7.13A,B External and Internal Stimuli

- All organisms maintain a stable balance of internal conditions for survival. This is called homeostasis. A change in the external or the internal conditions of the organism is called a stimulus. An organism responds to the external or the internal stimuli to maintain a balanced stable conditions and survive.

- the Plants will possibly respond to an external stimulus. An animal could respond to an external stimulus.

- Plants may respond to an internal stimulus. an example of internal stimulus is if there is a lack of water. Animals reacted in many different ways,for example, vomiting when they have eaten spoiled food.