BSc. Life Sciences -II: Genetics -Mumbai-April 2019
MUMBAI UNIVERSITY
Subject: Life Sciences – II: Genetics.
Semester: 2
[Total Time: 2½ Hours ]
[Total Marks: 75 ]
N.B.: 1) Attempt all questions.
2) All questions carry equal marks.
3) Draw neat labeled diagrams wherever necessary
4) Use of log tables and non-programmable calculator is allowed.
5) For Q.2, Q.3, and Q.4 attempt A and B ORC and D4
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Q 1) Do as directed (Any fifteen) (15M)
1) Define Genotype.
2) _____________ genes are the genes which when mutated can result in the lethal phenotype.
3) The ratio for dominant epistasis is _____________ .
4) State true or false: Environmental Faciori influences expression of genes.
5) Define Dominant trait.
6) A cross between a homozygous dominant individual and a homozygous recessive individual will always result in a ______________ individual.
7) ABO blood type in humans is a characteristic due to multiple _______________ .
8) Define Transduction
9) State-true or false: In a HFr X F cross, the frequency of recombination is low
10) Give an term for an extra-chromosomal self-replicating circular DNA in bacteria.
11) Give an example of bacterial transposon.
12) Griffith’s experiment of transforming principle was conducted using virulent and non-virulent strains of ______________
(E.coli/ Pneumococci/Lambda phage)
13) Bacterial transposable elements have ____________ at the ends.
(inverted repeats/ poly-A tails/poly C-G pairs)
14) Define Gene flow
15) When a wild type of a phenotype undergoes mutation to give a mutant type of a phenotype the mutation is ________________.
16) Calculate proportion of polymorphic loci for a population of 25 frogs wherein 10 were polymorphic.
17) Give the full form of AGE.
18) Give an example of a restriction enzyme.
19) State true or false: Random mating is mating between genotypes occurring in proportion to the frequencies of the genotypes in the population.
20) ______________ is a type of genetic drift in which population, is initially established by a small number of breeding individuals. (bottleneck effect, founder effect)
Q. 2) A) In a pea plant, Purple flowers (P) are dominant over white flowers (p) and round seeds (R) are dominant over wrinkled seeds (r). Perform the following cross using Punnett square method to obtain the phenotype and genotype ratios of FI and generations.
A pea plant homozygous dominant for both the color of the flower and shape of the seed was crossed with a pea plant homozygous recessive for both the color of the flower and shape of the seeds. (8M)
Q. 2) B) Elaborate on Dominant epistasis. (7M)
OR
Q. 2) C) What are multiple alleles? Discuss briefly an instance of ABO blood group in man. (8M)
Q. 2) D) Explain the phenomenon of modification of law of dominance with a suitable example. (7M)
Q. 3) A) Discuss significance of F factor and sex pili in bacteria. (8M)
Q. 3) B) Explain the process of “specialized transduction with one example. (7M)
OR
Q. 3) C) Compare and contrast between transduction ‘and’ transformation. (8M)
Q. 3) D) illustrate the interrupted mating experiment for conjugation in bacteria. (7M)
Q. 4) Discuss with example the theory of Natural Selection. (8M)
Q. 4) B) Discuss speciation with suitable examples. (7M)
OR
Q. 4) C) Give hill for of PAGE? How PAGE is used by geneticists in measuring genetic variations at the protein level in a population? (8M)
Q. 4) D) Elaborate on Hardy Weinberg’s law and its assumptions. (7M)
Q. 5) Write Short notes on any three of the following. (15M)
a) Monohybrid cross.
b) Recessive epistasis.
c) Generalized transduction.
d Lysogeny in bacteriophages.
e) Computation of Allelic frequencies.
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