CBSE Class 10 Answered

Parathyroid gland - Parathyroid hormone. if calcium ion concentrations in extracellular fluid fall below normal, this hormone brings them back within the normal range. In conjunction with increasing calcium concentration, the concentration of phosphate ion in blood is reduced.

Thymus - Thymic hormone. They participate in the development of the lymphoid system and the maturation of the cellular immune response.

Pineal gland - Melatonin. This hormone communicates information about environmental lighting to various parts of the body. Ultimately, melatonin has the ability to entrain biological rhythms and has important effects on reproductive function of many animals. It also has some effect in maintaining the normal sleep cycles.