The Endocrine System

• What is the endocrine system?

  The endocrine system is a network of glands that secrete hormones into the bloodstream to regulate body functions.
• What are hormones?

  Hormones are chemical messengers that travel in the blood and control processes like growth, metabolism, and reproduction.
• How do hormones affect the body?

  • Hormones are released by glands into the bloodstream.
  • They travel to target organs where they trigger a response.
• What are the major glands in the endocrine system?

  • Pituitary gland – "Master gland" that controls other glands.
  • Thyroid – Regulates metabolism.
  • Pancreas – Controls blood sugar levels.
  • Adrenal glands – Produce adrenaline for the "fight or flight" response.
  • Ovaries (females) – Produce oestrogen for the menstrual cycle.
  • Testes (males) – Produce testosterone for sperm production.
• Why is the pituitary gland called the "master gland"?

  The pituitary gland produces hormones that control other endocrine glands, regulating body functions like growth and reproduction.
• What is the function of the thyroid gland?

  The thyroid gland produces thyroxine, which regulates metabolism, heart rate, and temperature.
• What hormones does the pancreas produce and what do they do?

  • Insulin – Lowers blood sugar by storing glucose in cells.
  • Glucagon – Raises blood sugar by releasing glucose from the liver.
• What do the adrenal glands produce and why?

  Adrenal glands produce adrenaline, which prepares the body for "fight or flight" by increasing heart rate and breathing rate.
• What hormones control the menstrual cycle?

  • Oestrogen – Stimulates the uterus lining to grow.
  • Progesterone – Maintains the uterus lining.
  • FSH (Follicle Stimulating Hormone) – Stimulates egg development.
  • LH (Luteinising Hormone) – Triggers ovulation.
• What hormone do the testes produce and what does it do?

  The testes produce testosterone, which controls sperm production and male puberty.