Which organelle contains genetic material and is essential for cell function?

• A. Nucleus
• B. Chromosomes
• C. Cytoplasm
• D. Plasma membrane

Answer: (A)

The main idea is where genetic information is stored and used to run the cell. The nucleus houses the cell’s DNA, organized into chromosomes, and it acts as the control center that regulates gene expression and DNA replication. This makes it essential for cell function because the instructions for making proteins and for cell division are stored here and managed by the nucleus. The other options don’t fit as the repository or regulator of genetic material: chromosomes are DNA-protein structures inside the nucleus, not separate organelles; cytoplasm is the fluid that surrounds organelles and does not contain organized genetic material; the plasma membrane is the outer boundary and does not contain DNA.