hormon

• Nervous system


  A key communication network in the body, running like telephone wires and rapidly sending messages from the brain to a body part and back
• Endocrine system


  A slower "courier service" that takes messages on foot, composed of glands that produce hormones to affect changes in distant target organs
• Gland


  A group of cells that produce and secrete chemical messengers
• Types of glands


  • Exocrine glands (release secretions directly through a duct)
  • Endocrine glands (release secretions into the bloodstream)
• Major endocrine glands


  • Pituitary gland
  • Pineal gland
  • Thyroid
  • Thymus
  • Pancreas
  • Adrenal glands
  • Gonads (testes or ovaries)
• Hormones


  Chemical messengers released by endocrine glands that control various bodily functions
• How the endocrine system functions

  1. Change in the body occurs

  2. Endocrine system responds by releasing one or more hormones into the bloodstream

  3. Hormones travel through the body and affect change in a target organ
• Negative feedback


  When the feedback from the body stops the gland from producing more hormones
• Positive feedback


  When the hormone levels need to be raised higher and higher or lower and lower to continue a certain physiological response
• Hyper-


  Denotes too much of a hormone, e.g. hyperthyroidism
• Hypo-


  Denotes too little of a hormone, e.g. type 1 diabetes
• The endocrine system is largely dedicated to keeping your body in homeostasis, and this delicate balance is what keeps you alive
• Feedback mechanisms

  Processes that regulate hormone production and release, such as negative feedback, which helps maintain homeostasis in the body.
• Target organs

  Organs or tissues that receive and respond to hormones, such as the liver, pancreas, and reproductive organs.
• Hormones


  Chemical messengers produced and released by glands in the endocrine system that travel through the bloodstream to target organs or tissues, where they elicit a specific response.
• Endocrine system

  A system of glands and organs that produce and release hormones to regulate various functions in the body, such as metabolism, growth, and development.
• Glands

  Organs or tissues in the endocrine system that produce and release hormones, such as the pituitary gland, thyroid gland, and adrenal gland.