Amino Acid and Nitrogen Metabolism

What the page covers

The resources follow the path of nitrogen through the body. Some start with the nitrogen cycle and protein digestion. Others cover amino acid catabolism, nitrogen balance, ammonia, and the urea cycle. A large share of the mind maps look at urea cycle disorders and the role of citrulline in health and disease.

Where to start

Begin with the mind map Protein Metabolism and Urea Cycle. It sets out nitrogen balance as intake minus excretion, and explains positive and negative balance. Then open Amino Acid Catabolism, which sorts amino acids into glucogenic and ketogenic groups. Next, try Essential Amino Acids to see how glutamate transfers nitrogen by transamination.

Going deeper

• Ammonia metabolism shows why ammonia sits at the centre of nitrogen handling.
• The flashcard deck Glucose-Alanine Cycle and the deck Glutamine Transport cover how nitrogen moves between tissues.
• The deck Phenylalanine Metabolism and the mind map Errors of aa Metabolism cover inherited problems, including phenylketonuria.
• The mind maps Sulfur Metabolism and Amino Acid Derivatives take you to other fates of amino acids.

Using quizzes and maps together

Read a mind map first, then take a quiz without looking. The quiz Amino Acid Metabolism is a good first check. The longer quiz on the page asks which amino acids are essential, glucogenic or ketogenic. Note what you missed, go back to the matching map, and use flashcards to fix the details.

Where it sits

This unit belongs to the Metabolism strand of Biochemistry. It links naturally to the energy pathways you may already have studied, because amino acid carbon skeletons end up as glucose or acetyl-CoA.

Choose one map that matches your current lecture, try a quiz on it, and see which gaps remain. Teachers can pick any of these ready-made resources to share with a class.