Adrenaline and Thyroxine

• What is adrenaline and where is it released from?


  Adrenaline is a hormone released by the adrenal glands.
• In what situations is adrenaline released?


  Adrenaline is released in response to stressful or scary situations.
• How does the brain trigger the release of adrenaline?


  The brain detects fear or stress and sends messages to the adrenal glands.
• What physiological changes does adrenaline trigger in the body?


  Adrenaline increases the supply of oxygen and glucose to cells in the brain and muscles.
• What is the role of negative feedback in hormone release?


  Negative feedback helps control hormone levels in the blood.
• What happens when the level of a substance in the blood goes above or below normal range?


  The body triggers a response to bring the level back to normal again.
• What is thyroxine and where is it released from?

  Thyroxine is a hormone released by the thyroid gland.
• What is the role of thyroxine in the body?

  Thyroxine regulates the basal metabolic rate and stimulates protein synthesis for growth and development.
• What hormone stimulates the release of thyroxine?


  Thyroxine is released in response to thyroid stimulating hormone (TSH).
• How does the negative feedback system work for thyroxine?


  When thyroxine levels are high, TSH secretion is inhibited, reducing thyroxine release.
• What is the effect of high thyroxine levels on TSH secretion?


  High thyroxine levels inhibit the secretion of TSH from the pituitary gland.
• What happens to thyroxine levels when TSH secretion is reduced?


  The amount of thyroxine released from the thyroid gland decreases, lowering blood levels back to normal.