Which term refers to the living matter within a cell?

The term that refers to the living matter within a cell is protoplasm. Protoplasm encompasses everything within the cell membrane, including the cytoplasm, organelles, and the cell nucleus, all of which are essential components of cellular function and life.

Protoplasm is often considered the "substance of life" as it contains the necessary materials for cellular processes such as metabolism, growth, and reproduction. It plays a critical role in various biological functions, acting as the medium where essential biochemical reactions occur.

Other terms listed, such as plasma, prokaryote, and eukaryote, refer to different concepts. Plasma typically describes the fluid portion of blood in a biological context, while prokaryotes and eukaryotes are classifications of organisms based on cellular structure. Prokaryotes are single-celled organisms without a nucleus, whereas eukaryotes have cells that contain a nucleus and organelles. Understanding these distinctions helps clarify why protoplasm is the most accurate term representing living matter within a cell.