Renal, Resp, GI Tract, Nucleic Acids, Genetics Qs 2017

Question 1

Which one of the following factor(s) tend(s) to INCREASE the glomerular filtration rate (GFR):
Part1: decreased albumin concentration in plasma
Part2: vasodilation of the afferent (pre-glomerular) arteriole
Part3: vasoconstriction of the efferent (post-glomerular) arteriole
Part4: Options one and three are correct
Part5: all are correct

Answer 1

Part5: all are correct

Question 2

Which one of the following best describes the function of the countercurrent multiplier in the
nephron?.
Part1: change the blood levels of K+ ions
Part2: conserve K+ ions
Part3: decrease the concentration of NaCl
Part4: decrease the concentration of glucose
Part5: increase the concentration of NaCl

Answer 2

Part5: increase the concentration of NaCl

Question 3

During exercise which one of the following will occur?
Part1: Parasympathetic stimulation constricts afferent arterioles and reduces renal blood flow (RBF) and
glomerular filtration rate (GFR)
Part2: Parasympathetic stimulation relaxes afferent arterioles and increases RBF and GFR
Part3: Sympathetic stimulation constricts afferent arterioles and reduces RBF and GFR
Part4: Sympathetic stimulation constricts afferent arterioles and increases RBF and GFR
Part5: Sympathetic stimulation relaxes afferent arterioles and increases RBF and GFR

Answer 3

Part3: Sympathetic stimulation constricts afferent arterioles and reduces RBF and GFR

Question 4

The major humoral regulator of plasma sodium concentration is which one of the following?
Part1: ADH
Part2: Aldosterone
Part3: Angiotensin II
Part4: ANP
Part5: Renin

Answer 4

Part5: Renin

Question 5

A major stimulus for the release of antidiuretic hormone is which one of the following?
Part1: Increased Extracellular fluid (ECF) water concentration
Part2: Increased potassium levels in the Intracellular fluid (ICF)
Part3: Inhibition of osmoreceptors
Part4: Reduced blood volume
Part5: Stimulation of baroreceptors

Answer 5

Part4: Reduced blood volume

Question 6

Loop diuretics such as Furosemide function by which one of the following mechanisms?
Part1: Block Na+-K+-Cl- co-transporter
Part2: Block Na+ and K+ co-transporter and stimulate Cl- transportor
Part3: Decrease production of aldosterone
Part4: Increase production of aldosterone
Part5: Stimulate Na+ and K+ co-transporter and block Cl- transportor

Answer 6

Part1: Block Na+-K+-Cl- co-transporter

Question 7

In a healthy adult with a total lung volume of 6L, the amount of air present in the lungs at the
end of normal expiration is about:
Part1: 500 mL
Part2: 1000 mL
Part3: 1250 mL
Part4: 2500 mL
Part5: 5000 mL

Answer 7

Part4: 2500 mL

Question 8

In which pathologic condition is lung compliance increased?
Part1: Lung emphysema
Part2: Lung fibrosis
Part3: Respiratory distress syndrome
Part4: Restrictive disease
Part5: In both Option two and three

Answer 8

Part1: Lung emphysema

Question 9

Which one of the following will cause the oxygen-haemoglobin dissociation curve to shift to the
right?
Part1: CO
Part2: Decrease in tissue 2,3 DPG concentration
Part3: Decreased temperature
Part4: Increased CO2 concentration
Part5: Increased pH

Answer 9

Part4: Increased CO2 concentration

Question 10

The Bohr effect is explained by which one of the following?
Part1: diffusion of oxygen occurs slowly over long distances
Part2: greater pO2 outside the lungs than inside
Part3: haemoglobin binds carbon monoxide more readily than oxygen
Part4: haemoglobin unloads oxygen when it encounters low pH
Part5: oxygen is present in the atmosphere in relatively low concentrations

Answer 10

Part4: haemoglobin unloads oxygen when it encounters low pH

Question 11

Which one of the following agonists would be used for asthma patients?
Part1: a1-agonist
Part2: a2-agonist
Part3: b1-agonist
Part4: b2-agonist
Part5: b3-agonist

Answer 11

Part4: b2-agonist

Question 12

Which one of the following best describes the consequences of a right to left shunt in the lung?
Part1: pO2 will decrease, pCO2 will increase, detected by chemoreceptors will stimulate ventilation
Part2: pO2 will decrease, pCO2 will not change, not detected by chemoreceptors and no change in
ventilation
Part3: pO2 will increase, pCO2 will decrease, detected by chemoreceptors will reduce ventilation
Part4: pO2 will not change, pCO2 will increase, detected by chemoreceptors will stimulate ventilation
Part5: pO2 will increase, pCO2 will not change, detected by chemoreceptors will reduce ventilation

Answer 12

Part1: pO2 will decrease, pCO2 will increase, detected by chemoreceptors will stimulate ventilation

Question 13

Which one of the following is MISMATCHED?
Part1: trachea–hyaline cartilage C-shaped incomplete rings
Part2: trachea–respiratory epithelium
Part3: bronchi–hyaline cartilage as irregular plates
Part4: bronchi–pseudostratified epithelium with Clara cells
Part5: bronchioles–lacks hyaline cartilage

Answer 13

Part4: bronchi–pseudostratified epithelium with Clara cells

Question 14

Inhibiting the secretion of cholecystokinin is best described by which one of the following?
Part1: stimulate gallbladder contraction
Part2: stimulate gastric motility
Part3: stimulate HCl secretion by parietal cells
Part4: stimulate pancreatic enzyme secretion
Part5: is stimulated by amino acids in the stomach

Answer 14

Part2: stimulate gastric motility

Question 15

Concerning HCl secretion, all the following are true EXCEPT?
Part1: It involves active transport of Cl- from oxyntic cells into interstitial fluid and bicarbonate ions in
the opposite direction
Part2: It involves active transport of H+ from oxyntic cells into the gastric lumen and K- in the opposite
direction
Part3: It involves energy derived from ATP breakdown
Part4: It involves formation of carbonic acid
Part5: It’s stimulated by gastrin, acetylcholine and histamine

Answer 15

Part1: It involves active transport of Cl- from oxyntic cells into interstitial fluid and bicarbonate ions in
the opposite direction

Question 16

Why was the DNase treatment used by Avery and colleagues an important step?
Part1: This allowed them to demonstrate that mixing rough cells with DNA prevents transformation
Part2: This allowed them to demonstrate that removing the DNA prevents transformation
Part3: This allowed them to demonstrate that RNA was not the responsible for transformation
Part4: This allowed them to isolate pure DNA samples
Part5: This allowed them to isolate pure protein samples

Answer 16

Part2: This allowed them to demonstrate that removing the DNA prevents transformation

Question 17

Which one of the following is the best explanation for Okazaki fragments?
Part1: DNA polymerase can only synthesize 1000-2000 bonds before it falls off the strand
Part2: DNA polymerase can only synthesise new DNA in the 5’-3’ direction which requires a free 3’ OH group
Part3: DNA polymerase must stop to proof-read every 1000-2000 nucleotides
Part4: All of these are accurate statements
Part5: Only options two and three are correct

Answer 17

Part2: DNA polymerase can only synthesise new DNA in the 5’-3’ direction which requires a free 3’ OH group

Question 18

Which one of the following actions about RNA polymerase and DNA polymerase is correct?
Part1: RNA polymerase copies a RNA template, and DNA polymerase copies a DNA template
Part2: RNA polymerase binds to single-stranded DNA, and DNA polymerase binds to double-stranded DNA
Part3: RNA polymerase is much more accurate than DNA polymerase
Part4: RNA polymerase requires the Transcription Initiation Complex to initiate RNA synthesis, and DNA
polymerase requires a primer to initiate DNA synthesis
Part5: RNA polymerase synthesises in a 3’-5’ direction while DNA polymerase synthesises in a 5’-3’ direction

Answer 18

Part4: RNA polymerase requires the Transcription Initiation Complex to initiate RNA synthesis, and DNA
polymerase requires a primer to initiate DNA synthesis

Question 19

Promoter are regions of short nucleotide sequences that
(select one of the following)
Part1: act as binding sites for RNA polymerase and the transcription initiation complex
Part2: are found immediately upstream of the translation start site
Part3: contain the GGATGAT box
Part4: regulate the efficiency of transcription termination
Part5: regulate the initiation of translation

Answer 19

Part1: act as binding sites for RNA polymerase and the transcription initiation complex

Question 20

Which one of the following statements about Histones is correct?
Part1: Histones are found attached to ribosomes in the cytoplasm
Part2: Histones have protruding tails in nucleosomes which are highly conserved
Part3: Histones have protruding tails in nucleosomes which are highly variable
Part4: Histone tails are attached by RNA polymerase II before transcription
Part5: Histone tails associate with the major groove of DNA

Answer 20

Part2: Histones have protruding tails in nucleosomes which are highly conserved

Question 21

Regarding genes and chromosomes, which one of the following is correct?
Part1: a gene with the chromosomal map position 9q34.1 is on the short arm of chromosome 9
Part2: alleles are examples of linked genes
Part3: chromosome 1 is the smallest human autosome
Part4: in G2 stage of the cell cycle a human chromosome contains one linear ds DNA molecule
Part5: the pseudoautosomal region of the X chromosome does not undergo X inactivati

Answer 21

Part5: the pseudoautosomal region of the X chromosome does not undergo X inactivation

Question 22

Which one of the following best describes the inheritance of the non-lethal single gene disorder
achondroplasia which is autosomal and dominant?
Part1: If a family has two affected parents, all the children must be heterozygous carriers
Part2: If a family has two affected parents, all the children must suffer from the disorder
Part3: More girls than boys suffer from the disorder
Part4: Only individuals with two mutated copies of the gene suffer from the disorder
Part5: Two unaffected parents can have an affected child due to new mutation

Answer 22

Part5: Two unaffected parents can have an affected child due to new mutation