BIOL2103 Biological Sciences Laboratory course
2014-2015 Semester 2
Final Exam
*** Disclaimer: This sample paper is for reference only. Actual questions in
exams may differ in terms of format, content, level of difficulty, etc. The
accuracy of the content provided is not guaranteed. Please be aware that no one
is responsible for any mistakes or omissions to any information given.
There are 15 questions for each section, each question carries 3 marks. More than one
choices can be chosen for each question.
Section A
1. Maxam and Gilbert Chemical method:
(a) 5’ end of the single-stranded DNA is labelled with 32P.
TFTFT
(b) 3’ end of the single-stranded DNA is labelled with 32P.
(c) The four reactions are “A+G”, “T+C”, “C” and “G” reaction.
(d) The four reactions are “A+T”, “C+G”, “C” and “G” reaction.
(e) Electrophoresis is required.
2. Sanger Dideoxy method:
(a) DNA is 32P-labelled. T (primer DNA) F T
(b) dNTPs are 32P-labelled.
(c) Four separate reactions are required.
3. Automated sequencing with dye-terminators:
(a) Four separate reactions are required.
FT
(b) ddNTPs are fluorescently dyed.
4. Pyrosequencing:
(a) Unincorporated NTPs are degraded by ATP sulfurylase. FTTF
(b) PPi is released when dNTPs are incorporated to the primer.
(c) ATP sulfurylase changes PPi into ATP in the presence of APS
(d) Apyrase is used to oxidize luciferin into oxyluciferin.
5. The density of a liquid is 2g/ml. What method(s) can be used to measure 10 ml of
the liquid?
(a) Conical flask
(b) Measuring cylinder
(c) Glass pipette
(d) Weigh 20g of it by weighting balance
(e) Weigh 5g of it by weighing balance
6. Which shows the presence of pure DNA?
(a) I0 = I T F FF F
(b) I > I0
(c) I0> I
(d) T>1
(e) T<1
7. The pre-wet of pipette is required when transferring:
(a) All liquids
(b) High viscosity liquid
(c) Liquid < 10 microliter
8. Restriction enzyme:
TTFTF
(a) Bacteria produce its methylating enzyme.
(b) Base A is methylased.
(c) Base T is methylased.
(d) Base C is methylased.
(e) Base G is methylased.
9. Isochizomer and neoschizomers
(a) Isochizomers are isolated from different strains of bacteria.
(b) SmaI and XmaI are neoschizomers which recognise the same sequence and
cleave at a different site.
TTFFT
(c) SmaI and XmaI are neoschizomers which recognise the same sequence and
cleave at the same site.
(d) SphI and BbuI are isoschizomers which recognise the same sequence and
cleave at a different site.
(e) SphI and BbuI are isoschizomers which recognise the same sequence and
cleave at the same site.
10.
Restriction enzyme RE1 RE2 RE1+2
Band size 6350 5960 4350
2610 3000 2000
1000
Y
(a) The DNA plasmid has two RE1 sites. TTTTT
(b) The DNA plasmid has two RE2 sites.
(c) The site of RE2 is between the two sites of RE1.
(d) The site of RE1 is between the two sites of RE2.
(e) Y equals 1610.
11. RNA isolation:
(a) Acidic phenol and chloroform partition RNA into the aqueous solution in
centrifugation.
(b) Acidic phenol and chloroform partition protein into the aqueous solution
centrifugation.
(c) Guanidine isothiocynate denature proteins. TFTTF
(d) DEPC destroy RNase activity.
(e) DEPC destroy protease activity.
Section B
1. Which of the following bacteria is/ are in rod shape?
(a) Escherichia coli TTFTF
(b) Bacillus subtilis
(c) Staphylococcus epidermidis
(d) Pseudomonas aeruginosa
(e) Saccharomyces cerevisiae
2. Why heat fixation is used?
(a) To kill the bacteria.
(b) To fix the bacteria on the slide.
TTF
(c) To preserve cellular substructure.
3. Light microscope is used for:
(a) Bacteria identification
(b) Virus identification TFTTF
(c) Fungus identification
(d) Morphology
(e) Subcellular structure
4. Which of the following is included in the lens and observe stage of a microscope?
(a) Objective lens
(b) Ocular lens 文字
(c) Aperture diaphragm
(d) Field diaphragm
(e) Condenser
5. Which of the following is included in the light source of a microscope?
(a) Objective lens
(b) Ocular lens
(c) Aperture diaphragm
(d) Field diaphragm
(e) Condenser
6. The clarity of an microscopic image is described as:
(a) Resolution
(b) Resolving power
TT
(c) Magnification
(d) Numerical aperture
(e) Working distance.
7. How to describe cell morphology
(a) Texture, elevation
(b) Colour, shape
8. The growth of bacteria should be measured at:
(a) Log phase
(b) Lag phase
TFFFT
(c) Stationary phase
(d) Death phase
(e) Exponential phase
9. A student obtain stacks of bacteria colonies in all three phases after streaking
plates. What is/ are the possible reason(s)?
Section C
1. For Isopycnic centrifugation, the principle of separation is:
(a) size
F
(b) charge
F
(c) density T
F
(d) affinity F
(e) shape
2. For differential centrifugation, the sedimentation rate is affected by:
(a) density
(b) size TTFTT
(c) charge
(d) radius of centrifugation
(e) speed of centrifugation
3. Substance A and B have the same density, but A has a diameter 10 times larger
than that of B. What method(s) can be used to separate A and B?
(a) Differential centrifugation
(b) Rate zonal centrifugation TTFFFF
(c) Isopycnic centrifugation
(d) SDS-PAGE
(e) Western Blot
(f) Isoelectric focusing
4. In differential centrifugation, A (density = 2 g/ml) is centrifuged at 1000rpm. A
takes 1 hour to move from bottom to top of the gel. B has the same density and
size as A, what is the pelleting time for B?
(a) 15 minute
(b) 30 minute
(c) 1 hour
(d) 2 hour
(e) Insufficient information to calculate the pelleting time
5. Which of the following gradient material(s) can be used to separate blood cells?
(a) Sucrose
(b) Ficoll
(c) Percoll F TTFF
(d) Cesium Chloride
(e) Cesium trifluoroacetate
6. What information can you get from 2D-Western Blot?
(a) Molecular weight
TTT
(b) Concentration
(c) Presence of protein
7. Difference between rate zonal centrifugation and isopycnic centrifugation
(a) Both use shallow density gradient.
FTF
(b) Sample is layered on top of the pre-formed density gradient for both
centrifugation.
(c) They use the same principle for separating biomolecules.
8. Which of the following about antibody is correct?
(a) It has 2 light and 2 heavy chains. T
(b) In pregnancy test, the presence of fixed secondary antibody is a positive
control to detect coloured anti-hCG antibody. T
(c) In pregnancy test, the presence of fixed anti-hCG antibody is a positive control
to detect coloured anti-hCG antibody. F
(d) In pregnancy test, positive signal is shown by a sandwich of coloured anti-
T
hCG antibody, hCG and fixed anti-hCG antibody.
(e) In pregnancy test, positive signal is shown by a sandwich of coloured anti-
F
hCG antibody, hCG and fixed secondary antibody.
9. In stacking gel of discontinuous buffer system in SDS-PAGE:
(a) Glycine is the leading ion.
(b) There is a discontinuous voltage gradient.
(c) Protein has a higher mobility than glycine ion.
F,T, T,T,F,F
(d) Glycine has no net charge.
(e) Protein has no net charge.
(f) Chloride has no net charge.
10. In separating gel of discontinuous buffer system in SDS-PAGE:
(a) Protein is the leading ion. F, T, F, F, F,F
(b) There is a discontinuous voltage gradient.
(c) Protein has a higher mobility than glycine ion.
(d) Glycine has no net charge.
(e) Protein has no net charge.
(f) Chloride has no net charge.
11. For isoelectric focusing
(a) Protein change from positive to negative when moving towards the negative
electrode.
(b) The charge of protein depends on the location.
,T,T,F
(c) Proteins are distributed according to pI values.
(d) Proteins are distributed according to ion strength.
