1. Protein Synthesis: This is the process by which cells create proteins, the workhorses of the cell. It involves two main steps:

* Transcription: DNA, the cell's genetic blueprint, is copied into RNA, a messenger molecule.

* Translation: RNA is used to build a protein from individual amino acids.

2. Cellular Respiration: This is the process by which cells break down glucose (sugar) to release energy in the form of ATP. This energy is used to power all cellular activities. Cellular respiration occurs in multiple steps, including glycolysis, the Krebs cycle, and the electron transport chain.

3. Cell Division: This is the process by which cells reproduce themselves. There are two main types of cell division:

* Mitosis: A single cell divides to create two identical daughter cells. This is used for growth and repair.

* Meiosis: A special type of cell division that creates gametes (sex cells) with half the number of chromosomes. This is essential for sexual reproduction.