Endocrine system

• What is the other way to send information around the body apart from neurones?

  Using hormones
• What are hormones?

  • Chemical messengers in the blood
  • Produced in endocrine glands
  • Affect specific target cells
• How are hormones released into the body?

  They are released directly into the blood
• What are target cells?

  Cells that have receptors for specific hormones
• Where are adrenal glands located?

  Just above the kidneys
• What does adrenaline prepare the body for?

  'Fight or flight' response
• How does adrenaline affect the heart?

  Increases heart rate and blood pressure
• What does adrenaline do to glucose levels in the blood?

  Increases blood glucose level
• What triggers the release of adrenaline?

  Nervous impulses from the brain
• How does negative feedback work in hormone regulation?

  • Detects levels above or below normal
  • Triggers a response to restore normal levels
  • Example: Thyroxine regulation
• What is thyroxine?

  A hormone released by the thyroid gland
• What role does thyroxine play in the body?

  Regulates metabolic rate
• What hormone stimulates the release of thyroxine?

  Thyroid stimulating hormone (TSH)
• What happens when thyroxine levels are too high?

  TSH secretion is inhibited
• What does FSH stand for?

  Follicle Stimulating Hormone
• What does FSH do?

  Stimulates ova and sperm production
• What is the role of oestrogen?

  Involved in the menstrual cycle
• What does progesterone do?

  Supports pregnancy and menstrual cycle
• What are the stages of the menstrual cycle?

  1. Menstruation (Day 1-5)
  2. Follicular phase (Day 6-14)
  3. Ovulation (Day 14)
  4. Luteal phase (Day 15-28)
• What happens during menstruation?

  The uterine lining sheds
• What occurs during ovulation?

  An egg is released from the ovary
• What does FSH do during the menstrual cycle?

  Matures an egg in the ovary
• What does oestrogen do to the uterine lining?

  Thickens and grows the lining
• What triggers the release of LH?

  Stimulated by oestrogen
• What does LH do during the menstrual cycle?

  Stimulates egg release at ovulation
• How are hormones used in fertility treatments?

  • Hormones can stimulate ovulation
  • FSH and LH can be injected
  • Used in IVF to promote egg production
• What is IVF?

  In vitro fertilization
• What happens during IVF?

  Eggs are fertilized in a lab
• What hormones are given before egg collection in IVF?

  FSH and LH
• What is the role of hormones in contraception?

  • Help prevent ovulation
  • Regulate menstrual cycle
  • Used in hormonal contraceptives
• What does it mean if a person is infertile?

  They can't reproduce naturally
• How can infertility be treated?

  Through modern reproductive technologies
• What hormones are used to promote natural pregnancy?

  FSH and LH
• What happens if a woman has low levels of FSH?

  No ovulation takes place
• How can FSH and LH be administered to stimulate ovulation?

  By injection
• What does IVF stand for?

  In vitro fertilisation
• What is the process of IVF?

  Collecting eggs, fertilising in a lab
• What happens to embryos in the IVF process?

  They are transferred to the woman's uterus
• Why are FSH and LH given before egg collection in IVF?

  To stimulate egg production
• What is the purpose of contraceptives?

  To prevent pregnancy