The hormone that stimulates the contraction of the uterus during childbirth is: MCQ with Answer and Explanation

Explanation:
The pituitary gland is a pea-sized endocrine gland located at the base of the brain, in a bony cavity called sella turcica, attached to the hypothalamus by a stalk (infundibulum). It is divided into anterior and posterior pituitary, secreting hormones that regulate growth, reproduction, metabolism, and other endocrine glands. Thus, it's in the head, not neck or abdomen.

Explanation:
Azolla is an aquatic fern that harbors the nitrogen-fixing cyanobacterium Anabaena azollae in its leaf cavities. It is extensively used as a biofertilizer in rice paddies, adding organic nitrogen. Rhizobium fixes nitrogen in legume roots, Azotobacter is free-living in soil, mycorrhiza is a fungal association enhancing phosphorus uptake. Azolla multiplies rapidly and improves soil fertility.

Explanation:
Diabetes insipidus results from insufficient ADH or kidney response, causing polyuria and polydipsia with dilute urine. Diabetes mellitus is hyperglycemia.