AP BIOLOGY

Detailed explanation-1: -The nuclear membrane is a double layer that encloses the cell’s nucleus, where the chromosomes reside. The nuclear membrane serves to separate the chromosomes from the cell’s cytoplasm and other contents.

Detailed explanation-2: -The nuclear envelope (NE) is a highly regulated membrane barrier that separates the nucleus from the cytoplasm in eukaryotic cells. It contains a large number of different proteins that have been implicated in chromatin organization and gene regulation.

Detailed explanation-3: -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-4: -Answer: (c) Its inner membrane bears ribosomes. This statement is not true.

Detailed explanation-5: -In eukaryotic cells, the nucleus is separated from the cytoplasm and surrounded by a nuclear envelope. This envelope safeguards the DNA contained in the nucleus.