Negative Feedback

• What is the function of the adrenal glands and thyroid gland?

  • Adrenal glands produce adrenaline during stress
  • Thyroid gland releases thyroxine for metabolism and growth
• Why are oxygen and glucose important during the fight or flight response?

  They are essential for aerobic respiration to generate energy.
• What are the two main effects of thyroxine?

  • Stimulates the body's basal metabolic rate
  • Plays an important role in growth and development
• How is the level of thyroxine in the blood controlled?

  It is controlled by negative feedback mechanisms.
• What hormone does the pituitary gland release to regulate thyroxine levels?

  TSH (Thyroid Stimulating Hormone).
• Describe the negative feedback cycle for thyroxine regulation.

  1. Thyroxine level falls
  2. Pituitary gland releases TSH
  3. Thyroid gland releases more thyroxine
  4. Increased thyroxine detected by the brain
  5. Pituitary gland stops releasing TSH
  6. Thyroxine level decreases
• What happens when thyroxine levels become too high?

  Events are triggered to bring thyroxine levels back down.