Which of the following statements is not true about hormones?

Step 1: Analyze the question We need the statement that is NOT true about hormones, so three options are true facts and one is false.

Step 2: Key concept Hormones are chemical messengers made by endocrine (ductless) glands. They are released into the blood and carried to target organs, where they cause specific effects. Their actions are generally slow and long-lasting, and they work automatically without conscious control.

Step 3: Check each option

• A. Their responses are voluntary: This is false. Hormonal responses are involuntary. You cannot consciously decide to switch them on or off. For example, you cannot choose to release insulin or adrenaline. Voluntary responses are controlled by the nervous system, such as deliberately raising your hand.
• B. They may affect more than one target organ: This is true. Adrenaline, for example, affects the heart, liver, blood vessels and more. Growth hormone and thyroxine also act on many tissues.
• C. They are chemical messengers in animals: This is true. It is the basic definition of a hormone.
• D. They are transported by the blood to the target organs: This is true. Hormones travel in the bloodstream.

Step 4: Answer The statement that is not true is A.

Exam tip: Remember the contrast. Nervous system = fast, short-lived, can be voluntary or reflex. Hormones (endocrine system) = slower, longer-lasting, involuntary, carried by blood. If an option says hormones are "voluntary," it is almost certainly the false one.