How did leaves modify to become stamen and pistils?

Sepals and petals are not directly involved in reproduction, while the stamens and pistils are the male and female reproductive organs. In addition, each flower possesses an ovary (at the base of the pistil) formed from modified leaves called carpels (note that the pistil itself is sometimes referred to as the carpel).

Explanation:

stimulus is a change in the environment that causes an organism to react. the response is the reaction to the stimulus. some examples of stimuli for zebras are drought, to many predators, and bad feeding grounds such as dead grass or plants. zebras respond to stimuli just like all other living organisms