Physiology 2

     

 

11. The following cause a decrease in the arterial partial pressure of oxygen:

a) anaemia

b) carbon monoxide

c) hyperventilation

d) a rise in physiological dead-space

e) old age

 

a) total body vitamin C

b) HCl in the stomach

c) an intact colonic mucosa

d) total body iron

e) erythropoietin levels in the blood

 

13. If a normal person hyperventilates for 2 hours to an arterial PCO2 of 4 kPa: 

a) the cerebral blood flow decreases

b) the standard bicarbonate decreases

c) the Hb-oxygen dissociation curve shifts to the left

d) the ionised calcium concentration decreases

e) the plasma bicarbonate increases

 

a) excessive insulin secretion

b) alpha-adrenergic stimulation

c) beta-adrenergic stimulation

d) glucagon secretion

e) hypothermia

 

a) is important in prostaglandin synthesis

b) increases in the faeces with a decrease in bile secretion

c) is absorbed via the intestinal lymphatics

d) is mainly in the form of triglycerides

e) can be used as a source of ATP production

 

ANSWERS 11.FFFFT 12.FTFTF 13.TFTTF 14.TFTFF 15.TTTTT

 

a) 3% carboxyhaemoglobin

b) 5% methaemoglobin

c) 70% oxyhaemoglobin

d) 2% free haemoglobin

e) 2% fetal haemoglobin

 

17. In normal human lungs:

a) a low PO2 produces pulmonary vasodilatation

b) beta-2 agonists cause bronchoconstriction

c) pulmonary vascular resistance is increased by serotonin

d) pulmonary vascular resistance is decreased by histamine

e) pulmonary vascular resistance is decreased by noradrenaline

 

a) a decrease in urine volume

b) a decrease in the urinary excretion of sodium

c) a decrease in plasma cortisol level

d) an increase in the urinary excretion of nitrogen

e) an increase in the urinary excretion of potassium

 

a) bradykinin

b) adrenaline

c) calcium

d) vasopressin

c) histamine

 

a) a decreased haematocrit

b) a decreased total blood volume

c) a decreased serum sodium concentration

d) an abnormal glucose tolerance test

e) a reduced metabolic rate

 

ANSWERS 16.TFTFF 17.FFTFF 18.TTFTT 19.TFFFT 20.FTFTF

 

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a) receives most of its oxygen supply from the portal vein

b) has its highest oxygen tension at the centre of a lobule

c) produces heparin

d) has a normal portal venous pressure of greater than 20 mmHg

e) receives approximately 25% of the cardiac output

 

a) increases with noradrenaline

b) receives 50% of the cardiac output at rest

c) may cease during isometric contraction

d) increases with rhythmic contraction

e) increases with adrenaline

 

a) respiratory heat loss is insignificant under normal conditions

b) brown fat is an important source of heat production in neonates

c) shivering is due to impulses conducted via autonomic efferents

d) peripheral vasoconstriction increases heat production

e) sweating is mediated by sympathetic cholinergic neurones

 

4. Adrenaline:

a) is synthesized by demethylation of noradrenaline

b) increases coronary blood flow

c) increases free fatty acids in the blood

d) mobilizes glycogen stores from the liver

e) is metabolized in the plasma by monoamine oxidase

 

5. Glucagon:

a) is a positive inotrope

b) is produced by the beta cells of the pancreas

c) stimulates production of free fatty acids in the blood

d) release is increased in starvation

e) stimulates glycogen synthesis

 

ANSWERS 1.TFTFT 2.FFTTT 3.TTFFT (fundamentals of anaesthesia, 2nd edition page 446) 4.FTTTF 5.TFTTF

 

a) is a mucopolypeptide

b) causes a decrease in surface tension

c) results in the same surface tension for different sized alveoli

d) causes an increase in compliance

e) production is reduced after a prolonged reduction in pulmonary blood flow

 

a) produces a lengthening of the P-R interval

b) produces a lengthening of the R-R interval

c) is maximal with breath holding

d) is more marked during exercise

e) is more marked in 70 year olds than in 20 year olds

 

8. A pressure-volume curve can be used for measuring:

a) the work of breathing

b) functional residual capacity

c) anatomical dead space

d) compliance

e) respiratory quotient

 

a) as long as the entire action potential

b) the period when no further action potential can be stimulated

c) twice the length of the S-T interval

d) as long as the mechanical contraction

e) shorter for pacemaker tissue than for normal cardiac muscle

 

a) the glomerular filtration rate is approximately 125 ml/min

b) the 24 hour urine creatinine content is approximately 800 mg

c) urine specific gravity is always less than 1000

d) renal blood flow is approximately 20% of cardiac output

e) over 50% of water reabsorption from the glomerular filtrate occurs in the collecting ducts

 

ANSWERS 6.FTFTT 7.FTFFF 8.TFFTF 9.FTFFT 10.TFFTF