Muscle Breakdown, Nitrogen Balance & Amino Acid Catabolism

Question 1

Nitrogen Balance

Answer 1

When Nitrogen from Ingested Protein is equivalent to the Nitrogen Excreted

Question 2

How are Amino Acids converted to Urea

Answer 2

N Groups removed from aa to form Ammonium Ion (NH4+)

NH4+ converted to urea via urea cycle

Question 3

How are amino acids transported across membranes

Answer 3

Most amino acids are converted into alanine and glutamine since they are particularly stable and easy to transport

Much safer than transferring e.g. ammonia/ammonium

Question 4

Formation of urea in liver

Answer 4

Alanine and glutamine are converted into glutamate (Transamination), which is then converted into NH4+ that then becomes urea

Question 5

Transamination

Answer 5

Conversion of amino acid into a different molecule with glutamate using alpha ketoglutamate

Question 6

What process does glutamate undergo to form ammonium

Answer 6

Oxidative Deamination

**Reversible reaction

Question 7

Glucogenic vs Ketogenic Amino Acids

Answer 7