Thyroxine is the main hormone secreted into the bloodstream by the thyroid gland. It plays vital roles in digestion, heart and muscle function, brain development and maintenance of bones.
A singular subject is a noun or a pronoun for just one person, place, or thing. A plural subject is a noun or a pronoun that is two or more persons, places, or things. Exampl â¦ es: Singular subject: The boy came for lunch. He was hungry. Plural subject: The boys came for lunch.
Definition of subject. 1  1 : one that is placed under authority or control: such asa : vassalb (1) : one subject to a monarch and governed by the monarch's law (2) : one who lives in the territory of, enjoys the protection of, and owes allegiance to a sovereign power or state.