All are TRUE about thyroid gland, EXCEPT:: (A) Development stas at 3rd week of gestation, (B) It develops from the floor of the primitive pharynx, (C) Ectopic location of the thyroid gland is at the base of the tongue, (D) Thyroid hormone synthesis begins at 20th week of gestation
Answer is D. The thyroid develops from the floor of the primitive pharynx during the third week of gestation. Rare ectopic location of thyroid tissue is at the base of the tongue (lingual thyroid) The hormone synthesis normally begins at about 11 weeks' gestation. Ref: Harrison, E-18, P-2911