Copy and Edit

Biochemistry MCQs- MAY 12

Description

Quiz on Biochemistry MCQs- MAY 12, created by MatthewEllis96 on 02/02/2015.
MatthewEllis96
Quiz by MatthewEllis96, updated more than 1 year ago
MatthewEllis96
Created by MatthewEllis96 over 9 years ago
49
0
0

Resource summary

Question 1

Question
The glycolytic pathway in dinosaurs
Answer
  • Was likely to be completely different to modern day animals, because every organism has different metabolic pathways
  • Was likely to be completely different to modern day organisms because they eat different types of food
  • Was likely to be similar or identical to modern day organisms, because metabolic pathways have been highly conserved through evolution
  • Is something we cannot make meaningful predictions about because we have no knowledge of how metabolism has evolved

Question 2

Question
In thin layer chromatography, ninhydrin can be used to stain which compounds?
Answer
  • Monosaccharides
  • Amino acids
  • Keto acids
  • All of the above

Question 3

Question
Which of the following lists contains the components of a phospholipid?
Answer
  • Choline, phosphate group, glycerol, fatty acids
  • Choline, phosphate group, glyceraldehyde, fatty acids
  • Carnitine, phosphate group, glycerol, amino acids
  • Carnitine, phosphate group, glyceraldehyde, amino acids

Question 4

Question
Testosterone belongs to which class of compounds?
Answer
  • Fats
  • Oils
  • Ketose monosaccharides
  • Sterols

Question 5

Question
Which of the following passes easily through phospholipid bilayers?
Answer
  • Chloride ions
  • ATP
  • Glucose 6-phosphate
  • Water

Question 6

Question
Peripheral membrane proteins
Answer
  • Pass through the cell membrane
  • Are non-covalently associated with integral membrane proteins
  • Are covalently linked to membrane lipids
  • Are always linked to sugars

Question 7

Question
Which of the following fatty acids is likely to have the highest melting temperature?
Answer
  • One with 14 carbon atoms and no double bonds
  • One with 14 carbon atoms and one double bond
  • One with 16 carbon atoms and no double bonds
  • One with 16 carbon atoms and one double bond

Question 8

Question
In the furanose ring form of β-D-fructose, how many of the carbon atoms are chiral?
Answer
  • 0
  • 2
  • 4
  • 6

Question 9

Question
Cellulose is a polymer of
Answer
  • α-D-glucose units only
  • β-D-glucose units only
  • α-D-glucose and β-D-fructose units
  • β-D-glucose and α-D-fructose units

Question 10

Question
In catabolic (degradative) reactions in humans, the most commonly used oxidising cofactors are
Answer
  • NAD+ and FAD
  • NADP+ and FAD
  • NADH and FADH2
  • NADPH and FADH2

Question 11

Question
Considering only the glycolytic pathway, what is the net gain in ATP molecules, per molecule of glucose processed?
Answer
  • 0
  • 1
  • 2
  • 4

Question 12

Question
Under anaerobic conditions, glycolysis in mammals can result in the compound lactose. Why?
Answer
  • To make ATP by substrate level phosphorylation
  • To regenerate NAD+
  • To make NADH for oxidative phosphorylation
  • To replenish Krebs’ (tricarboxylic acid) cycle intermediates

Question 13

Question
Which of the following statements about gluconeogenesis is TRUE?
Answer
  • Glucose is generated from the hydrolysis of phosphate from glucose 6-phosphate. No ATP is produced in this reaction.
  • Glucose is generated from the hydrolysis of phosphate from glucose 6-phosphate. One molecule of ATP is produced in this reaction.
  • In mammals, acetyl coenzyme A (AcCoA) can be a starting point.
  • The reactions are exactly the same as glycolysis, except in reverse.

Question 14

Question
Isomerisation of glucose 1-phosphate to glucose 6-phosphate occurs in
Answer
  • Glycolysis and gluconeogenesis
  • Glycogen synthesis and degradation
  • Glycolysis and the Leloir pathway
  • The Leloir pathway and glycogen degradation

Question 15

Question
In the Calvin cycle, carbon dioxide reacts with ribulose 1,5-bisphosphate. The first product(s) of this reaction is/are:
Answer
  • Two molecules of 3-phosphoglycerate
  • Two molecules of glyceraldehyde 3-phosphate
  • One molecule of glucose 6-phosphate
  • One molecule of fructose 6-phosphate

Question 16

Question
In Calvin’s experiments to identify the compounds in the Calvin cycle, the function of the hot ethanol was
Answer
  • To shield the algae from the heat of the lamps
  • To provide a source of carbon atoms for the algae
  • To kill the algae after a defined time point
  • To solublise the compounds in the algae

Question 17

Question
The main source of energy for sperm cells is
Answer
  • Glucose
  • Fatty acids
  • Glycerol
  • Fructose

Question 18

Question
The transition state in an enzyme-catalysed reaction:
Answer
  • Is always covalently associated to the enzyme.
  • Is never covalently associated to the enzyme.
  • Can never be observed experimentally.
  • Can often be similar in structure to potent enzyme inhibitors.

Question 19

Question
In enzyme catalysis, the term ‘approximation’ refers to:
Answer
  • A catalytic strategy that facilitates transition state stabilisation through formation of covalent bonds between a substrate and amino acid groups in the active site.
  • A catalytic strategy that facilitates transition state stabilisation through formation of hydrogen bonds and electrostatic interactions between a substrate and amino acid groups in the active site.
  • A catalytic strategy that facilitates transition state stabilisation through interaction with metal ions in the active site.
  • A catalytic strategy that facilitates transition state stabilisation through direct transfer of a proton to the substrate from an acidic amino acid group in the active site.

Question 20

Question
The Urea cycle:
Answer
  • Is completely located in the mitochondrial matrix – preventing the exposure of free ammonium to other components of the eukaryote cell.
  • Allows free ammonia obtained directly from de-amination of glutamate to be converted to urea – preventing the exposure of free ammonium to other components of the eukaryote cell.
  • Allows free ammonia obtained directly from de-amination of tryptophan to be converted to urea – preventing the exposure of free ammonium to other components of the eukaryote cell.
  • Is completely located in the cytoplasm of the cell – preventing the exposure of free ammonium to other components of the eukaryote cell.

Question 21

Question
Serine proteases:
Answer
  • Are proteases that hydrolyse polypeptides with serine in the F1 position
  • Are proteases that are found in the cytoplasm of all cells
  • Utilise a serine residue at the active site to facilitate substrate binding
  • Utilise a serine residue at the active site to facilitate cleavage of peptide bonds

Question 22

Question
Consider an enzyme that shows Michaelis-Menton kinetics where: vo = Vmax . [S] / (Km + [S]) If a substrate, S, is present at a concentration of 4 mM, and Km is 2 mM, the rate of reaction (vo) measured will be:
Answer
  • Half of Vmax
  • Two thirds of Vmax
  • Double Vmax
  • Three times Vmax

Question 23

Question
In acid-base catalysis:
Answer
  • An acidic- or basic- amino acid in the active site of an enzyme facilitates transition state formation by hydrogen abstraction from an appropriate substrate.
  • An acid- or basic- substrate in the active site of an enzyme facilitates transition state formation by hydrogen abstraction from a catalytic amino acid in the active site.
  • Both are correct.
  • Neither are correct.

Question 24

Question
The protein ubiquitin:
Answer
  • Can be covalently linked to proteins via the N-terminus glycine residue.
  • Is a polypeptide.
  • Is an essential component of eukaryote respiratory chains.
  • Can be covalently linked to proteins via isopeptide bond formation.

Question 25

Question
An oxyanion hole is:
Answer
  • A region of the enzyme active site that facilitates binding of positively charged substrates through their association with oxygen-containing amino-acid side chains in the enzyme.
  • A region of the enzyme active site that facilitates binding of negatively charged substrates through their association with oxygen-containing amino acid side chains in the enzyme.
  • A region of the active site that facilitates binding of positively charged oxygen containing groups present in a substrate.
  • A region of the active site that facilitates binding of negatively charged oxygen-containing groups present in a substrate.

Question 26

Question
If the ΔG°′ of the reaction Malate → Oxaloacetate is +30 kJ/mol, what will happen in the presence of malate dehydrogenase under standard conditions?
Answer
  • The reaction will proceed fast with the formation of the explosive products.
  • The reaction will not occur spontaneously.
  • The reaction will never reach equilibrium.
  • The reaction will proceed spontaneously from left to right.

Question 27

Question
Which of the following redox couple have the highest midpoint redox potential?
Answer
  • ubiquinol/ubiquinone
  • NADH/NAD+
  • H2O/½O2
  • ferrocytochrome c/ferricytochrome c

Question 28

Question
What is the source of energy for ATP synthesis in mitochondria?
Answer
  • AMP, ADP and inorganic phosphate
  • Gradient of Na+ across the inner mitochondrial membrane
  • Matrix fumarase and aconitase
  • None of the above

Question 29

Question
Which of the following cannot reduce mitochondrial respiratory chain in normal conditions?
Answer
  • NADH
  • Oxygen
  • FADH2
  • Ubiquinol

Question 30

Question
The oxygen molecules released into the air as a product of photosynthesis comes from:
Answer
  • Light quanta
  • Cytochome c oxidase
  • Carbon dioxide
  • Water

Question 31

Question
Production of lactic acid in anaerobic muscle cells is:
Answer
  • Caused by breakdown of glycogen
  • Caused by a buildup of AMP
  • Coupled to the recycling of NAD+ to NADH by lactate dehydrogenase when it oxidises pyruvate
  • Due to pyruvate being reduced by lactate dehydrogenase while it recycles NADH to NAD+

Question 32

Question
Phosphofructokinase-1 activity is:
Answer
  • Inhibited by fructose 2,6-bisphosphate
  • Inhibited by AMP
  • Inhibited by citrate
  • Stimulated by citrate

Question 33

Question
The Warburg effect:
Answer
  • Is the inhibition of glycolysis that occurs in anaerobic cells when exposed to oxygen
  • Is the continued use of anaerobic fermentation by cancer cells even in the presence of oxygen
  • Is caused by an over-active glycerol phosphate shuttle in cancer
  • Is due to the inhibition of phosphofructokinase-1 by AMP

Question 34

Question
Glycogen synthase activity is:
Answer
  • Inhibited by ATP
  • Stimulated by glucose 6-phosphate
  • Stimulated by fructose 1,6-bisphosphate
  • Inhibited by citrate

Question 35

Question
Phosphofructokinase-1 activity is:
Answer
  • Stimulated by citrate
  • Inhibited by AMP
  • Inhibited by citrate
  • Inhibited by fructose 2,6-bisphosphate

Question 36

Question
Which of the following is NOT true of Aldosterone?
Answer
  • It is a mineralocorticoid
  • It is a peptide hormone
  • It is a steroid hormone
  • It is released in response to angiotensin II

Question 37

Question
Calcitonin is a hormone that is released from:
Answer
  • The pituitary gland
  • The thyroid gland
  • The hypothalamus
  • The parathyroid gland

Question 38

Question
Which of the following is NOT a feature of metabolic pathways?
Answer
  • Sequential feedback inhibition
  • Common intermediate metabolites
  • The presence of aquaporins
  • End product inhibition

Question 39

Question
Which of the following is NOT true of the anabolic hormone insulin?
Answer
  • It increases glycogen synthesis
  • It increases fatty acid synthesis
  • It increases esterification of fatty acids
  • It increases protein breakdown (proteinolysis)

Question 40

Question
Which of the following has NOT been a commercial method for the synthesis of artificial human insulin?
Answer
  • Separate A- and B-chain synthesis in E. coli
  • Phage display in E. coli
  • Pro-insulin synthesis in E. coli
  • Biosynthesis in brewer’s yeast (Saccharomyces cerevisiae)
Show full summary Hide full summary

Want to create your own Quizzes for free with GoConqr? Learn more.

Similar

Epithelial tissue
Morgan Morgan
Hitler's Rise to Power
hanalou
An Inspector Calls - Themes
mhancoc3
Cell Parts & Genetics
Selam H
American West - Key Dates
Rachel I-J
Chemistry Regents - Bonding Theories and Polar Bonds Notes
Ali Kane
An Inspector Calls
Georgia 27
All AS Maths Equations/Calculations and Questions
natashaaaa
Biology -B2
Sian Griffiths
GRE Verbal Reasoning Vocabulary Flashcards 1
Sarah Egan
DEV I Part II
d owen
Browse Library