Question

which two hormones closely control levels of calcium in the blood? t3 and t4 acth and aldosterone calcitonin and parathyroid hormone epinephrine and norepinephrine

Explanation:

T3 and T4 regulate metabolism; ACTH/aldosterone manage stress and fluid balance; epinephrine/norepinephrine handle fight-or-flight responses. Only calcitonin (lowers blood calcium) and parathyroid hormone (raises blood calcium) work together to tightly control blood calcium levels.

Answer:

Calcitonin and parathyroid hormone