Nutrition & Dietary Needs Flashcards

Which nutrient class provides the primary energy source for most insects during flight?

Answer: Lipids

Lipids (particularly stored fat) serve as the primary fuel for sustained insect flight due to their high energy density.

What is the term for insects that feed exclusively on plant sap from the phloem?

Answer: Phloem feeders

Phloem feeders, such as aphids and whiteflies, use piercing-sucking mouthparts to access nutrient-rich phloem sap.

Symbiotic microorganisms in the gut of wood-boring beetles primarily help the host by:

Answer: Synthesizing essential amino acids

Endosymbiotic bacteria in wood-borers supplement the nitrogen-poor wood diet by synthesizing essential amino acids the host cannot produce.

Which of the following is an example of a stenophagous insect?

Answer: Monarch butterfly larva

Monarch butterfly larvae are stenophagous, feeding almost exclusively on milkweed (Asclepias spp.).

The primary role of sterols in insect nutrition is to:

Answer: Serve as precursors for molting hormones

Insects cannot synthesize sterols de novo and must obtain them from the diet; sterols are essential precursors for ecdysteroids (molting hormones).

Which feeding guild describes insects that consume decaying organic matter and contribute to nutrient cycling?

Answer: Detritivores

Detritivores, such as dung beetles and certain fly larvae, feed on decomposing organic matter and play a critical role in nutrient cycling.

Blood-feeding insects such as mosquitoes primarily use blood proteins for:

Answer: Egg development (vitellogenesis)

Female mosquitoes require a blood meal rich in proteins to fuel vitellogenesis — the production of yolk proteins necessary for egg maturation.