← Amino Acids Test
5 Written Questions
5 Matching Questions
- How is Glutamate made? (2)
- What are the Amino Acids metabolic roles; What are the precursors of other N-containing substances (5)
- What does an amino acid ( α-amino and carboxly groups) look like?
(Don't have to know for test, but good for general knowledge)
- 1- How do people obtain ESSENTIAL amino acids? (1)
2- Why are ESSENTIAL AA not synthesized in the body?
- What do NON-ESSENTIAL AA require a source of?
- a 1- Obtained only in the DIET
2- Cannot be synthesized in body because Carbon skeletons (-C-C-C-) are not made or not made in sufficient quantity
- b 2- Still require a source of AMINO GROUPS
1- NH₃ (NH₄⁺ in water) can be added to α-ketoglutarate (common C-skelton) to make glutamate.
2- This rxn goes in both directions.
- d 1- Purines and pyrimidines (Eg. DNA, RNA)
2- Porphyrins (Eg. Heme)
3- Creatine (Eg. Muscle)
4- Melanin (Eg. Skin Pigment)
5- Hormones, neurotransmitters
** AAs used in nature are "L" stereoisomers (NH₃⁺) on left side of chiral carbon atom
5 Multiple Choice Questions
- 1- Glutaminase releases NH₃ from Gln
2- Glutamate dehydrogenase releases NH₃ from Glu
- NH₃ is excreted into urine as NH₄⁺
3- Kidneys also excrete urea that is produced by the LIVER.
Transamination uses an enzyme to move the α-amino group from GLY to another carbon skeleton
- 1- Liver converts excess NH₃ into urea which is eliminated by the kidneys
2- The body uses 2 main AA's, Glutamate (Glu) and Glutamine (Gln) to:
a- make use of available NH₃
b- get rid of excess NH₃
- Essential and Nonessential
5 True/False Questions
AA Picture summary →
1- Disease of AA Metabolism
What happens in Urea Cycle Enzyme Defects? (1)
2- What type of patients will you typically see this in? → 1) Accumulation of NH₃ and intermediates which will lead to neurological and developmental effects
There are 5 enzymes involved in the synthesis of urea. Name them and where this occurs → Essential and Nonessential
1- What are the clinically important transaminases (aminotransferases)? (2)
2- Why are these important? (2) → 1- Asparatate aminotransferase (AST)
2- Alanine aminotransferase (ALT)
* both listed above are found in liver cells
2- Serum levels of these enzymes can be measured and used as markers of cellular damage (This will tell us if the liver is damaged)
How is glutamine synthesized? →
Can be synthesized from glutamate