List of practice Questions

A mature rat sperm cell has 2.5 µg of genomic DNA that is equivalent of a haploid genome. Compared to this sperm cell, the amount of genomic DNA (in µg) in a somatic cell, which is in the G2 phase of cell cycle, will be _______ (in integer).

Which of the following antibiotics is/are isolated from Streptomyces spp.?

Which of the following statements about the primary and secondary adaptive immune responses to an antigen is/are correct?

The spontaneous, and induced mutations in bacteria can be distinguished by

Which one of the following animals has “Book Lungs” as a respiratory organ?

Which one of the following is NOT correct about antibiotic resistance mechanism in microbes?

Determine the correctness or otherwise of the following Assertion [a] and the Reason [r]. Assertion [a]: Endospore can survive heat that would rapidly kill vegetative cells of the same species.
Reason [r]: In endospore, the protoplasm is reduced to minimum volume as a result of the accumulation of calcium-dipicolinic acid complexes and small acid-soluble spore proteins, which forms a cytoplasmic gel and a thick cortex.

Which one of the following conjugations will result in formation of merodiploids?

Which of the following genus is/are a spirochete(s)?

Which of the following is/are non-membrane bound inclusion bodies?

Which one of the statements about bacterial flagella is correct?

Microbial plastics are made from:

The correct sequence of metabolic intermediates in the Krebs cycle is:

Catabolite repression in bacteria is regulated by the concentration of

Phagocytosis was first described by

Which one of the following statements about batch culture of microbes is NOT correct?

Blue light can directly induce opening of stomata. Blue light also triggers photosynthesis in the guard cells, which indirectly induces stomatal opening. Which one or more of the following experimental approaches would test the direct effect of blue light on stomatal opening?

In a diploid angiosperm species, flower colour is regulated by the R gene. RR and Rr genotypes produce red flowers, whereas the rr genotype produces white flowers. If two individual plants are randomly selected from a large segregating population of a genetic cross between RR and rr parents, the probability of both the plants producing red flowers is _______. (Rounded off to two decimal places)

A cytoplasmic male-sterile female plant with the restorer (nuclear) genotype rr is crossed to a male-fertile male plant with the genotype RR. Both RR and Rr can restore the fertility, whereas rr cannot. When an F1 female plant with Rr genotype was test-crossed to a male-fertile male plant with the rr genotype, the percentage of the population that is male fertile would be _______. (Answer in integer)

The frequencies for autosomal alleles A and a are $p = 0.5$ and $q = 0.5$, respectively, where A is dominant over a. Under the assumption of random mating, the mating frequency among dominant parents is ................ (Rounded off to two decimal places).

Monkeypox is caused by a

Which one of the following converts sulfate to hydrogen sulfide?

Central vascular cylinder or stele consists of the primary vascular system (xylem and phloem) and the associated fundamental tissue. Match the schematics of stele in Group I (xylem shown in green, and phloem shown as with their respective types in Group II. \includegraphics[width=0.75\linewidth]{image58.png}

Consider four observations about the FT gene and flowering transition in the shoot apical meristem (SAM) of Arabidopsis thaliana:
(i) The FT promoter is active in leaves alone.
(ii) The ft null mutation causes delayed flowering of the SAM.
(iii) Expressing a recombinant FT protein fused to a nuclear localization signal (NLS) under the endogenous promoter does not rescue the delayed-flowering phenotype of the ft null mutant.
(iv) Downregulation of FT transcript in the SAM by RNAi in a wild-type background does not alter flowering.
Which conclusion best explains these observations?

A drought tolerant rice genotype was found to be associated with a missense mutation in the gene A. Which one or more of the following experiments is/are appropriate to validate whether the mutation in A is the causal factor for drought tolerance?