Question

Define hormone? Mention the characteristics of hormones.

Answer 1

Hint: Hormones are chemical substances present in our body. They are formed in one part of the body and travel to other parts of the body to perform certain functions that they are formed for. From growth of the body to the reproductive system and other major functions are all regulated by hormones in our body.

Complete answer:
Hormones act like messenger molecules in the body. They are made in one part of the body and then they travel to other body parts of the body where they help control how cells and organs do their work.

The endocrine glands secretes hormones directly into the bloodstream. Hormones serve as messengers and help in controlling and coordinating various activities throughout the body.

Hormones are carried by the blood throughout the body but it affects only certain cells, only specific cells that respond to a given hormone have receptor sites for that hormone.

 If a hormone fits the receptor site, then there will be an effect. If a hormone and a receptor site do not match then there will be no reaction.

In total more than 200 hormones or hormone like molecules are discovered. Examples of few hormones- Luteinising hormone (LH), Follicle stimulating hormone (FSH), Prolactin, Growth hormone (GH), Oxytocin etc.

Hence, the correct answer is option (B).

Additional information:
Some main glands and hormones secreted by them:
- Hypothalamus releases antidiuretic hormone, oxytocin.
- Pituitary gland releases LH, FSH, GH, TSH, ACTH, oxytocin etc.
- Pineal gland has melatonin, Parathyroid gland has parathyroid hormone, Adrenal gland releases adrenaline, noradrenaline, cortisol, and aldosterone. Pancreas release insulin, ovaries in female release oestrogen, testes in male release testosterone.

Note: Hormones act only on target organs, they are the chemical substances that control and regulate the activity of cells and organs. Hormones are poured directly into blood and are carried throughout the body.