LIFE SCIENCE

Detailed explanation-1: -The nucleus is surrounded by a system of two concentric membranes, called the inner and outer nuclear membranes. The outer nuclear membrane is continuous with the endoplasmic reticulum, so the space between the inner and outer nuclear membranes is directly connected with the lumen of the endoplasmic reticulum.

Detailed explanation-2: -The nucleus of the cell is a membrane-bound organelle that includes the nuclear envelope, nucleolus, and nuclear matrix, and is the site of gene expression. The nucleus can be selectively visualized by staining nuclear proteins or directly staining nucleic acids.

Detailed explanation-3: -All eukaryotic cells (those found in animals, plants, protists, and fungi) have a control center called the nucleus. This is where genetic material, or DNA, is stored. Surrounding every nucleus is a double-layered membrane called the nuclear membrane or nuclear envelope.