Why ornithine is unlikely to be found in proteins in vivo mcat?

Ornithine is unlikely to be found in proteins in vivo mcat because not every amino acid found in the human body is identified by a codon in the genetic code or merged into proteins, that is Ornithine.

Ornithine is found as one of the intermediates in the urea cycle, the process of metabolism when the body excretes excess nitrogen. 

the correct answer is option d.

an appositive is a noun, noun phrase or noun clause which follows another noun or noun phrase in order to describe it or name it another way. they are usually used between commas, brackets or dashes.

the example sentence with the correct use of commas is the following:

her uncle, the man over there in the red shirt, owns the hardware store in town.

answer/// the nucleoid region contains dna; ///