Which organelle houses DNA and is considered the brain of the cell?

• A. Nucleus
• B. Mitochondria
• C. Golgi apparatus
• D. Ribosome

Answer: (A)

The key idea is where the genetic material is kept and how the cell is guided. The nucleus is the organelle that houses the cell’s DNA and acts as the command center, controlling which genes are turned on or off and directing overall cellular activities. It’s enclosed by a double membrane called the nuclear envelope, with channels (pores) that regulate what enters and leaves. Inside, DNA is organized with proteins as chromatin, and the nucleolus within the nucleus is where ribosomal RNA is made to build ribosomes.

Mitochondria do carry some DNA, but their main role is energy production, not directing the cell. The Golgi apparatus processes and ships proteins, and ribosomes synthesize proteins, but neither stores the genetic blueprint. So the organelle that houses DNA and steers the cell’s activities is the nucleus.