Hormones are normally absent in-

Correct option is D

The correct answer is (d) Bacteria.
· Hormones are chemical messengers produced by multicellular organisms, including humans and animals, to regulate physiological activities.
· Hormones are present in mammals like rats, monkeys, and cats, playing crucial roles in growth, metabolism, reproduction, and other bodily functions.
· Bacteria, being single-celled organisms, do not have complex systems that require hormones. Instead, they rely on other chemical signals like quorum sensing to communicate and regulate group behaviors such as biofilm formation.
· Hormones in animals are secreted by glands and affect target organs or tissues, coordinating complex body functions.
Additional Knowledge:
· Rats - Rats have a well-developed endocrine system that produces hormones such as insulin, growth hormone, and adrenaline, just like in humans.
· Monkeys - Monkeys, being primates, have an advanced hormone system similar to humans, regulating reproduction, metabolism, and stress responses.
· Cats - Cats, like other mammals, produce hormones such as thyroid hormones and cortisol that regulate various bodily processes including metabolism, growth, and response to stress.