Which substance within the nucleus contains genetic material?

The substance within the nucleus that contains genetic material is nucleoplasm. Nucleoplasm is the gel-like substance that fills the interior of the nucleus and houses the cell's genetic material, which is primarily composed of DNA. This genetic material is organized into structures called chromosomes, and it plays a crucial role in cell division and the regulation of cellular activities.

Ribosomes are involved in protein synthesis and are found in the cytoplasm or attached to the endoplasmic reticulum, not within the nucleus. The cytoplasm refers to the entire contents of a cell, excluding the nucleus, and does not directly contain genetic material. The cell membrane serves as a protective barrier that encloses the entire cell, including the nucleus, but it does not contain genetic material itself. Thus, the nucleoplasm is specifically responsible for housing and organizing the genetic material within the nucleus.