a) 2ml/min
b) 10ml/min
c) 20ml/min
d) 200ml/min
e) clearance cannot be determined from the information given
a) the loops of Henle act as counter current exchanges
b) solutes diffuse out of vessels conducting blood towards the cortex
c) water diffuses out of ascending vessels
d) water diffuses into the collecting ducts
e) counter current exchange is passive and can operate even if counter current
multiplication ceases
a) the GFR increases when flow through the distal tubule increases
b) the macula densa on the afferent arteriole is the sensor
c) the afferent arteriole is constricted by thromboxane A2
d) it is designed to maintain Na+
reabsorption
e) it does not operate in individual nephrons
a) greater constriction of efferent than afferent arterioles
b) greater constriction of afferent than efferent arterioles
c) constriction of afferent arterioles only
d) constriction of efferent arterioles only
e) has no effect on arteriolar constriction
a) total cross-sectional area of capillaries is 1000 times that of the aorta
b) the recoil effect producing continuous forward flow in the arterial system is
called the Poisevill-Hagen effect
c) 20% of the circulating blood is in the capillaries
d) average central venous pressure is 10.6mmHg
e) venicular dilation is a cause of oedema
a) NH4
+
is formed by reductive deamination of amino acids
b) most of the body’s urea is formed in the kidney
c) phosphorylcreatine is formed in the liver
d) creatinuria occurs normally in children
e) purines and pyrimidines are mainly sourced from dietary intake
a) 25-hydroxycholecalciferol is converted to 1,25-dihydroxycholecalciferol in
the distal convoluted tubule of the kidney
b) 1,25-dihydroxycholecalciferol receptors can be found in skin
c) when calcium levels are high, 24,25-dihydroxycholecalciferol levels are
also high
d) transport in plasma is by binding to haemoglobin
e) formation of 25-hydroxycholecalciferol is tightly regulated
a) absorbs most of the filtered sodium ions in the presence of aldosterone
b) absorbs glucose in the normal state
c) absorbs most of the filtered water in the presence of ADH
d) secretes hydrogen via secondary active transport
e) is almost entirely impermeable to urea
a) minimally filters protein, so plasma protein concentration is not altered
b) are supplied by an extensive anastomotic arterial network
c) lie distal to the juxtaglomerular apparatus
d) each receive approximately 20-25% of resting cardiac output
e) do not filter appreciable albumin since membrane pores are too small
a) develop tetany only at very high stimulation frequencies
b) develop less tension when stretched due to decreased actin-myosin
overlap
c) can derive only 5% of basal caloric requirement from fat
d) have a T-system located at the A-I junctions
e) remain absolutely refractory until the membrane potential repolarises to –
50mV
f) may contain a human ether-a-go-go gene which is associated with
uncontrollable Irish dancing when subjected to ether
