1. Plasma membrane: This is the outer boundary of the cell, acting as a barrier between the cell's internal environment and its surroundings. It controls what enters and exits the cell.

2. Cytoplasm: This is the gel-like substance that fills the cell and contains all the cell's organelles. It provides a medium for biochemical reactions and supports the cell's shape.

3. Genetic material (DNA): This contains the instructions for the cell's activities and is responsible for passing on hereditary information. It can be found in the nucleus in eukaryotic cells or the nucleoid region in prokaryotic cells.

Let me know if you'd like a more detailed explanation of any of these components!