Explain the physiological roles of thyroxine and adrenaline within the human body.
Describe the release of adrenaline from the adrenal glands in response to fear or stress, and its effect on heart rate, oxygen delivery, and the 'fight or flight' response.
Understand the function of thyroxine, secreted by the thyroid gland, in stimulating the basal metabolic rate and supporting growth and development.
Explain how thyroxine levels are strictly controlled through negative feedback mechanisms.
