State briefly what happens to a protein molecule in food, from the time it is swallowed, to the time its products are built up in the cytoplasm of a muscle cell.

When a protein molecule in food is swallowed, it is broken down into its constituent amino acids by enzymes in the stomach and small intestine. These amino acids are then absorbed into the bloodstream and transported to muscle cells. In the cytoplasm of a muscle cell, the amino acids are used to build up new proteins through a process called protein synthesis. This process involves the ribosomes in the cell reading the genetic code in the cell's DNA and assembling the amino acids into specific sequences to form new proteins.

- Swallowing: The protein is broken down into smaller peptides by enzymes in the stomach.
- Small intestine: The peptides are further broken down into amino acids by enzymes in the small intestine.
- Absorption: The amino acids are absorbed into the bloodstream through the walls of the small intestine.
- Liver: The amino acids are processed by the liver and transported to the muscles.
- Muscle cells: The amino acids are used to build new proteins in the cytoplasm of the muscle cells.