MCAER PG CET 2026 AGRIL ENTOMOLOGY

 

MCAER PG CET 2026

Agril. Entomology - Advanced Level

Time Remaining: 100s

1. The 'Reverse Dose-Response' phenomenon where low doses of a toxin result in stimulation is known as:

• Synergism
• Hormoligosis
• Potentiation
• Antagonism

Ans: b. Hormoligosis (Hormesis) occurs when sub-lethal doses of insecticides stimulate the reproductive capacity of pests (e.g., resurgence).

2. Which of the following is an example of an "Allomone" in insect-plant interaction?

• Floral scent attracting pollinators
• Trail pheromone in ants
• Secondary metabolites inhibiting herbivore feeding
• Aggregation pheromone

Ans: c. Allomones are semiochemicals that benefit the emitter (the plant) but are harmful to the receiver (the insect).

3. [PYQ 2021] The juvenile hormone (JH) is secreted by which endocrine gland?

• Corpora cardiaca
• Prothoracic gland
• Corpora allata
• Neurosecretory cells

Ans: c. Corpora allata secretes JH which maintains the larval characteristics during molting.

4. In insect toxicology, the "I-value" refers to:

• Insecticide Index
• Inhibitory value of an enzyme
• Inter-dose interval
• Ignition temperature

Ans: b. The I-value (e.g., I50) indicates the concentration of an inhibitor required to reduce enzyme activity by 50% (Crucial in Organophosphate studies).

5. [PYQ 2023] Which respiratory organ is characteristically found in aquatic Hemipterans like Nepa (Water Scorpion)?

• Tracheal gills
• Siphon / Respiratory tube
• Plastrons
• Blood gills

Ans: b. Nepa uses a terminal respiratory siphon to breathe atmospheric air while submerged.

6. The mode of action of Diamide insecticides (e.g., Chlorantraniliprole) involves:

• AChE inhibition
• Sodium channel modulation
• Ryanodine receptor activation
• Chitin synthesis inhibition

Ans: c. Diamides target Ryanodine receptors, leading to unregulated calcium release from muscle cells, causing paralysis.

7. "Thelelytoky" is a form of parthenogenesis where:

• Only males are produced
• Only females are produced
• Both sexes are produced
• No offspring are produced

Ans: b. Thelytoky is common in Aphids where unfertilized eggs develop into females.

8. Which mouthpart component is modified into 'Galeae' for sucking nectar in Lepidopterans?

• Mandibles
• Labium
• Maxillae
• Hypopharynx

Ans: c. The proboscis of butterflies and moths is formed by the interlocking of two highly elongated Galeae of the Maxillae.

9. What is the 'Economic Injury Level' (EIL) mathematically defined as?

• C / VDK
• V / CDK
• CDK / V
• K / VCD

Ans: a. EIL = C / (V * D * K), where C=Cost of control, V=Market value, D=Damage per unit pest, K=Reduction in damage.

10. The phenomenon where a parasite is itself parasitized by another parasite is:

• Superparasitism
• Multiparasitism
• Hyperparasitism
• Adelphoparasitism

Ans: c. Hyperparasitism involves a secondary parasite attacking a primary parasite.

Review the explanations above for correct answers.