1. In plants, the enzyme glutamine synthetase primarily catalyzes the:

  • A. Reduction of nitrate to nitrite
  • B. Conversion of glutamine to glutamate
  • C. Assimilation of ammonia into glutamine
  • D. Oxidation of ammonium to nitrate

Answer: C. Assimilation of ammonia into glutamine

Explanation: Glutamine synthetase incorporates ammonium into glutamate to form glutamine, the first step of the GS-GOGAT pathway.

2. Which of the following soil properties is least affected by the organic matter content?

  • A. Aggregate stability
  • B. Water-holding capacity
  • C. Bulk density
  • D. Particle density

Answer: D. Particle density

Explanation: Particle density depends mainly on the mineral composition of soil solids and changes very little with organic matter.

3. Cytoplasmic male sterility (CMS) is inherited primarily through the:

  • A. Nuclear genome
  • B. Y chromosome
  • C. Maternal cytoplasm
  • D. Pollen parent

Answer: C. Maternal cytoplasm

Explanation: CMS is controlled by mitochondrial genes that are inherited maternally through the cytoplasm.

4. Which insecticide belongs to the neonicotinoid group?

  • A. Malathion
  • B. Chlorpyrifos
  • C. Imidacloprid
  • D. Cypermethrin

Answer: C. Imidacloprid

Explanation: Imidacloprid is a neonicotinoid insecticide that acts on nicotinic acetylcholine receptors in insects.

5. The process by which DNA is copied into messenger RNA is known as:

  • A. Translation
  • B. Replication
  • C. Transcription
  • D. Translocation

Answer: C. Transcription

Explanation: During transcription, RNA polymerase synthesizes mRNA using DNA as the template.

6. Which disease of groundnut is caused by Aspergillus flavus and is associated with aflatoxin contamination?

  • A. Tikka disease
  • B. Collar rot
  • C. Aspergillus seed rot
  • D. Rust

Answer: C. Aspergillus seed rot

Explanation: Aspergillus flavus infects groundnut seeds and produces aflatoxins, which are highly toxic and carcinogenic.

7. Which of the following hormones is known as the "stress hormone" in plants?

  • A. Gibberellin
  • B. Cytokinin
  • C. Abscisic acid
  • D. Auxin

Answer: C. Abscisic acid

Explanation: Abscisic acid accumulates during drought and other stresses, inducing stomatal closure and seed dormancy.

8. Which experimental design is most appropriate when treatments are few and experimental units are highly homogeneous?

  • A. Completely Randomized Design (CRD)
  • B. Randomized Block Design (RBD)
  • C. Latin Square Design (LSD)
  • D. Split Plot Design

Answer: A. Completely Randomized Design (CRD)

Explanation: CRD is most suitable when experimental units are uniform and environmental variation is minimal.

9. Which of the following is the most common storage protein found in cereal grains?

  • A. Albumin
  • B. Globulin
  • C. Prolamin
  • D. Histone

Answer: C. Prolamin

Explanation: Prolamins such as gliadin (wheat) and zein (maize) are the principal storage proteins of cereals.

10. The inheritance pattern in which both alleles are fully expressed in the heterozygous condition is known as:

  • A. Incomplete dominance
  • B. Codominance
  • C. Epistasis
  • D. Pleiotropy

Answer: B. Codominance

Explanation: In codominance, both alleles are expressed simultaneously in the heterozygote, as seen in the AB blood group.