Following are the graphical representations of various hypotheses

Subject

Life Sciences

Class

CNET Class 12

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 Multiple Choice QuestionsMultiple Choice Questions

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131.

Following are the graphical representations of various hypotheses proposed for explaining the possible relationships between species richness (X-axis) and community services (Y-axis).

Which of the following options is the correct match between the graphical representations and the hypotheses?

  • (a) Redundancy; (b) Keystone; (c) River; (d) Idiosyncratic

  • (a) Idiosncratic; (b) River; (c) Keystone; (d) Redundancy

  • (a) Rivet; (b) Redundancy; (c) Idiosyncratic; (d) Keystone

  • (a) Rivet; (b) Keystone; (c) Redundancy; (d) Idiosyncratic


C.

(a) Rivet; (b) Redundancy; (c) Idiosyncratic; (d) Keystone

The correct match is-

(a) Rivet; (b) Redundancy; (c) Idiosyncratic; (d) Keystone


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132.

Following are the plots representing biological rhythms at different time points depicted as: SR - Sunrise; N = North; SS - Sunset; MN - Midnight

Which of the plot(s) represent the ultradian biological rhythm(s)?

  • Plot B

  • Plots A and C

  • Plots C and D

  • Plot D


133.

A population of non-poisonous butterflies have the same colour pattern as some highly poisonous butterflies. Assume that the population of non-poisonous butterflies is higher thanthe population of poisonous butterflies. Given this, what will be the impact of this mimicry on the fitness of the population of the poisonous butterflies in the presence of the predator?

  • It will lower the fitness, that is, the fitness of the mimic is negatively frequency-dependent.

  • It will increase the fitness, that is, fitness of the mimic is positively frequency-dependent.

  • It will not affect the fitness, that is, fitness of the mimic is frequency independent.

  • It will increase the fitness, that is, the fitness of the mimic is negatively frequency-dependent.


134.

Given below is a graphical representation of changes in morphological features over a period of geological time scale, where population A accumulates heritable morphological changes and give rise to a distinct species B. Population B splits into a distinct species B.

Which of the above lineages represent the pattern of speciation by cladogenesis?

  • Lineage 1

  • Both the lineages 1 and 2

  • Lineage 2

  • Neither of the lineages 1 and 2


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135.

Red hair is a recessive trait in humans. In a randomly mating population in Hardy -Weinberg equilibrium, approximately 9% of individuals are red-haired. What is the frequency of heterozygotes?

  • 81%

  • 49%

  • 42%

  • 18%


136.

The frequency of M-N blood types in a population of 6129 individuals is as follows:
Blood type Genotype Number of individuals
M LMLM 1787
MN LMLN 3039
N LNLN 1303

The frequency of Lallele in this population is

  • 0.4605

  • 0.2121

  • 0.5395

  • 0.2911


137.

Mafair genes (hypothetical) consist of a super family of transcription factor. They are found in 4 clusters in mammals; in 2 clusters in insects; and in a single cluster in an ancestor to insects. These data are consistent with all of the following explanations EXCEPT:

  • Two successive genome duplication events occurred between ancestral organism and vertebrates.

  • The first duplication may have taken place before the divergence of vertebrates.

  • Exon shuffling exclusively produced such cluster.

  • Whole-genome duplications could lead to such observations.


138.

Fluorescence recovery after photobleaching (FRAP) is a method to estimate the diffusion of molecules in a membrane. Fluorescently labeled molecules such as-

i. a receptor tagged with green fluorescent protein(GFP)

ii. a receptor labeled with GFP which interacts with cytoskeleton.

iii. a labeled lipid.

iv. a labeled protein that binds to the membrane surface

are photobleached and the recovery profiles (a-d) were obtained to estimate their diffusion coefficients.

The following data were obtained:

Which one of the combinations is correct?

  • a - i; b - ii

  • b - iii; a - iv

  • c - iii; d - iv

  • d - ii; b - i


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139.

Agrobacterium Ti plasmid vectors are used to generate transgenic plants. The following are examples of vir gene-encoded proteins that are important for the transfer of T-DNA into plants:

A. Vir E, a single-stranded DNA binding protein.

B. Vir D2 that generates T-strands.

C. Vir A that senses phenolic compounds.

D. Vir F which directs T-complex proteins for destruction in proteasomes.

Which one of the following combinations of proteins functions inside the plant cells?

  • Only A and C

  • A, B, and C

  • Only B and C

  • A, B, and D


140.

A researcher is investigating structural changes in a protein by following tryptophan fluorescence and by circular dichroism (CD). Fluorescence and CD spectra of a pure protein were obtained in the absence of any treatment (a), in the presence of 0.5M Urea (b), upon adding acrylamide, a quencher of tryptophan (c) and upon heating (d). The data are shown below:

Which one of the following statements is correct?

  • CD is more sensitive to structural changes than fluorescence.

  • Fluorescence is more sensitive to structural changes than CD.

  • Both methods are equally responsive to structural changes.

  • Acrylamide alters the secondary structure of the protein.


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