Multiple choice question for engineering
Set 1
1. Out of the following, cholesterol does not serve as a precursor for which compounds?
a) Vitamin D
b) Sex hormones
c) Bile salts
d) Bile pigments
Answer
Answer: d [Reason:] Cholesterol serves as a precursor for the biosynthesis of steroid molecules, bile acids and vitamin D.
2. Which of the following is a sphingophospholipid?
a) Lecithin
b) Sphingomyelin
c) Plasmolegen
d) Cardiolipin
Answer
Answer: b [Reason:] Lecithin, plasmolegen and cardiolipin are glycerophospholipids.
3. Which of the following glycerophospholid acts as a lipotropic agent?
a) Cardiolipin
b) Phosphatidylserine
c) Phosphatidylinositol
d) Phosphatidylcholine
Answer
Answer: d [Reason:] Only phosphatidylcholine acts as a lipotropic agent.
4. Which of the following phospholipids is a component of inner mitochondrial membrane?
a) Plasmologen
b) Cephalin
c) Lecithin
d) Cardiolipin
Answer
Answer: d [Reason:] Cardiolipin is an essential component of inner mitochondrial membrane.
5. In which of the following glycerophospholipids two phosphatidic acids share a single glycerol?
a) Cardiolipin
b) Phosphatidylserine
c) Phosphatidylinositol
d) Phosphatidylcholine
Answer
Answer: a [Reason:] In cardiolipin, two phosphatidic acids share a single glycerol.
6. Platelet activating factor stimulates the release of which of the following compounds?
a) Vasopressin
b) Serotonin
c) Adrenaline
d) Cortisol
Answer
Answer: b [Reason:] Platelet activating factor stimulates the release of serotonin.
7. Which of the following group of membrane lipids predominate in plant cells?
a) Galactolipids
b) Sphingolipids
c) Glycerophospholipids
d) Archaebacterial ether lipids
Answer
Answer: a [Reason:] Galactolipids are the lipids predominant in the chloroplasts of plants.
8. Which of the following membrane lipids have a direct glycosidic linkage between the head-group sugar and the backbone glycerol?
a) Glycolipids
b) Phospholipids
c) Sphingolipids
d) Ether lipids
Answer
Answer: a [Reason:] Glycolipids have a direct glycosidic linkage between the head-group sugar and the backbone glycerol.
9. The backbone of phospholipids is
a) L-glycerol 1-phosphate
b) L-glycerol 3-phosphate
c) D-glycerol 3-phosphate
d) sn-glycerol 1-phosphate
Answer
Answer: b [Reason:] L-glycerol 3-phosphate or D-glycerol 1-phosphate or sn-glycerol 3-phosphate is the backbone of phospholipids.
10. What is the head-group alcohol in plasmolegen and platelet-activating factor?
a) Alkene
b) Choline
c) Alkane
d) Acetic acid
Answer
Answer: b [Reason:] Choline is the head-group alcohol in plasmolegen and platelet-activating factor.
11. Which of the following does not contain glycerol?
a) Glycerophospholipids
b) Galactolipids
c) Sphingolipids
d) Triacylglycerols
Answer
Answer: c [Reason:] Sphingolipids contain sphingosine instead of glycerol.
Set 2
1. The DNA threads which appear inside the nucleus at the time of cell division
a) Spindle fibers
b) Centrioles
c) Asters
d) Chromosomes
Answer
Answer: d [Reason:] Chromosome is a thread-like DNA structure carrying genetic information in the form of genes.
2. Which of the following is not a major class of chromatin proteins?
a) Histones
b) Topoisomerases
c) SMC proteins
d) Cohesins
Answer
Answer: d [Reason:] Cohesins are the proteins in SMC family.
3. Which of the following plays a substantial role in linking together sister chromatids immediately after replication?
a) Cohesins
b) Condensins
c) Histones
d) Topoisomerases
Answer
Answer: a [Reason:] The cohesins play a substantial role in linking together sister chromatids immediately after replication and keeping them together as the chromosomes condense to metaphase.
4. Which of the following are essential to the condensation of chromosomes as cells enter mitosis?
a) Cohesins
b) Condensins
c) Histones
d) Topoisomerases
Answer
Answer: b [Reason:] Cohesins are important immediately after replication.
5. Chromatin is composed of
a) DNA
b) DNA and proteins
c) DNA, RNA and proteins
d) None
Answer
Answer: c [Reason:] DNA + histones combination is termed as chromatin.
6. Which of the following histones bind to linker DNA?
a) H1
b) H2A
c) H2B
d) H3
Answer
Answer: a [Reason:] The bead of each nucleosome contains eight histone molecules: two copies each of H2A, H2B, H3 and H4.
7. Which of the following has beads on a string structure?
a) Chromosomes
b) Chromatin
c) Nucleosomes
d) Heterochromatin
Answer
Answer: c [Reason:] DNA winds around histone proteins forming nucleosomes: the beads on a string structure.
8. Which of the following histones shows more sequence similarity among eukaryotic species?
a) H1
b) H2A
c) H2B
d) H3
Answer
Answer: d [Reason:] The H3 histones are nearly identical in amino acid sequence in all eukaryotes, as are the H4 histones.
9. The sister chromatids separate at
a) Prophase
b) Metaphase
c) Telophase
d) Anaphase
Answer
Answer: d [Reason:] During anaphase, each chromosomal pair is separated into two identical and independent chromosomes.
10. Cellular DNA is uncondensed throughout
a) Prophase
b) Interphase
c) Telophase
d) Anaphase
Answer
Answer: b [Reason:] During interphase, the cell’s DNA is not condensed.
Set 3
1. A set of overlapping DNA segments that together represent a consensus region of DNA is
a) Expressed sequence tag
b) Sequence tagged site
c) Contig
d) YAC
Answer
Answer: c [Reason:] Sequence tagged site is a short DNA sequence having single occurrence in genome.
Expressed sequence tag is a short sub-sequence of a cDNA sequence.
YAC is a linear DNA molecule.
2. Which of the following statements is false?
a) BAC is a circular DNA molecule
b) YAC is a linear DNA molecule
c) Taql is a DNA polymerase
d) BAC is a linear DNA molecule
Answer
Answer: d [Reason:] BAC is a circular DNA molecule.
3. Which of the following is not denatured by heating steps during PCR?
a) DNA pol
b) RNA pol
c) Restriction enzymes
d) DNA ligase
Answer
Answer: a [Reason:] DNA polymerase, Taq is thermo stable, so it is not denatured by heating steps during PCR.
4. Which of the following statements regarding DNA fingerprinting is false?
a) DNA fingerprinting cannot be used for paternity testing
b) DNA profile using STR (short terminal repeats) is unique to an individual
c) PCR is used for DNA profiling
d) Forensic analysis makes use of SNPs (single nucleotide polymorphisms) in coding sequences to distinguish between individuals
Answer
Answer: a [Reason:] DNA fingerprinting is used for paternity testing.
5. How are expression vectors useful?
a) To produce protein products
b) Used for genomic libraries
c) Used for chromosome synthesis
d) Used for finger printing
Answer
Answer: a [Reason:] Expression vectors are helpful for the expression of genes.
6. Who was the first person to develop DNA finger printing?
a) David Suzuki
b) Khorana
c) Alec Jaffreys
d) Gilbert
Answer
Answer: c [Reason:] Alec Jaffreys was the first person to develop DNA finger printing.
7. Southern blotting technique is used in
a) Monoclonal antibody production
b) In vitro culture
c) Genetic finger printing
d) Polymerase chain reaction
Answer
Answer: c [Reason:] Applications of southern blotting:
In RFLP, forensics, diagnosis of HIV etc.
8. Electrophoresis helps to separate
a) DNA segments
b) Cells from DNA
c) Tissues
d) RNA from DNA
Answer
Answer: a [Reason:] In electrophoresis, DNA fragments are separated according to their size.
9. During DNA profiling, DNA nucleotides hybridized with probe can be detected through
a) Electrophoresis
b) Polymerase chain reaction
c) Autoradiography
d) Hybridoma
Answer
Answer: c [Reason:] Autoradiography is a detection method in hybridization.
10. Which of the following term is associated with DNA finger printing?
a) Hybridoma
b) Site specific mutagenesis
c) Shotgun cloning
d) RFLP
Answer
Answer: d [Reason:] RFLP technique is preferred in forensic laboratories to identify the suspects.
11. Recombinant DNA construction involves
a) Cleaving DNA with restriction endonuclease and joining with ligase
b) Cleaving DNA with ligase and joining with endonuclease
c) Cleaving and joining DNA with restriction endonuclease
d) Cleaving DNA with restriction endonuclease and joining with polymerase
Answer
Answer: a [Reason:] Restriction enzymes cleave plasmid vector and then DNA ligase joins foreign DNA with cloning vector.
Set 4
1. A) CuSO4 + 5H2 O CuSO4.5H2 O
B) PCl3 + 3H2 O H3 PO3 + 3HCl
The processes A and B are respectively
a) Hydration and dehydration
b) Hydration and hydrolysis
c) Hydrolysis and hydrolysis
d) Hydration and hydration
Answer
Answer: b [Reason:] Process A involves absorption of water and B involves double decomposition reaction.
2. Which of the following is not a condensation reaction?
a) ADP + inorganic phosphate ATP + H2O
b) R-OH + inorganic phosphate phosphate ester + H2 O
c) R-COOH + inorganic phosphate Acyl phosphate + H2 O
d) 6CO2 + 6 H2 O C6 H12 O6 + 6CO2
Answer
Answer: d [Reason:] Condensation reaction involves elimination of water molecules.
3. Which of the following is the correct equation?
a) CO2 + H2 O H2 CO3
b) CO2 + H2 O HCO3
c) CO2 + H2 O H3 CO3
d) CO2 + H2 O H2 CO2
Answer
Answer: a [Reason:] The correct balanced equation is CO2 + H2 O H2 CO3. Carbondioxide reacts with water to give carbonic acid.
4. Consider the following reaction, in the presence of light
2H2 O + 2X O2 + 2XH2
Which of the following statements is true?
a) X is electron-accepting specie
b) X is electron-donating specie
c) Water is an electron acceptor
d) Water neither donates nor accepts any electron
Answer
Answer: a [Reason:] In this oxidation reduction sequence, water serves as the electron donor and X serves as an electron acceptor.
5. Hydrolysis reactions are catalyzed by enzymes called
a) Oxidoreductase
b) Ligase
c) Hydrolase
d) Isomerase
Answer
Answer: c [Reason:] Hydrolases, which catalyze hydrolysis reaction involve in food decomposition and in digestion process.
6. What does it mean when we say that water acts as a “heat buffer”?
a) It keeps the temperature of an organism relatively constant as the temperature of the surroundings fluctuates.
b) It increases the temperature of an organism as the temperature of the surroundings increases
c) It decreases the temperature of an organism as the temperature of the surroundings increases
d) It increases the temperature of an organism as the temperature of the surroundings decreases
Answer
Answer: a [Reason:] Water has a high specific heat capacity, it is hard to increase or decrease the water temperature which requires a lot of heat energy and therefore water acts as a heat buffer.
7. Which of the following does not react with water?
a) Barium
b) Calcium
c) Beryllium
d) Strontium
Answer
Answer: c [Reason:] Be is the only alkaline earth metal which does not react with water.
8. What trend does the reactivity of group II elements follow with water?
a) Increases down the group
b) Decreases down the group
c) Does not follow any particular trend
d) No reaction
Answer
Answer: a [Reason:] As we descend down the group, losing of electrons from the outer orbit of an atom becomes easy.
9. Which among the following statements is true about the following chemical reaction?
3Fe(s) + 4H2 O → Fe3 O4 (s) + 4H2
a) Iron metal is getting reduced.
b) Water is acting as a reducing agent
c) Water is acting as an oxidizing agent
d) Water is getting oxidized
Answer
Answer: c [Reason:] Water is getting reduced and it oxidizes iron metal, thus acting as an oxidizing agent.
10. Identify the products formed in the following reaction
CH3 COOCH3 + H2 O → A + B
a) CH3 COOH and CH3 OH
b) CH3 COOOH and CH4
c) CO2 and C2 H6
d) No reaction
Answer
Answer: a [Reason:] Ester Hydrolysis
CH3 COOCH3 + H2 O → CH3 COOH + CH3 OH.
Set 5
1. What makes water a liquid at room temperature?
a) Hydrogen bonds between water molecules
b) Covalent bonding
c) Noncovalent interactions
d) Van der Waals forces of attraction
Answer
Answer: a [Reason:] Hydrogen bonds between water molecules provide the cohesive forces that make water a liquid at room temperature.
2. ΔG is negative for which of the following processes?
a) Melting of ice and evaporation of water
b) Oxidation of nitrogen
c) Oxidation of gold
d) Burning of chlorine
Answer
Answer: a [Reason:] The Gibb’s free energy change (ΔG) must have a negative value for a process to occur spontaneously.
Melting of ice and evaporation of water are the two spontaneous processes at room temperature.
3. ΔH is positive for which of the following processes?
a) Oxidation of nitrogen
b) Melting of ice and evaporation of water
c) Oxidation of gold
d) Burning of chlorine
Answer
Answer: b [Reason:] Enthalpy change (ΔH) is positive for endothermic reactions, the reactions which involves absorption of energy.
Melting of ice and evaporation of water involves absorption of energy.
4. What is the factor that is responsible for salts like NaCl to dissolve in water easily?
a) Decrease in entropy
b) Increase in entropy
c) Increase in enthalpy
d) Decrease in enthalpy
Answer
Answer: b [Reason:] As a salt such as NaCl dissolves , the 〖Na〗^+ and 〖Cl〗^- ions leaves the crystal lattice resulting in increase in entropy(randomness) of the system which is largely responsible for the ease of dissolving salts such as NaCl in water.
5. Heat of vaporization of water is
a) 2260 J/g
b) 2260 kJ/g
c) 1260 J/g
d) 1260 kJ/g
Answer
Answer: a [Reason:] The amount of energy needed to change one gram of water to its vapor form at constant temperature is 2260 J/g.
6. The bond dissociation energy of hydrogen bonds in a water molecule is
a) 470 kJ/mole
b) 470 J/mole
c) 23 kJ/mole
d) 23 J/mole
Answer
Answer: c [Reason:] The energy required to break the hydrogen bonds (H-H) in water molecule is 23 kJ/mole.
7. The bond dissociation energy of O-H bond in a water molecule is
a) 23 kJ/mole
b) 470 kJ/mole
c) 470 J/mole
d) 23 J/mole
Answer
Answer: b [Reason:] The energy required to break O-H bond in a water molecule is more than that required for breaking hydrogen bond, which is 470 kJ/mole.
8. Which of the following is a hypertonic solution?
a) Oceans
b) Freshwater habitats
c) 0.45% sodium chloride
d) Red blood cells placed in fresh water
Answer
Answer: a [Reason:] The sea water or oceans are hypertonic to the extracellular fluid of many of the marine organisms. These marine organisms overcome the problem of hyper tonicity by expelling the salt water continuously.
9. Which of the following is a hypotonic solution?
a) 10% dextrose in water
b) 0.45% sodium chloride
c) 5% dextrose in 0.9% sodium chloride
d) Oceans
Answer
Answer: b [Reason:] 0.9% normal saline is isotonic and half of 0.9 = 0.45% makes the solution more diluted (contains more water), therefore the solution is hypotonic.
10. Which of the following is an isotonic solution?
a) 0.9% sodium chloride
b) 0.45% sodium chloride
c) Oceans
d) 10% dextrose in water
Answer
Answer: a [Reason:] The normal saline solution, 0.9% NaCl has the same salt concentration as the surrounding blood cells.