EXAM 3 Flashcards
(77 cards)
** How many ATP are utilized in the Gamma-glutamyl cycle to resynthesize glutathione?
- ) 2 ATP
- ) 4 ATP
- ) 1 ATP
- ) 3 ATP
4 (3 ATP)
** What cofactor assists aminotransferases like ALT and AST in their ability to transfer amino groups?
- ) Pyridoxal-5-Phosphate
- ) Vitamin B5
- ) Pyridoxamine Phosphate
- ) Vitamin C
1.
** Alanine aminotransferase converts alpha-ketoglutarate into glutamate and alanine into:
- ) Pyruvate
- ) Aspartate
- ) Oxaloacetate
- ) Glutamate
1.
** Elevations in BUN indicate increased load of ammonia. Checking the OA profile, you find high orotate levels, which could indicate there is a genetic SNP in the enzyme _____________.
- ) ornithine transcarbamoylase (OTC)
- ) argininesuccinate synthetase (ASS)
- ) argininosuccinate lyase (ASL)
- ) arginase
1
** AST, ALT, CPK, and _____ are all enzymes that can be indicators of liver damage, which in turn means impaired liver function.
- ) gamma-glutamyl transpeptidase
- ) gamma-glutamyl cyclotransferase
- ) pyroglutaminase
- ) GSH synthase
1.
** Sickle Cell Anemia is caused by a point mutation leading to a structural instability of the RBC. What conditions can create increased stress, leading to increased levels of deoxyhemoglobin and sickle cell crisis?
A: All of these responses 1.) Decreased pH (acidity) 2.) High altitude 3.) Increased 2,3-Bisphosphoglycerate A
A.
** True or False: Phosphofructokinase 1, Glucokinase, and Pyruvate Kinase are all upregulated in response to insulin.
T
** Antacids can reduce the absorption of iron and copper, leading to iron deficiency anemia because:
- ) Because the antacids bind the metals
- ) Acidic pH increases Fe3+
- ) DMT1 requires co-transport of H+ ions to internalize divalent cations
- ) Stomach acid properly degrades metals
3.
**Copper-containing ferroxidases called Hephaestin and __________ convert Fe2+ to Fe3+ so it can be safely transported by transferrin in the bloodstream
Ceruloplasmin
** Which transporter assists in uptake of iron from the intestines?
- ) Divalent metal transporter 1 (DMT1)
- ) Ferritin
- ) Ferrireductase duodenal cytochrome b
- ) Transferrin
1.
** The Bohr effect explains that a decrease in the amount of oxygen associated with hemoglobin (Hb) due to a reduced affinity of oxygen for Hb is the result of:
- ) Increased pC02 and increased pH
- ) Increased pCO2 and decreased pH
- ) Decreased pC02 and decreased pH
- ) Decreased pC02 and increased pH
2
** The Cori cycle:
- ) All of these responses
- ) Converts 2 lactate into glucose
- ) Is upregulated in a fasting state
- ) Produces 2 ATP in peripheral tissues
1
** Obesity and chronic overnutrition interrupt metabolic pathways in the following way(s):
- ) High NADH reduces creation of Acetyl CoA and TCA cycle
- ) All of these responses
- ) High ATP reduces glycolysis and TCA cycle
- ) High pyruvate and acetyl CoA increase FA
- ) Excess glucose converts to glycogen
2
**True or False: Phosphofructokinase 1, Glucokinase, and Pyruvate Kinase are all upregulated in response to insulin.
T
** High levels of ATP in the cell indicate increased energy reserves. Hence, high levels of ATP will:
- ) Appear during a fasting state
- ) Enhance activity of glycogen phosphorylase
- ) Enhance activity of isocitrate dehydrogenase
- ) Block activity of pyruvate kinase
4
High ATP will shut down phosphofructokinase and pyruvate kinase of glycolysis to slow production of more ATP
** The Alanine Cycle:
- ) Does not require ATP
- ) Occurs in a well-fed state
- ) Releases alanine from the liver
- ) None of these responses
4
Alanine cycle converts 2 alanine from peripheral tissue into glucose in the liver during a FASTING state
Requires ATP and produces 5-7ATP in peripheral tissues
of ATPs produced in peripheral tissues via Cori v. Alanine cycle
Cori = 2
Alanine = 5-7
** Advanced glycation end-products (AGEs) are created when glucose reacts spontaneously with ___(a)___ on proteins to create ____(b)___ products that spontaneously and irreversibly degrade to form AGEs.
- ) (a) amino acids, (b) Maillard reaction
- ) (a) amino acids, (b) Fenton reaction
- ) (a) organic acids, (b) Maillard reaction
- ) (a) organic acids, (b) Fenton reaction
1.
** The first step in the formation of heme (porphyrinogen pathway) involves the substrates glycine and succinyl CoA being converted to _(a)__ by the enzyme (b).
- ) (a) delta-aminolevulinic acid, (b) delta-aminolevulinic acid synthase
- ) (a) ALA, (b) ALA dehydratase
- ) (a) succinate, (b) succinate dehydrogenase
- ) (a) hydroxymethylbilane, (b) hydroxymethylbilane snythase
1
** Porphyrias can occur from prolonged fasting because low glucose intake leads to:
- ) upregulation of ALAS1
- ) downregulation of ALAS1
- ) upregulation of ALA dehydratase
- ) downregulation of ALA dehydratase
1
** ALA + ALA -> porphobilinogen via the enzyme (a) which requires (b).
- ) (a) delta-ALA dehydratase, (b) Zinc
- ) (a) ALA synthase, (b) Zinc
- ) (a) porphobilinogen deaminase, (b) NH3
- ) (a) hydroxymethylbilane synthase, (b) NH3
1
** GI conjugase enzymes hydrolyze folate to the monoglutamate form. What cofactor is needed for this reaction?
- ) Vitamin C
- ) Zinc
- ) Copper
- ) Magnesium
2
** The folate trap occurs when there is deficient amounts of vitamin B12 and folate gets “trapped” in the form _______________.
- ) 5,10 Methylene-THF
- ) 5-Methyl-THF
- ) THF
- ) 10-Formyl-THF
2
** Elevations of FIGLU in the urine can indicate:
- ) Functional deficiency of vitamin B12
- ) Functional deficiency of histidine
- ) Functional deficiency of glutamate
- ) Functional deficiency of folic acid
4