What are Hormones?

  • Hormones are chemical substances produced by glands in the endocrine system.
  • They are secreted directly into the bloodstream and carried to target cells or organs.
  • Hormones are the body’s natural messengers, controlling a variety of bodily functions.

Hormones and the Endocrine System

  • The endocrine system is a network of glands that produce and secrete hormones to regulate bodily functions.
  • Major endocrine glands include the pituitary gland, thyroid gland, adrenal glands, pancreas, ovaries, and testes.
  • Each gland produces specific hormones that play different roles in the body.

Roles of Hormones

  • Hormones regulate various functions such as metabolism, growth and development, tissue function, sleep, mood, and reproduction.
  • For example, insulin is a hormone produced by the pancreas that regulates glucose levels in the blood.
  • Thyroxine, produced by the thyroid gland, controls the rate of metabolism, heart rate, and temperature in the body.

Control of Hormone Production

  • The production and release of hormones are regulated by a feedback mechanism.
  • For instance, if the level of a certain hormone is too high in the blood, the endocrine system reduces its production and vice versa.
  • This ensures that the body maintains homeostasis.

Hormones vs Nervous System

  • Hormones and the nervous system both play crucial roles in regulating body functions, but their mechanisms of action are different.
  • While hormones use the circulatory system and often have slow, prolonged effects, the nervous system uses nerve impulses for quick, short-term responses.
  • The two systems often work in tandem to maintain balanced bodily functions.