Question

Endostyle metamorphoses into
(A) Parathyroid
(B) Thyroid
(C) Thymus
(D) Thalamus

Answer 1

Hint: It is a groove present on the wall of the pharynx of urochordates and cephalochordates. Endostyle produces iodinated tyrosine molecules. It also helps in transporting food to the esophagus.

Complete answer:
The endostyle seems to produce iodinated, tyrosine molecules that may function as thyroxine hormone produced by the thyroid gland. The thyroid hormone which is produced by the thyroid consists of Iodine as one of the elements of the hormone. Thyroid cells combine amino acid and iodine to form T3 and T4 thyroid hormone.
The thyroid gland is situated at the neck. It is located below Adam’s apple. The thyroid gland is a butterfly-shaped organ and it consists of two lobes. It is an endocrine gland. Endocrine glands are the glands that secrete their secretions or hormones directly into the blood. The thyroid is rich in blood vessels and is a reddish-brown color.
T3 and T4 are two different hormones secreted by the thyroid gland and have the name triiodothyronine and thyroxine respectively. The number 3 and 4 are decided by the number of iodine atoms present per molecule i.e T3 contains three atoms of iodine per molecule and T₄ contains four atoms of iodine per molecule.

So the correct answer is ‘(B) Thyroid’.

Note: Metamorphosis is a process in which an animal or a cell develops after birth or during its life span and converts into another specific cell or organ through cell growth and differentiation which looks different than the previous one. Animals or cells that perform metamorphosis are called metamorphoses.