Define hormones and their special features.
Special features of hormones include
They are secreted by endocrine cells,
They are chemical signals,
They circulate in bodily fluids,
They regulate behaviour of other cells.
They do not catalyse any reactions.
They may or may not be proteinaceous.
They are secreted as per the need and not stored.
Hormone:A chemical substance produced in the body that controls and regulates the activity of certain cells or organs. Many hormones are secreted by special glands, such as thyroid hormone produced by thethyroid gland. Hormones are essential for every activity of life, including the processes of digestion, metabolism, growth, reproduction, and mood control. Many hormones, such as neurotransmitters, are active in more than one physical proces