Control of Metabolism

Question 1

BMR (Basal Metabolic Rate)

Answer 1

• a baseline/reference point of a persons rate of metabolism
• person must be awake, fasted for 12 hours, rested
• affected by insulin, sex hormones etc but not REGULATED

Question 2

What regulates BMR? What else does it control?

Answer 2

thyroid glands
- prolonged stress and cold exposure

Question 3

Thyroid Hormones

Answer 3

• iodine + tyrosine = thyroid hormone

Question 4

Use a FBL to explain how thyroid hormones work

Answer 4

cold –> hyp stimulated –> releases TRH –> pit gland stimulated –> releases TSH –> thyroid releases T3/T4 –> increase BMR. glucose levs = H+ leak in mitochondria = thermal energy produced

Question 5

Goiter

Answer 5

low iodine = low t4 = incr. TSH stimulates hormones to make more t4 = builds up in the thyroid

Question 6

Cretinism

Answer 6

no t3/t4 in baby = developmental delays

Question 7

Hypothyroidism

Answer 7

• TSH not being secreted or thyroid damaged
  1. primary: thyroid cant produce the hormone orders from pit gland
  2. secondary: thyroid isnt stimulated by pit gland to make hormones
• low bmr = tired
• treated with pills that have synthetic thyroid hormones

Question 8

Hyperthyroidism

Answer 8

• thyroid is being overactive = inc bmr = hot, weightloss

Question 9

Grave’s Disease

Answer 9

autoimmune bodies mimic TSH and overstimulate the thyroid