One of the carbohydrates is a building block of a plant's cell wall. It is

cellulose is a building block of a plant cell wall

Explanation:

answer; the tunica intima also called tunica interna, consists of elastic fibers,connective tissue and smooth muscle cells;

sorry to break it to ya but no one can answer your question it's just

jk but i am serious about the part that most people cant answer it beacuse you did not mention the section you are talking about. but it would if you added some detail and were a bit more specific.