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All MCQs
Browse exam-wise, subject-wise, and country-wise MCQs with explanations.
Choose an option to check your answer.
A.
simple eyes mainly detecting light intensity
B.
chewing jaws for solid food
C.
hooks for mating only
D.
tubes for excretion
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Correct Answer: A. simple eyes mainly detecting light intensity
Explanation:
Ocelli are simple light-sensitive organs. They generally help insects detect light intensity and maintain orientation rather than forming detailed images.
Choose an option to check your answer.
A.
digestion of cellulose in the gut
B.
chemical hardening and darkening of cuticle after molting
C.
fusion of gametes during fertilization
D.
softening of muscles before flight
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Correct Answer: B. chemical hardening and darkening of cuticle after molting
Explanation:
Sclerotization strengthens the cuticle after ecdysis by cross-linking cuticular proteins. It gives insects firm body plates and protective hard parts.
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A.
jumping leg used for escape
B.
wax layer that prevents drying
C.
piercing tube used for blood feeding
D.
feathery antenna adapted for detecting airborne signals
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Correct Answer: D. feathery antenna adapted for detecting airborne signals
Explanation:
Plumose antennae have many hair-like branches, increasing surface area. This is useful for detecting faint chemical signals, such as sex pheromones in some insects.
Choose an option to check your answer.
A.
antennae digest proteins
B.
labellar surfaces absorb liquid food
C.
large mandibles cut hard wood
D.
spiracles filter pollen grains
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Correct Answer: B. labellar surfaces absorb liquid food
Explanation:
Houseflies use sponging mouthparts to take liquid or liquefied food. The labella help spread and absorb food from surfaces.
Choose an option to check your answer.
A.
chewing jaws for solid food
B.
hooks for mating only
C.
simple eyes mainly detecting light intensity
D.
tubes for excretion
Show Answer
Correct Answer: C. simple eyes mainly detecting light intensity
Explanation:
Ocelli are simple light-sensitive organs. They generally help insects detect light intensity and maintain orientation rather than forming detailed images.
Choose an option to check your answer.
A.
fusion of gametes during fertilization
B.
chemical hardening and darkening of cuticle after molting
C.
digestion of cellulose in the gut
D.
softening of muscles before flight
Show Answer
Correct Answer: B. chemical hardening and darkening of cuticle after molting
Explanation:
Sclerotization strengthens the cuticle after ecdysis by cross-linking cuticular proteins. It gives insects firm body plates and protective hard parts.
Choose an option to check your answer.
A.
jumping leg used for escape
B.
feathery antenna adapted for detecting airborne signals
C.
wax layer that prevents drying
D.
piercing tube used for blood feeding
Show Answer
Correct Answer: B. feathery antenna adapted for detecting airborne signals
Explanation:
Plumose antennae have many hair-like branches, increasing surface area. This is useful for detecting faint chemical signals, such as sex pheromones in some insects.
Choose an option to check your answer.
A.
antennae digest proteins
B.
large mandibles cut hard wood
C.
labellar surfaces absorb liquid food
D.
spiracles filter pollen grains
Show Answer
Correct Answer: C. labellar surfaces absorb liquid food
Explanation:
Houseflies use sponging mouthparts to take liquid or liquefied food. The labella help spread and absorb food from surfaces.
Choose an option to check your answer.
A.
shedding of the old cuticle to allow growth
B.
production of pheromones by antennae
C.
movement of hemolymph through spiracles
D.
development of adult wings inside eggs
Show Answer
Correct Answer: A. shedding of the old cuticle to allow growth
Explanation:
Because the exoskeleton cannot expand continuously, insects grow by molting. Ecdysis is the shedding stage in which the old cuticle is cast off.
Choose an option to check your answer.
A.
labium forms a coiled sucking tube
B.
spiracles grind plant tissue
C.
mandibles cut and crush solid food
D.
Malpighian tubules bite and chew
Show Answer
Correct Answer: C. mandibles cut and crush solid food
Explanation:
Chewing mouthparts rely on strong mandibles. Grasshoppers and cockroaches use this type to cut, crush, and process solid food.
Choose an option to check your answer.
A.
the region that bears walking legs only
B.
a blood-filled tube that forms the heart
C.
a soft abdominal sac for gas exchange
D.
a sclerotized structure bearing eyes, antennae, and mouthparts
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Correct Answer: D. a sclerotized structure bearing eyes, antennae, and mouthparts
Explanation:
The insect head is a hardened capsule made of fused segments. It supports feeding structures and major sensory organs such as compound eyes and antennae.
Choose an option to check your answer.
A.
shedding of the old cuticle to allow growth
B.
production of pheromones by antennae
C.
development of adult wings inside eggs
D.
movement of hemolymph through spiracles
Show Answer
Correct Answer: A. shedding of the old cuticle to allow growth
Explanation:
Because the exoskeleton cannot expand continuously, insects grow by molting. Ecdysis is the shedding stage in which the old cuticle is cast off.
