To change behavior or actions in response to outside conditions 4 Letters. What is the word?

The four-letter word which speaks to the ability of an organism to modify its behavior or actions to external stimuli is Move.

Explanation:

Movement gives organisms the ability to move away from or towards an external stimulus depending on whether it is a detrimental stimulus or a favourable one.

Examples of stimuli are:

Light: All organisms respond to the presence of light. Some stay away from it and remain at sleep until the sun goes down. They are called nocturnal. Others gravitate towards it. Plants always grow towards light.Temperature: Some organisms favour cold environments, other the temperate parts of the earthSound: The sound of a carnivorous animal such as the lion will put a deer to flight. The sound of a mother hen calling out to her chicks will attract them to her.

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