Parathyroid hormone a. increases bone formation and lowers blood calcium levels, b. increases calcium excretion from the body, c. decreases calcium absorption from the gut, d. demineralizes bone and raises blood calcium levels.

Video transcript

Hi, everyone. Our next problem says the following are the functions of the parathyroid hormone except choice. A stimulates bone resorption. B enhances calcium reabsorption. C enhances phosphate reabsorption or D increases the activation of vitamin D. So we're looking for the one answer. Choice that is not a function of the parathyroid hormone or we'll call it PTH, make it a little shorter. So choice a stimulates bone resorption and that is the process of breaking down bone tissue to release calcium into the bloodstream. And this is a function of the parathyroid hormone or PTH. So it's not our correct answer to B which is enhances calcium reabsorption. This also is a function of PTH. Uh it increases that absorption of calcium by the kidneys so that less calcium is excreted in urine and it helps maintain proper calcium levels in the body. So not our answer. Since it is another function of the PTH, then we get choice c enhances phosphate reabsorption. Well, this is not a function of the PTHPTH actually decreases phosphate reabsorption by kidneys. So it means more phosphate is excreted in urine and this helps to maintain the calcium phosphate balance in the body. So since this is not a function of pth, choice C will be our answer. Finally, just to be thorough choice D increases the activation of vitamin D. This is true, it increases the activation of vitamin D in the kidneys. And this causes increased absorption of calcium from the intestines. So since it is a function of pth, it's not our answer. And we, we can kind of see that um all of the functions of PTH involve increasing calcium levels in the body, both breaking down bone tissue to release calcium to the bloodstream, enhancing calcium reabsorption and retention in the body and then increasing that activation of vitamin D, which helps the body get more calcium from digestion. But again, the one that is not a function of PTH is choice c enhances phosphate reabsorption as it does exactly the opposite. See you in the next video.