Question

Internal stimulus comes from

• A. Inside an organism
• B. Outside an organism
• C. Skin
• D. None of the above

Answer 1

Answer: (A)

Inside an organism

• In physiology, a stimulus is a detectable change in the internal or external environment. The ability of an organism or organ to respond to external stimuli is called sensitivity.
• When a stimulus is applied to a sensory receptor, it normally elicits or influences a reflex. Hence, Internal stimulus comes from

Inside an organism.

So, the correct answer is 'Inside an organism'.