Low $Ca^{++}$ in the body fluid may be the cause of

Which hormone increases $Ca^{++}$ levels?

The hormone responsible for the regulation of calcium and phosphorus metabolism is secreted by:

Exchange of calcium between bone and extracellular fluid takes place under the influence of certain hormones.
$(a)$ What will happen if there is an excess of $Ca^{++}$ in the extracellular fluid?
$(b)$ What will happen if there is a very low amount of $Ca^{++}$ in the extracellular fluid?

Demineralization of bone resulting in softening,bending,and fracture of bones,common in women who have reached menopause,is called i and is caused due to ii .

The hormone that maintains the levels of calcium and phosphorus in the blood is secreted by which of the following?