Somatotropin is growth hormone and gigantism is medical condition in which there is abnormal growth. Posterior part of pituitary is called as neurohypophysis. Neurohypophysis is structural foundation of neurohumoral system coordinating fluid balance and reproductive function. Parturition and lactation is done by oxytocin. Cretinism is seen in newborns. Cretinism is a condition due to deficiency of thyroid hormones. There are 2 types of thyroid hormones $\left(\mathrm{a}\right)$ Triiodothyronine and $\left(\mathrm{b}\right)$ Thyroxine. Vitamin D is a fat soluble vitamin. Rickets is a condition found in children's in which there is softening of bones due to deficiency of vitamin D.