This depends on the animal. Different animals respond differently to the various stimuli they are exposed to. An animal that is naturally a prey-animal will run away when an animal that represents a...
These are called receptors. They can be of many different types, depending on what they perceive. Photoreceptors: Pick up light - like your eyes Chemoreceptors: Detect chemicals - like your nose and...
Warm-blooded creatures, like mammals and birds, try to keep the inside of their bodies at a constant temperature. They do this by generating their own heat when they are in a cooler environment, and...