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 singular for Students. 1  1 : of, relating to, or being a word form used to show not more than one person or thing The singular form of âcalvesâ is âcalf.â. 2  2 : 1superior 2, exceptional He showed singular poise. 3  3 : of unusual quality We had a singular experience.