Parathyroid disorders: It causes the lowering of blood calcium level. This increases the excitability of nerves and muscles causing cramps and convulsions.

Correct Option: D

Parathyroid disorders: It causes the lowering of blood calcium level. This increases the excitability of nerves and muscles causing cramps and convulsions.

Graafian follicle – the ovarian medulla contains many rounded or oval bodies, called ovarian, or graafian follicles, at various stages of development. Each follicle contains a large ovum surrounded by many layers of follicle cells.

Correct Option: D

Graafian follicle – the ovarian medulla contains many rounded or oval bodies, called ovarian, or graafian follicles, at various stages of development. Each follicle contains a large ovum surrounded by many layers of follicle cells.

Parathyroid and adrenal are the endocrine glands. Adrenal glands are the pairs of endocrine glands situated immediately above the kidneys. Hence they are also known as suprarenal glands. Parathyroid glands are the two pairs of endocrine glands situated behind or embedded within the thyroid gland in higher vertebrates. They produce parathyroid hormone, which controls the amount of calcium in the blood.

Correct Option: A

Parathyroid and adrenal are the endocrine glands. Adrenal glands are the pairs of endocrine glands situated immediately above the kidneys. Hence they are also known as suprarenal glands. Parathyroid glands are the two pairs of endocrine glands situated behind or embedded within the thyroid gland in higher vertebrates. They produce parathyroid hormone, which controls the amount of calcium in the blood.

A peptide hormone secreted by the parathyroid gland in response to low levels of calcium in the blood. It acts to maintain normal blood levels of calcium by increasing the number of osteoclasts, which break down the bone matrix and release calcium into the blood. It also increases the reabsorption of calcium and magnesium ions in the kidney tubules, so that their concentration is maintained in the blood.

Correct Option: A

A peptide hormone secreted by the parathyroid gland in response to low levels of calcium in the blood. It acts to maintain normal blood levels of calcium by increasing the number of osteoclasts, which break down the bone matrix and release calcium into the blood. It also increases the reabsorption of calcium and magnesium ions in the kidney tubules, so that their concentration is maintained in the blood.

Myxoedema is caused by deficiency of thyroid hormone or thyroxine in adults. It is characterised by increase in body weight, puffy appearance, low metabolic rate, and tendency to retain water in tissues.

Correct Option: B

Myxoedema is caused by deficiency of thyroid hormone or thyroxine in adults. It is characterised by increase in body weight, puffy appearance, low metabolic rate, and tendency to retain water in tissues.