Sample question paper

A researcher observes that in a particular flowering plant, the pistil matures several days before the stamens in all flowers of the plant. What is the most significant consequence of this timing difference?

1. AIt guarantees self-pollination
2. BIt promotes autogamy
3. CIt ensures cross-pollination
4. DIt leads to geitonogamy

A male patient undergoes a medical procedure where a small section of the vas deferens is cut and tied at both ends. Which of the following effects is the intended and direct result of this procedure?

1. ABlockage of sperm transport into the ejaculatory duct and urethra.
2. BInhibition of testosterone production by the testes.
3. CSuppression of the formation of seminal plasma by accessory glands.
4. DPrevention of spermatogenesis in the seminiferous tubules.

During the early stage of human embryonic development, the blastomeres are arranged into an outer layer and an inner group of cells known as the Inner Cell Mass (ICM). What is the fundamental significance of the outer layer, the trophoblast?

1. AIt is responsible for forming the primary germ layers (ectoderm, mesoderm, endoderm).
2. BIt provides essential nutrients to developing embryo and helps in its implantation.
3. CIt secretes colostrum which contains antibodies.
4. DIt gives rise to all the organs of the future embryo (organogenesis).

A scientist was culturing E.coli in a ¹⁵NH₄Cl medium initially, then he shifted E.coli to a ¹⁴NH₄Cl medium. The DNA was extracted from E.coli after 60 minutes of transfer to ¹⁴NH₄Cl Medium and performed density gradient centrifugation to check the isotope distribution in newly replicated DNA. What will be the densities of DNA molecules formed?

1. A25% hybrid and 75% light
2. B50% hybrid and 50% light
3. C75% hybrid and 25% light
4. D85% hybrid and 15% light

A patient with fever, chest pain, cough and breathing difficulty undergoes a chest X-ray. The film shows patchy opacities and reduced clarity of lung fields. Which observation best supports pneumonia?

1. AEnlarged heart size
2. BInflammation or fluid buildup in the lungs
3. CFractured ribs
4. DAir pockets in the lungs

A stretch of an euchromatin has 200 nucleosomes, how many base pairs (bp) will be there in the stretch and what would be the length of the typical euchromatin?

1. A20,000 bp and 13,000x10⁻⁹ m
2. B10,000 bp and 10,000x10⁻⁹ m
3. C40,000 bp and 13,600x10⁻⁹ m
4. D40,000 bp and 13,900x10⁻⁹ m

A biotechnology company grew Streptomyces in a fermenter to produce an antibiotic. It was observed that Day 7 onwards, the actual yield drops sharply, even though nutrient level, temperature, and aeration remain unchanged. Also, Microscopy revealed new colonies of bacteria which were not present in the original culture. So the fermenter was stopped. What measures should be taken to prevent the fall in yield in future fermentations?

1. AIncreasing temperature only at the end of fermentation to kill contaminants.
2. BAdding antibiotics to the culture so unwanted microbes cannot grow.
3. CEnsuring sterile handling, sterilised equipment, and aseptic transfer before and during fermentation.
4. DUsing a genetically modified strain designed to grow faster than contaminants.

A rice farmer's field, which typically thrives in waterlogged conditions and requires soil rich in nutrients like phosphorus, is experiencing a severe drought this year. The crop is also susceptible to root infestation by pathogens. Which of the following techniques is best to address all these issues?

1. AAdding nitrogen-fixing bacteria to the soil
2. BApplying chemical fertilizers
3. CAdding spores of Glomus to the soil
4. DFlooding the field artificially to mimic normal conditions