What effect do juvenile hormones have on insects?

Juvenile hormones play a crucial role in the development and growth of insects, primarily by regulating their metamorphosis process. The primary function of these hormones is to maintain larval characteristics and prevent the insect from transitioning too quickly to adulthood. When juvenile hormone levels are high, they inhibit the maturation process, ensuring that the insect continues to develop through its larval stages rather than undergoing metamorphosis into the adult form.

In essence, rather than promoting the transition to adulthood, juvenile hormones ensure that the insect remains in its immature state until the appropriate conditions for maturation are met. This regulation is vital for proper growth and development, allowing insects to accumulate the necessary resources and readiness before reaching reproductive maturity and taking on their adult forms.

This is why the option regarding juvenile hormones interrupting metamorphosis accurately reflects their role in maintaining an insect's larval stage and delaying its progression to adulthood.