Insect Growth Regulators (IGRs) are defined as:

Insect Growth Regulators (IGRs) are defined as:

• A. Plant essential oils that repel pests
• B. Natural hormones produced by insects
• C. Bacteria that inhibit growth
• D. Synthetic chemicals that disrupt insect development and life cycle

Answer: (D)

IGRs interfere with how insects grow and mature. They don’t usually kill on contact; instead they disrupt development and the life cycle by interfering with hormonal signals or the formation of the insect exoskeleton. This can keep larvae from molting to the next stage or prevent adults from reaching reproductive maturity, which over time reduces the pest population. That’s why they’re defined as synthetic chemicals designed to disrupt insect development and life cycle. They’re not just plant oils that repel pests, nor natural hormones produced by insects, nor bacteria that inhibit growth. The defining idea is a synthetic compound aimed at blocking the developmental processes that let pests grow and reproduce, rather than simply causing immediate death.

IGRs interfere with how insects grow and mature. They don’t usually kill on contact; instead they disrupt development and the life cycle by interfering with hormonal signals or the formation of the insect exoskeleton. This can keep larvae from molting to the next stage or prevent adults from reaching reproductive maturity, which over time reduces the pest population. That’s why they’re defined as synthetic chemicals designed to disrupt insect development and life cycle.

They’re not just plant oils that repel pests, nor natural hormones produced by insects, nor bacteria that inhibit growth. The defining idea is a synthetic compound aimed at blocking the developmental processes that let pests grow and reproduce, rather than simply causing immediate death.