Before the discovery of these glands, thyroid surgery often led to a rapid drop in blood calcium levels, which triggered muscle contractions and cardiac arrhythmias. what glands are these and which hormone is lacking? thyroid glands; levothyroxine parathyroid glands; calcitonin parathyroid glands; levothyroxine parathyroid glands; parathyroid hormone thyroid glands; calcitonin

Answer;

C) parathyroid glands; parathyroid hormone

Explanation;

-Parathyroid glands (humans, four) are imbedded in the thyroid gland and they secrete the parathyroid hormone (PTH). So-called C cells dispersed throughout the thyroid gland, the parathyroids and thymus secrete another hormone, calcitonin. Both hormones play a significant role in the maintenance of calcium homeostasis.

-PTH, a polypeptide secreted in response to hypocalcemia raises the concentration of plasma calcium by;  increasing renal calcium reabsorption, mobilizing calcium from bones by stimulating osteoclastic activity, in the presence of adequate amounts of vitamin D, stimulating the absorption of calcium from the small intestine; and lowering levels of plasma inorganic phosphate by inhibiting renal reabsorption of phosphate

your spelling is a little off : ]

i think the answer is a.keratin is the pigment responsible for skin color.