Evolution

A population of diploid organisms is at Hardy-Weinberg equilibrium. If the frequency of allele A is 0.1, the frequency of AA is .

1. 0.99
2. 0.01
3. 0.02
4. 0.10

Natural selection can lead to .

1. A and C only
2. A only
3. A, C and D only
4. A, B, C and D

Which one of the following factors will not affect the Hardy-Weinberg equilibrium?

1. Genetic recombination
2. Genetic drift
3. Gene migration
4. Constant gene pool

Match List-I with List-II : Choose the correct answer from the options given below :

1. A-III, B-II, C-I, D-IV
2. A-IV, B-II, C-III, D-I
3. A-I, B-II, C-III, D-IV
4. A-II, B-III, C-IV, D-I

Natural selection where more individuals acquire specific character value other than the mean character value, leads to

1. Stabilising change
2. Directional change
3. Disruptive change
4. Random change

The factor that leads to Founder effect in a population is :

1. Genetic drift
2. Natural selection
3. Genetic recombination
4. Mutation

A gene locus has two alleles A, a. If the frequency of dominant allele A is 0.4, then what will be the frequency of homozygous dominant, heterozygous and homozygous recessive individuals in the population?

1. 0.16 (AA); 0.48 (Aa); 0.36 (aa)
2. 0.16 (AA); 0.36 (Aa); 0.48 (aa)
3. 0.36 (AA); 0.48 (Aa); 0.16 (aa)
4. 0.16 (AA); 0.24 (Aa); 0.36 (aa)

In a species, the weight of newborn ranges from 2 to 5 kg. 97\% of the newborn with an average weight between 3 to 3.3 kg survive whereas 99\% of the infants born with weights from 2 to 2.5 kg or 4.5 to 5 kg die. Which type of selection process is taking place?

1. Disruptive Selection
2. Cyclical Selection
3. Directional Selection
4. Stabilizing Selection

Artificial selection to obtain cows yielding higher milk output represents :

1. directional as it pushes the mean of the character in one direction
2. stabilizing followed by disruptive as it stabilizes the population to produce higher yielding cows.
3. disruptive as it splits the population into two, one yielding higher output and the other lower output.
4. stabilizing selection as it stabilizes this character in the population.

Genetic drift operates in

1. slow reproductive population
2. large isolated population
3. non-reproductive population
4. small isolated population

In Hardy-Weinberg equation, the frequency of heterozygous individual is represented by

1. pq
2. p2
3. 2pq
4. q2

The tendency of population to remain in genetic equilibrium may be disturbed by :

1. lack of random mating
2. random mating
3. lack of migration
4. lack of mutations

Variation in gene frequencies within populations can occur by chance rather than by natural selection. This is referred to as :

1. Genetic drift
2. Genetic load
3. Genetic flow
4. Random mating

Random unidirectional change in allele frequencies that occurs by chance in all populations and especially in small populations is known as :-

1. Genetic drift
2. Migration
3. Mutation
4. Natural selection

Genetic variation in a population arises due to :

1. Reproductive isolation and selection
2. Mutations only
3. Mutations as well as recombination
4. Recombination only

If the mean and the median pertaining to a certain character of a population are of the same value, the following is most likely to occur:-

1. A normal distribution
2. A T-shaped curve
3. A skewed curve
4. A bi-modal distribution

Using imprints from a plate with complete medium and carrying bacterial colonies, you can select streptomycin resistant mutants and prove that such mutations do not originate as adaptation. These imprints need to be used -

1. On plates with minimal medium
2. Only on plates with streptomycin
3. Only on plates without streptomycin
4. On plates with and without streptomycin

At a particular locus, frequency of 'A' allele is 0.6 and that of 'a' is 0.4. What would be the frequency of heterozygotes in a random mating population at equilibrium?

1. 0.48
2. 0.24
3. 0.36
4. 0.16

Which of the following is not true for a species ?

1. Variations occur among members of a species
2. Gene flow does not occur between the populations of a species
3. Each species is reproductively isolated from every other species
4. Members of a species can interbreed

Random genetic drift in a population probably results from

1. Constant low mutation rate
2. Interbreeding within this population
3. Large population size
4. Highly genetically variable individuals

In a random mating population in equilibrium, which of the following brings about a change in gene frequency in a non-directional manner :-

1. Selection
2. Random drift
3. Mutations
4. Migration

Which of the following is important for speciation ?

1. Behavioural isolation
2. Seasonal isolation
3. Tropical isolation
4. Reproductive isolation

Genetic drift operates in : -

1. Slow reproductive population
2. Small isolated population
3. Large isolated population
4. Fast reproductive population

In which condition, the gene ratio remains constant for any species population ?

1. Gene flow
2. Mutation
3. Sexual selection
4. Random mating

Reason of diversity in living beings : -

1. Mutation
2. Short term evolutionary change
3. Long term evolutionary change
4. Gradual change

Forthcoming generations are less adaptive than their parental generation due to

1. Genetic drift
2. Natural selection
3. Mutation
4. Adaptation

In Lederberg's replica plating experiment, what shall be used to obtain a streptomycin-resistant strain?

1. Only minimal medium
2. Complete medium and streptomycin
3. Only complete medium
4. Minimal medium and streptomycin