Exam 4 Misc Flashcards
Two backup systems in the liver to deal with Ammonia.
Periportal and Perivenous both located in the acinus
Periportal system
glutaminase releases NH3 from glutamine to make urea via the cycle
glutamate dehydrogenase releases NH3 from glutamate to create a-ketoglutarate
Perivenous system
glutamine synthetase scavenges excess NH3 to make glutamate and a-ketoglutate which are taken to the kidneys for deamination
Transamination
Amino Acid 1 + Keto Acid 2 –> Amino Acid 2 + Keto Acid 1
Deamination
Amino acid –> keto acid + NH3 (via dehydratase)
General Catabolic Site for amino acids
Most in liver and kidney with the branched chains in the muscle
Cause of Maple Syrup Urine Disease
Deficiency in the Branched Chain a-keto acid Dehydrogenase Complex
Cause of Phenylketonuria
Deficiency in the enzyme Phenylalanine Hydroxylase. Without it, Phenylalanine can’t be broken down to Tyrosine. It builds up and becomes phenylpyruvate / phenylketone
Catecholamines are derived from which amino acid?
Tyrosine
Which amino acid makes niacin and where?
Tryptophan in the liver
Which amino acid makes taurine?
Cysteine
Which amino acid makes Cysteine?
Methionine
Which amino acid is considered semi-essential and why?
Cysteine because infants and those with certain metabolic diseases or malabsorbtion syndrome are unable to get it
Which Amino Acids do not undergo transamination?
Lysine and Threonine
What happens physically when you do not consume enough essential amino acids?
Muscle degradation (body breaks down muscle to get protein), decreased immune response, weakness, fatigue, and changes to the texture of your skin and hair