PATHOLOGY

Detailed explanation-1: -Smell, sound, etc., are examples of external stimuli and hunger, thirst, etc., are examples of internal stimuli.

Detailed explanation-2: -Internal stimuli are changes, experiences, or feelings that occur within someone. Examples include hunger, thirst, and emotional states. Internal stimuli are often contrasted with external stimuli, which are changes or experiences that occur outside.

Detailed explanation-3: -Hunger is an internal stimulus. Animals need food for several reasons. If animals did not have the hunger stimulus, they may not eat and could not survive.

Detailed explanation-4: -Stimulus: any change in an organism’s environment that causes the organism to react. It is a fancy way of saying “cause”. Example: An animal is cold so it moves into the sun.