Chemical substances such as insulin, adrenaline, and estrogen that stimulate activities in the body are called

Chemical substances such as insulin, adrenaline, and estrogen that stimulate activities in the body are called

• A. Circulatory System
• B. Melanin
• C. Hormones
• D. Hair Follicle

Answer: (C)

Hormones are chemical messengers that stimulate activities in the body. They are produced by endocrine glands and travel through the bloodstream to target organs, where they trigger specific responses. For example, insulin helps regulate blood sugar, adrenaline prepares the body for quick action, and estrogen influences reproductive development. The other terms refer to a system (circulatory system), a pigment (melanin), or a structure (hair follicle) and do not describe signaling chemicals, so they aren’t the correct fit.

Hormones are chemical messengers that stimulate activities in the body. They are produced by endocrine glands and travel through the bloodstream to target organs, where they trigger specific responses. For example, insulin helps regulate blood sugar, adrenaline prepares the body for quick action, and estrogen influences reproductive development. The other terms refer to a system (circulatory system), a pigment (melanin), or a structure (hair follicle) and do not describe signaling chemicals, so they aren’t the correct fit.