilation – yes, apex has highest V/Q in normal lung,

but lowest of both ventilation and prefusionc. Increased RR decreases anatomical dead space –???not sure, but possibly increases if breathing shallower?

5. Regarding ventilation a. At the end of inspiration chest wall recoils and pulls lungs back to original position – ??lung recoil pulls chest wall

back?

6. Airway resistance a. is independent on lung volumes –??? Think sob. is equal in inspiration and expiration – no, varies with airway radius – greater during inspirationc. decreases while breathing through the nose – no increasesd. decreases with forced expiration – no increases as forced expiration collapses airways

7. Compliance a. is different in inspiration compared with expiration – yes, slightly greater with expirationb. independent of lung volume – no, depends on lung volumec. decreased with age –???d. decreased with emphysema – no, increased with emphysema, decreased with fibrosis

8. Regarding the Respiratory Quotient (RQ) – amount of 02 used to produce each CO2 molecule in the tissuea. RQ brain = 0.95 – 0.97-0.99b. RQ fat = 0.95 – about 0.7 (lots of O2 needed to produce each CO2)c. RQ Carbohydrates= 0.95 – 1 (less O2 needed to produce CO2 as carbohydrate contains oxygen)d. RQ brain > 0.95 – yese. RQ brain < 0.95 – no

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9. What is de oxygen pressure in the bronchioli at an altitude where barometric pressure is 500 mm Hg, breathing 30% O2 – 0.3 x (500 – 47) - 40/0.8 = 86mmHg

a. 60 mm Hg b. 70 mm Hg c. 80 mm Hg d. 90 mm Hg – this is closeste. 100 mm Hg

10.If compliance of the lung is 30 mL/cm H20 and the average tidal volume is 600 mL, the pressure change per breath is: – compliance = change in volume / unit change in pressure. Pressure change = change volume / compliance? = 20cmH2O

a. 0.2 cm H20 b. 0.5 cm H20 c. 2 cm H20 d. 18 cm H20 e. 20 cm H20 – this one.

11.What causes a decrease in airway resistance (similar question ?) a. breathing through nose – no – will increase airway resistance – high volume at nose, small diameterb. small lung volume – c. exhale forcefully – increases – as collapsing airways

12.Which of the following decreases pulmonary vascular resistance a. altitude – causes vasoconstriction (relative hypoxia). Little or no vasodilation with exercise.

13.What effects will be noticed after 10 minutes of hypoxia (pO2 50 mm Hg) - need to read West.a. decreased pH – no, respiratory alkalosisb. increased pCO2 – decreased pCO2 as hyperventilating

NB: no option available on changes in O2 saturation

14.In walking down the street, what causes an increased respiratory rate a. decreased PO2 b. increased PCO2 c. decreased pH d. none of the above – Po2, PCO2 and pH remain constant during moderate exercise.

15.What causes a decrease in airway resistance a. breathe through nose – nob. small lung volume c. exhale forcefully – no

16.Given that the intrathoracic pressure changes from –5cmH2O to –10 with inspiration and a TV of 500 mls, what is the compliance of the lung?

a. .01 b. .1 – 0.5litres / 5cmH2O = 0.1l/cmH2O L/cmH2O or mL/cmH2O?c. 1.0 d. 10 e. 100

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17.Compliance is a. Dependant on lung volume – yes,

18.Surfactant a. Increases compliance – trueb. Is produced by type 1 pneumocytes – no, type 2.c. Is absorbed by type 2 pneumocytes – true.

19.Residual volume in a 70kg man most closely approximates a. 1.0 litre – 1.2 litres in menb. 2.0 litre c. 3.0 litre – d. 4.0 litre e. 5.0 litre

20.Permanent high altitude is associated with all of the following EXCEPT a. increased arterial blood HCO3- b. increased arterial blood 2,3 DPG – yesc. increased pulmonary artery pressure – yesd. increased alveolar ventilation – no – after 4 days, ventilation returns to normale. could have a normal PaCO2 – true

21.With regard to the distribution of pulmonary blood flow a. typically there is a zone at the apex which is not perfused – not typicallyb. the mean pulmonary arterial pressure is 8 mmHg – about 15mmHgc. hypoxia leads to pulmonary dilation – vasoconstrictiond. the net balance of the Starling forces keep the alveoli dry – ??e. in some areas flow is determined by the arterial/alveolar pressure difference – yes – waterfall effect

22.With regard to pulmonary gas exchange a. transfer of nitrous oxide is perfusion limited – yesb. diffusion is inversely proportional to the partial pressure gradient – surely proportional??c. the diffusion rate for CO2 is double that of O2 – 20 times d. at altitude the profound systemic hypoxemia favours oxygen diffusion –deoxyhemogobin has lower affinity for O2

than oxyhemoglobin, but does this answer the question???e. transfer of O2 is diffusion limited – no perfusion limited – reaches equilibrium in 0.3secs

23.Which of the following is associated with the least increase in airway pressure –????a. forced expiration b. nasal breathing c. very low lung volumes

24.Surfactant a. increases compliance – true, by decreasing alveolar surface tension, also prevents pulmonary oedema, b. is produced by type 1 pneumocytes – no, type 2

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25.A permanent inhabitant at 4,500 feet a. has a high alveolar PO2 – b. has a decreased 2,3, DPG – no, will be increasedc. is highly sensitised to the effects of hypoxia d. shows increased ventilation – no, normal after 4-5dayse. may have a normal HCO3-

26.What is the PO2 of alveolar air with a CO2 of 64 and a respiratory quotient of 0.8 – pAO2 = piO2 – (pACO2 / R) + 2- 0.21 x 713 – (64/0.8) + 2 = 72 (not sure we did a +2???)

a. 35 b. 52 c. 69 – this oned. 72 e. 80

27.What is the compliance of a lung if a balloon is blown up with 500ml of air with a pressure change from –5 to –10 a. 0.1 – change in volume / change in pressureb. 1 c. 10 d. 100 – depending on units usede. 200

28.When walking at a steady pace the increase in respiratory rate is due to a. decreased PO2 b. increased CO2 c. increased pH d. increased pH CSF e. none of the above – psychological stimuli

29.Which of the following are a cause of increased pulmonary vascular resistance a. altitude – yes, hypoxia vasoconstrictionb. forced expiration – airway resistance

30.What is the maximal volume left in the lung after maximal forced expiration a. 0.5 b. 1.0 – this one = residual volumec. 2.0 d. 3.0 e. 3.5

31.Compliance is a. dependent on lung volume – apparently

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32.Pulmonary vascular resistance a. increases as venous pressure rises b. is increased at both low and high lung volumes – truec. is decreased by histamine – trued. increases with recruitment – decreases with recruitment – same amount of blood flows through more vesselse. is increased by muscular pulmonary arterioles which regulate flow to various regions of the lungs

33.Compliance of the lung is reduced by all the following EXCEPT a. fibrosis b. consolidation c. emphysema – this one – increases complianced. alveolar oedema e. high expanding pressures

34.In control of ventilation the medullary chemoreceptors respond to decreased a. O2 tension b. CO2 tension c. H+ concentration – this one – CO2 crosses BBB and hydrates to H2CO3 etcd. H+ conc and CO2 tension e. H+conc, CO2 tension and PO2

35.Laplaces law a. explains the observed elastic recoil of the chest b. explains the tendency of small alveoli to collapse – this onec. determines the change in volume per unit change in pressure – compliance d. tells us the pressure is inversely proportional to tension – P = T / Re. all of the above

36.The Haldane effect refers to a. the shape of the CO2 dissociation curve b. the carriage of O2 according to Henrys law c. the chloride shift that maintains electrical neutrality – chloride shiftd. the dissociation constant for the bicarbonate buffer system e. the increased capacity for deoxygenated blood to carry CO2 – this one

37.The anatomic dead space a. varies with minute ventilation b. is typically 150 mls – this onec. will increase in COPD d. is alveolar minus the physiological dead space e. all of the above

38.Regarding the diffusing capacity of the lung a. O2 passage is diffusion limited – perfusion limitedb. Diffusion is directly proportionate to the surface area of the alveolocapillary membrane and inversely proportionate

to thickness – true

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RENAL SYSTEM 1. Regarding the bladder

a. There is a relatively constant wall tension as volume increases – no, constant pressure. Tension increases as radius increases

b. There is an increasing pressure if volume increases – no, see abovec. Sympathetic nerves initiate micturiction – sympathetic nerves play no part in micturitiond. Urge to void occurs at 150 mls – true, fullness at 400mls

2. Regarding renal H+ handling –????a. Increased H+ ingestion causes increased H+ secretion b. Increased H+ ingestion causes decreased HCO3 secretion c. ECF K is inversely proportionate to ECF H+

3. Regarding permeability and transport in the nephron a. Thin ascending loop of Henle is permeable for water – descending permeableb. Thin ascnding loop of Henle has largest permeability for NaCl – yepc. Thin descending loop of Henle is impermeable to water – permeabled. Collecting tubule only minimally permeable for water – depends upon ADH action

4. In the kidney, Na is mostly reabsorbed with a. HCO3 b. glucose c. Cl – this one – in Na- 2Cl-K cotransporter in ascending LoHd. Ca e. K

5. Regarding the bladder a. the urge to void occurs at 50 mL – 150ml, not 50mlb. there is a relatively constant pressure as volume increases – yes (P=2T/r)c. sympathetic nerves to the bladder initiate micturition – no

6. Composition of normal urine; which is correct a. no protein – trace amounts surely, but probably this oneb. constant SG of 1.010 – not constantc. pH is acidic – close to neutrald. urine output typically 500 mL/day– normally 1-2L/day

7. Regarding the renal handling of H+/ K+ a. H+/K+ are inversely proportional

8. With regard to renal handling of K+ a. It is reabsorbed proximally and secreted into the distal tubule – this oneb. It is absorbed and secreted proximally

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9. With regard to the kidney a. Has optimum autoregulation over a range of 60 - 100 mmHg – no 90-220mmHgb. Medullary blood flow is greater than cortical blood flow – no, cortical higher than medullary (5ml/g/min vs 2.5max)c. Prostaglandins decrease medullary blood flow –??d. Prostaglandins increase cortical blood flow –??

10.Regarding the bladder a. The urge to void occurs at 50mls – 150mlb. There is a relatively constant pressure as volume increases – yesc. Sympathetic nerves to the bladder initiate micturition –no

11.The filtration fraction of the kidney is – GFR/RPF. GFR remains constant even if RPF changes (eg with change in systemic BP)

a. 0.1 b. 0.2 –this onec. 0.3 d. 0.4 e. 0.5

12.In the kidney, Na+ is mostly reabsorbed with: a. HCO3 b. Glucose c. K+ d. CA++ e. Cl – this one possibly

13.Within the bladder a. the first urge to void is at 400 mls – no, 400ml is fullness.b. intravesical pressures can remain constant over a range of volumes – truec. voiding reflex is dependent on sympathetic control – independentd. parasympathetic reflex controls external urethral sphincter – somatic nerves, via pudendal

14.The hypothalamus is essential for a. renal function – makes ADH

15.With a fall in systemic blood pressure a. GFR falls more than renal plasma flow – no, other way roundb. There is efferent arteriolar constriction – this one, due to angiotensin IIc. The filtration fraction falls – no, rises (GFR/RPF)d. There is no efferent arteriolar constriction – no, there ise. GFR does not change – can do

16.What is the filtration fraction of the kidney ( GFR/RBF ) a. 0.1 b. 0.2 – yupc. 0.3 d. 0.4 e. 0.5

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17.The osmolarity of the pyramidal papilla is –???a. 400 b. 800 c. 1200 d. 1600 e. 2000

18.What is the major stimulus for the secretion of ADH a. hyperosmolarity – yes.

19.Hypokalemic metabolic alkalosis is associated with a. carbonic anhydrase inhibition – hyperchloraemic acidosisb. diuretic use – loop diureticsc. chronic diarrohea – no change in pH

20.Which of the following would be best used for measuring GFR a. radiolabelled albumin b. inulin – thisc. deuterium oxide d. tritium oxide e. mannitol

21.Given the following values calculate the GFR: Plasma PAH 90: Urine PAH 0.3: Plasma inulin 35: urine inulin 0.25: Urine flow 1 ml/min: Hct 40% – ?figures and answers wrong? GFR= ([inulin]u x urine flow) / [inulin]p

a. 120 b. 150 c. 180 d. 240 e. 400

22.Where in the renal tubules does the intratubular and interstitial osmolality hold the same values a. thick ascending loop of Henle b. thin descending loop of Henle – this onec. distal convoluted tubule d. collecting duct e. none of the above

23.With respect to the GFR a. it can be equated to creatinine clearance – more or less

24.With respect to the renal handling of potassium a. potassium is reabsorbed actively in the proximal tubule – apparently so

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25.In the kidneys sodium is mostly reabsorbed with a. chloride – yes. Na-2Cl-K cotransporterb. bicarbonate c. glucose – less so by secondary active transportd. potassium e. calcium

26.The absorption of sodium in the proximal tubule a. reabsorbs 80% of the filtered sodium – 60%b. causes increasing hypertonicity – false, because water freely moves by osmosis as Na is pumped outc. is powered by Na+/H+ ATPase – Na/K ATPase in basolateral membrane. Na/H exchange in luminal membraned. shares a common carrier with glucose – true, secondary transport SGLT2e. all of the above – no

27.With regard to osmotic diuresis a. urine flows are much less than in a water diuresis – much higherb. vasopressin secretion is almost zero – false, maximalc. the concentration of the urine is less than plasma – no, always higher, but approaches that of plasma in osmotic

diuresisd. increased urine flow is due to decreased water reabsorption in the proximal tubule and loop of Henle – true e. osmotic diuresis can only be produced by sugars such as mannitol – BS

28.Renal acid secretion is affected by all the following EXCEPT a. PaCO2 – is – affects HCO3

- levelsb. K+ concentration – is – H-K ATPasec. Carbonic anhydrase – isd. Aldosterone – is, affects [Na], therefore exchange ratee. Calcium – this one

29.Glucose reabsorption in the kidney is a. a passive process – assoc with Na transportb. closely associated with potassium – falsec. the same in all nephrons – no – hence splayd. occurs predominantly in the distal tubule – no, proximal tubulee. resembles glucose reabsorption in the intestine – yes

30.Which of the following is the most permeable to water a. thin ascending loop of Henle – low permeabilityb. distal convoluted tubule – low permeabilityc. thin descending loop of Henle – this oned. cortical portion of collecting tubule – permeablee. thick ascending limb of the loop of Henle – low permeability

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31.With regard to urea –???a. it moves actively out of the proximal tubule – falseb. it plays no part in the establishment of an osmotic gradient in the medullary pyramids – falsec. all of the tubular epithelium is impermeable to urea except the inner medullary portion of the collecting duct – not

according to Wikipedia – also moves from interstitium -> lumen in ascending limb of LoHd. a high protein diet reduces the ability of the kidney to concentrate urine – increases abilitye. vasopressin has no effect on the movement of urea across tubular epithelium – false according to Wikipedia

32.Where in the kidney is the tubular fluid isotonic with the renal interstitium a. PCT b. DCT c. Proximal LH – descending LoHd. Distal LH

33.What is the osmolality of the interstitium at the tip of the papilla a. 200 b. 800 c. 1200 – probably this oned. 2000

34.What is the osmolality of the interstitium at the tip of the renal papilla a. 200 b. 800 c. 1200 –this one?d. 2000 e. 3000

35.In the kidney, Na is mostly reabsorbed with a. HCO3 b. Glucose c. K+ d. Ca2+ e. Cl- – this one

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ACID-BASE BALANCE 1. Regarding blood buffers. What is HCO3:H2CO3 ratio at PH 7.4? (table 39.5)

a. 10 -pH 7.1b. 16 -pH 7.3c. 1 d. 20 - this onee. 0.9 - pH 6.0

2. Regarding the anion gap a. Difference between cations including Na and anions including Cl- and HCO3 - not including – that it isb. Increased in hypochloremic acidosis secondary to NH4 ingestion - ????c. Decreased with decreased Mg/Ca - no, increased with decreased Ca/Mgd. Decreased when albumin is increased - decreased with decreased albumine. It consists mostly of HPO4, SO4 and organic acids - ??

3. Which H+ concentrations are compatible with life (Table 39.1 Ganong) - 0.00004 maybe? (range 0.00002 – 0.0001)a. 0.0004 meq b. 0.0004 meq c. meq d. 0.0002 meq e. 0.0008 meq

4. Which agent is most likely to produce the following blood gas result: pH 7.51, HCO3 50, pCO2 45 a. diuretic - lose Na and Cl-. Retain bicarbonate, volume deplete therefore relative [HCO3] increases therefore pH

rises.b. chronic diarrhoea - bicarbonate loss in stool, metabolic acidosis, low bicarbc. carbonic anhydrase inhibitor - causes Na, Cl, HCO3 loss in urine. acidosis

5. Regarding the anion gap a. it is the difference between cations not including Na and K and anions not including HCO3 -nob. it consists mainly of HPO4, SO4 and organic acids -?? Mainly of albumin acc. To Kumar and Clarkec. it is increased in hyperchloraemic acidosis due to ingestion of NH4Cl - normal anion gapd. it is decreased when albumin is increased - decreased with decreasee. it is decreased when Ca/Mg are decreased - increased

6. In respiratory acidosis, what would be the first metabolic compensatory response a. bicarbonate retention / elevation

7. Which substance does not represent an acid load to the body a. Fruit - gives alkalib. DKA c. CRF d. Ingestion of acid salts

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8. All of the following represent an acid load to the body EXCEPT a. DKA b. CRF c. Fruit - this d. Ingestion of acid salts

9. Which agent is most likely to produce the following blood gas result : pH 7.51 HCO3 50 PCO2 45 a. diuretic - this oneb. chronic diarrhoea c. carbonic anhydrase inhibitor

10.Hypokalaemic metabolic acidosis may be associated with a. Carbonic anhydrase inhibitors - no loss of K+b. Diuretic use - alkalosisc. Chronic diarrhoea - bicarb and K+ loss

11.The ratio of HCO3- ions to carbonic acid at pH 7.1 is a. 1 - pH 6.0b. 10 - this onec. 0.1 - acidic ++++

12.Regarding the anion gap a. It is the difference between cations including sodium and anions including Cl and HCO3 b. It is increased in hyperchloraemic acidosis secondary to ingestion of NH4Cl c. It is decreased when Ca/Mg decreased d. It consists mostly of HPO4 2- ,SO4 2- and organic acids e. It is decreased when albumin is increased

13.In a patient with a plasma pH of 7.1 the HCO3-/H2CO3 ratio is a. 20 - pH 7.4b. 10 - thisc. 1 - pH 6.0d. 0.1 e. 0.2

14.Which of the following best describes the changes found in uncompensated respiratory alkalosis a. decreased pH, HCO3- and PaCO2 b. increased pH and lowHCO3- and PaCO2 - this one. Normal HCO3 surely if uncompensatedc. decreased pH and HCO3- and normal PaCO2 d. increased pH low HCO3- and normal PaCO2 e. decreased pH increased HCO3- and normal PaCO2

15.In chronic acidosis the major adaptive buffering system in the urine is a. carbamino compounds - red cells onlyb. bicarbonate - ??c. ammonium - ??d. histidine residues - haemoglobine. phosphate - ??

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16.The following blood gases represent pH 7.32, pCO2 31mmHg and HCO3-20mmol/L a. primary metabolic acidosis - yes, but e more correctb. primary respiratory alkalosis - would expect high pHc. a picture consistent with diuretic abuse - water lost, bicarb retained, therefore HCO3 would be highd. mixed respiratory acidosis, metabolic acidosis - resp acidosis = high CO2e. partly compensated metabolic acidosis - compensated by low CO2, bicarb not yet caught up

17.The following gases are associated with PCO2 45 pH 7.57 HCO3- 30 a. acetazolamide treatment - causes NA, Cl, HCO3 loss in urine, therefore acidosisb. diuretic use c. diarrhoea - acidosis due to loss of bicarbonate

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