Pakistan MCQs

Photoreceptors detect light and begin visual processing. They occur in compound eyes and ocelli, helping insects respond to movement, day length, and orientation cues.

Johnston's organ is located in the pedicel of the antenna. It detects antennal movements and is important in hearing or flight-related sensory feedback in some insects.

Ecdysone is a major molting hormone. It activates events leading to apolysis, new cuticle formation, and eventual shedding of the old cuticle.

Incomplete metamorphosis lacks a pupal stage. Nymphs gradually develop adult structures through successive molts.

Photoreceptors detect light and begin visual processing. They occur in compound eyes and ocelli, helping insects respond to movement, day length, and orientation cues.

Johnston's organ is located in the pedicel of the antenna. It detects antennal movements and is important in hearing or flight-related sensory feedback in some insects.

Ecdysone is a major molting hormone. It activates events leading to apolysis, new cuticle formation, and eventual shedding of the old cuticle.

Incomplete metamorphosis lacks a pupal stage. Nymphs gradually develop adult structures through successive molts.

Mechanoreceptors detect physical forces such as touch, vibration, stretch, or air movement. Sensory hairs and chordotonal organs are common insect examples.

Pheromones are chemical messages released by one individual and detected by another. They can guide mating, alarm behavior, trail following, or aggregation.

Juvenile hormone influences developmental outcome. High levels tend to maintain juvenile characteristics, while low levels permit adult differentiation during metamorphosis.

Holometabolous insects often reduce intraspecific competition because larvae and adults differ in form, food, and habitat. This helps explain their evolutionary success.