Most cells (excluding bacteria) have three main parts:
1. The cell membrane is a thin but tough covering made of lipids and proteins that forms the outside of the bag. [ The cell membrane protects the inner contents of the cell, gives the cell shape and supports and controls what goes in and out of the cell.
2. The cytoplasm (means cell substance) contains water, various salts, and many large macromolecules. The cytoplasm ... (More)