1. The Nucleus: This is the control center of the cell, containing the cell's DNA, which carries the genetic instructions for the cell's function and reproduction.

2. The Cytoplasm: This is the gel-like substance that fills the cell and contains all the other cell organelles, like mitochondria, ribosomes, and the endoplasmic reticulum. The cytoplasm is the site of many important cellular processes, such as protein synthesis and energy production.