Hormonal Regulation of Blood Calcium Levels
Regulation of High Blood Calcium Levels
1) calcium levels rise from calcium rich foods 2) calcitonin producing cells in thyroid sense this 3) secrete CT into blood 4) CT targets the bone-degrading cells in skeletal system (ostoeclasts) 5) plasma membrane in osteoclasts contain receptors for CT and they bind, which inhibits cells from doing their normal job of degrading bone 6) CT does not affect osteoblasts & they carry on depositing calcium salts in bone causing the blood calcium to fall 7) CT stops being produced when blood calcium levels return to normal
Regulation of Low Blood Calcium Levels
1) have not eaten calcium rich foods 2) blood calcium levels fall 3) detected by 2 pairs of parathyroid glands and secrete PTH into the blood 4) PTH targets osteoclasts (bone-degrading cells) ****osteoclasts contain receptors for PTH 5) PTH docks at its PTH receptor stimulating osteoclasts to decompose bone and release calcium into the blood 6) blood calcium levels rise, PTH stops being produced when blood calcium levels return to normal
what is the normal blood calcium level?
9-11 mg/dL
is parathyroid hormone and calcitonin necessary for life?
PTH is necessary for life CT is not only in pregnant women
what happens if you do not have PTH?
calcium levels would fall so low that it would impair normal muscle contraction and blood clotting
what are calcium rich foods?
milk, broccoli, tofu causing blood calcium levels to rise
what are the bone forming cells in the skeletal system?
osteoblasts deposite calcium salts in bone
what are the bone degrading cells in the skeletal system?
osteoclasts