Protein Metabolism Quiz

Protein Metabolism

• Two main processes involved in protein metabolism are anabolism (building of proteins) and catabolism (breakdown of proteins)

Protein Synthesis

• Three steps of protein synthesis are transcription, translation, and post-translational modification
• Transcription: copying DNA information into mRNA
• Translation: converting mRNA into a polypeptide chain
• Post-translational modification: adding carbohydrates, lipids, or phosphate groups to the polypeptide chain

Codons

• Codons are a sequence of three nucleotides that code for a specific amino acid or stop signal
• Codons code for 20 different amino acids and three stop signals

Protein Digestion

• Dietary proteins are broken down into peptides and amino acids in the gastrointestinal tract by enzymes like pepsin and trypsin
• Further broken down into individual amino acids that can be absorbed into the bloodstream

Non-Essential Amino Acids

• Non-essential amino acids are synthesized in humans through transamination or de novo synthesis
• Transamination: transferring an amino group from one amino acid to another
• De novo synthesis: synthesizing new amino acids from intermediates of glycolysis and the citric acid cycle