GEN602S - GENETICS -1ST OPP - NOVEMBER 2023


GEN602S - GENETICS -1ST OPP - NOVEMBER 2023



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nAmlBIA UnlVERSITY
OF SCIEnCE AnDTECHnOLOGY
Facultyof Health,Natural
ResourceasndApplied
Sciences
Schoolof Natural and Applied
Sciences
Departmentof Biology,
ChemistryandPhysics
13Jackson Kaujeua Street
Private Bag 13388
Windhoek
NAMIBIA
T: •264 612072012
F: +264 61207 9012
E: dbcp@nust.na
W: www.nust.na
QUALi FICATION : BACHELOR OF SCIENCE
QUALIFICATION CODE: 07BOSC
LEVEL: 6
COURSE:GENETICS
COURSECODE: GEN602S
DATE: NOVEMBER 2023
SESSION: 1
DURATION: 3 HOURS
MARKS: 100
EXAMINER:
MODERATOR:
FIRST OPPORTUNITY: QUESTION PAPER
Prof Edosa Omoregie
Dr Jeya Kennedy
INSTRUCTIONS
1. Answer all questions on the separate answer sheet.
2. Please write neatly and legibly.
3. Do not use the left-side margin of the exam paper. This must be allowed for the
examiner.
4. No books, notes and other additional aids are allowed.
5. Mark all answers clearly with their respective question numbers.
PERMISSIBLE MATERIALS:
1. Non-Programmable Calculator
ATTACHMENTS
None
This paper consists of 5 pages including this front page

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SECTION A: MULTIPLE CHOICE
[20 MARKS]
QUESTION 1: MULTIPLE CHOICE QUESTIONS
(20 MARKS]
Evaluate the statements in each numbered section and select the most appropriate answer
or from the given possibilities. Fill in the appropriate letter next to the number of the correct
statement/phrase on your ANSWERSHEET.
[20]
1.1. Division of the cytoplasm of a eukaryotic cell during mitosis is called?
A. karyokinesis
8. plamsokinesis
C. diakinesis
D. cytokinesis
1.2. Synapsis of the homologous chromosomes in the eukaryotic cell occurs during which
of the following division phases?
A. anaphase I
8. telophase I
C. prophase I
D. prophase II
1.3. In a cross between two black Labrador dogs, the phenotype ratio of the offspring is 9
black puppies to 3 chocolate puppies to 4 yellow puppies; this is an example of?
A. partial recessiveness
8. incomplete penetrance
C. incomplete dominance
D. epistasis
1.4 Mitotic cell division results in two cells that have:
A. n chromosomes that are genetically identical
8. n chromosomes that are genetically different
C. 2n chromosomes that are genetically identical
D. 2n chromosomes that are genetically different
1.5. Which of the following is an autosomal recessive trait?
A. Duchenne muscular dystrophy
8. Lesch-Nyhan syndrome
C. Marfan syndrome
D. Cystic Fibrosis
1.6. Which of the following terms best describes the replication of DNA?
A. constitutive
B. conservative
C. semi-conservative
D. semi-constitutive
Genetics (GEN602S)
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1.7. In DNA molecule, which of the following bonds is true?
A. the [G] = [C]
B. the (G+C] = [A+T]
C. the (G] = (A]
D. none of the above are true
1.8. During DNA synthesis, the addition of a new nucleotide to a newly formed DNA strand
always proceeds in which direction?
A. from the promoter
B. in either direction
C. in the 3' to 5' direction
D. in the 5' to 3' direction
1.9. Which of the following statements is true on the role of the enzyme ligase during the
replication of a DNA molecule?
A. remove the RNA primer
B. to stabilise the single-stranded structure
C. to link Okazaki fragments together
D. to unwind the original DNA molecule
1.10.
Which of the following statements about transposons during gene recombination is
not true?
A. during transposition a short sequence of target DNA is duplicated, and the
transposon is inserted between the directly repeated target sequences
B. some transposons insert into almost any target DNA sequence
C. the actions of transposases go on indefinitely without interruption
D. transposons are important genetic elements because they cause mediate genomic
rearrangement
1.11.
In transcription, RNA polymerase binds at?
A. a promoter
B. an operator
C. the centromere
D. an enhancer
1.12.
Which of the following statements best describes the Central Dogma theory in genetics?
A. the pattern of genetic information flow in the cell
B. the pattern of chromosomal inheritance in populations
C. the role of mutations in disease
D. the role of promoters
1.13.
Which statements below best describe the role of the enzyme resolvases in genetic
recombination?
A. catalyses transposon movement to another part of the genome
B. catalyses transposon formation in gene recombination
C. represses the actio.n of transposase
D. speeds up the action of transposase
Genetics (GEN6025)
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1.14.
Which of the following blood genotypes belongs to an individual who is regarded as a
universal blood recipient?
A. 1A1A
B. 1A10
(. IAIB
D. 1°1°
1.15.
Which of the following autosomal
suffering from Down Syndrome?
A. Trisorny 18
B. Trisorny 21
C. X rnonosomy
D. Trisomy 15
chromosome
conditions
is for an individual
1.16.
Which of the following is the optimum temperature for thermostable
polymerase of Taq polymerase during the PCR experimental step of
denaturation?
A. 94- 98°C
s. 100 - 1os 0 c
C. 45 - so 0 c
D. 7S-8o 0 c
DNA
DNA
1.17.
Which of the following is an assumption for Hardy-Weinberg equilibrium?
A. no epistasis
B. no dominance
C. no crossing-over
D. no mutation
1.18.
Which of the following chromosome number is a pentasomy?
A. 2n- 2
B. 2n + 2
C. 2n -1
D. 2n + 3
1.19.
A human with Patau's syndrome would represent which of the following chromosomal
conditions?
A. diploid condition
B. euploid condition
C. aneuploid condition
D. haploid condition
1.20.
Which factors alter allele frequencies that bring about the most evolutionary change?
A. Indiscriminating intraspecific mating
B. Inbreeding
C. DNA replication
D. Genetic drift
Genetics (GEN602S)
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SECTION B: ESSAY QUESTIONS
Please answer ANY FOURof the questions in this section.
[80 MARKS]
QUESTION 2
2.1. Using suitable molecular diagrams, discuss the structure of the DNA double helix,
including its subunits and how they are bonded together, indicating the antiparallel
arrangements of the polynucleotide strands.
(15)
2.2. Explain the concept of epistasis in genetics. Give an example of a genetic disease
resulting from this concept.
(5)
QUESTION 3
3.1. With suitable diagrams, briefly describe the process of mitotic division in a eukaryotic
cell, emphasising the changes on the chromosome.
(12)
3.2. Briefly differentiate gene mutation from chromosomal mutation.
(2)
3.3. With the aid of illustrations, discuss the substitution, insertion, and deletion process
in gene mutation.
(6)
QUESTION 4
4.1. Describe the synthesis of new DNA and explain the roles of the various enzymes
involved in synthesising new DNA strands from the parent DNA strand.
(10)
4.2. Briefly explain the molecular structure of transfer RNA and highlight the main
structural differences between RNA and DNA molecules.
(8)
4.3. Briefly explain the primary function of ribosomal RNA.
(2)
QUESTION 5
With schematic diagrams, briefly explain the process of gene expression in
eukaryotes and the role of the enzymes involved in the process.
(20)
QUESTION 6
6.1. Explain the process of nonreplicative transposition and how it differs from replicative
transposition. Use illustrations to show the differences.
(10)
6.2. Discussthe consequences of transposition events within a given population.
(6)
6.3. Explain the term microevolution based on genetic principles.
(4)
END OF QUESTION PAPER
Genetics (GEN602S)
1" Opportunity- November 2023
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