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27 Cards in this Set
- Front
- Back
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Under anaerobic conditions what is the fate of pyruvate in humans? Yeast?
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Anaerobic!
In humans the fate of pyruvate is lactate In yeast the fate of pyruvate is ethanol |
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What compound is trapped by sodium sulfite in the Pyruvate lab?
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Acetaldehyde
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In the pyruvate lab, what enzyme involved in the fermentation process will be inhibited by ALKALINE solution in this lab? What intermediate will be trapped in the process?
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Pyruvate decorboxlyase
Pyruvate Basically the reaction can't proceed to change pyruvate into acetaldehyde and ethanol |
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What gas is given off through fermentation? What will be the molecular form of t his gas in BASIC conditions?
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CO2
Bicarbonate |
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What reacts with acetaldehyde to produce a blue color in the pyrvuate lab?
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Sodium nitroprusside and piperdine will specifically react with acetaldehyde to produce a blue color
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What organisms will be used in the pyruvate lab?
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Yeast
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What are the three compounds that represent pyruvate's possible fates? What determines each pathway?
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Acetyl-CoA - Mammal and microorganisms, AEROBIC conditions
Lactate - Bacteria ANAEROBIC Ethanol - Yeast ANAEROBIC |
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What enzyme is inhibited by mild alkaline solution in the pyruvate lab?
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Pyruvate decarboxlyase is inhibited by mild alkaline (BASIC) solutions in the pyruvate lab.
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Sodium sulfite in the pyruvate lab is used to trap and detect accumulation of what?
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Acetaldehyde
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In the pyruvate lab, what reacts with pyrvuate to produce a red color at ideal pH values?
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2-4-dinitrophenylhydrazine will specifically react with pyruvate to produce a red color at ideal pH.
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Does yeast function aerobically or anaerobically? What does it produce?
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Yeast functions anaerobically.
Anaerobic yeasts converts pyruvate to acetaldehyde and ethanol |
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What chemical in the pyruvate lab will be used to trap acetaldehyde?
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Sodium sulfite
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What chemical will be used to test for the alpha ketoacid in the pyruvate lab?
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Na2HPO4
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What alpha ketoacid are we testing for in the pyruvate lab?
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2,4-dinitrophenyldefrazones
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in the pyruvate lab, does sample 1 produce gas? Why?
Sample 1 contains yeast, base |
No, sample 1 is in an alkaline which deactivates pyruvate decarboxylase so pyruvate accumulates.
The reaction from pyruvate to acetaldehyde produces CO2. |
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In the pyruvate lab, does sample 2 produce gas, why?
Sample 2 contains yeast, acid |
Yes, sample 2 is in an acidic solution so it doesn't effect pyruvate decarboxlyase
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In the pyruvate lab, does sample 3 produce gas? Why?
Sample 3 contains yeast, H2O |
Yes, sample 3 has H2O and is not basic enough to deactivae pyruvate decarboxlyase
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In the pyruvate lab, does sample 4 produce gas? Why?
Sample 4 contains yeast, sodium sulfite |
Some gas is produced because sodium sulfite raises pH, but not high enough to completely deactivate pyruvate decarboxlyase. The pH is high enough to keep CO2 dissolved in solution as bicarbonate.
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In the pyruvate lab, does sample 5 produce gas? Why?
Sample 5 contains sugar and h2O |
No, no yeast for a reaction
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What was the yellow precipitate in the pyruvate lab?
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2,4-dinitrophenylhydrazone
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Within any cell, the concentration of what metabolites determine the fate of pyruvate?
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[NAD+] and [NADH]
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What enzymes within humans serves the same purpose under anaerobic conditions as alcohol dehydrogenase does within yeast?
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Lactate dehydrogenase
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Why does alcohol fermentation occur to a much greater extent under anaerobic conditions vs aerobic conditions? In other words, what purpose do the fermentation reactions serve for the yeast cell?
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To produce NAD+
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What occurs during the process of malting?
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Barely seeds germinate
Barely forms enzymes required to break down polysaccharides Germination stopped via heat |
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What occurs during the process of making "wort"?
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Malt + h2o is smashed together to promote enzymes breaking up pollysaccharides. This forms maltose, glucose, and simple sugars in solution.
This is then filtered, then boiled with hops for flavor |
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What is the fate of carbons derived from sugars when yeast is initially allowed to multiply under aerobic conditions?
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Pyruvate --> CO2 + H2O via citric acid cycle
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What is the source of foam or head within beers? How is it controlled?
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Dissolved proteins form head. Its controlled by protelytic enzymes that arise during malting process.
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