Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
77 Cards in this Set
- Front
- Back
What is oxidative phosphorylation?
|
Making ATP energy from the protonmotive force.
|
|
The protonmotive force works as...
|
an electrochemical gradient.
|
|
Describe the conditions in the periplasmic space.
|
Acidic and Positively Charged
|
|
Why is the electrochemical gradient a source of potential energy?
|
H+ cannot diffuse through the membrane.
|
|
Who won the Nobel Praice for oxidative phosphorylation chemiosmosis work?
|
Peter Mitchell
|
|
What does allow the protons into the cell?
|
ATP synthase and transmembrane proteins.
|
|
What two things does ATP synthase do?
|
Uses energy from H+ moving down electrochemical gradient and phosphorylates ADP.
|
|
What is the electron transport chain?
|
A series of electron carriers in the cell memebrane.
|
|
What does the electron transport chain do?
|
Oxidizes coenzymes.
|
|
What is the first carrier in the electron transport chain?
|
NADH dehydrogenase.
|
|
What happens to NADH and the first carrier in the electron transport chain?
|
NADH is oxidized to NAD+ and the first carrier is reduced.
|
|
What does NADH dehydrogenase do?
|
Reduces the next carrier.
|
|
What is the second carrier?
|
Flavin mononucleotide.
|
|
What else does NADH dehydrogenase do?
|
pumps H+ into the periplasmic space.
|
|
What happens to the electrons?
|
They pass through the electron transport chain.
|
|
What is the final electron acceptor?
|
Oxygen.
|
|
What happens to the H+ after re-entering the cell?
|
It binds with the final electron acceptor (fea), oxygen to form water.
|
|
What are often the final electron carriers in the electron transport chain?
|
Cytochromes
|
|
If cytochrome C is present, what happens?
|
Cytochrome oxidase catalyzes cytochrome C oxidation and oxygen reduction.
|
|
What does the oxidase test for?
|
Cytochrome oxidase
|
|
Why is the oxidase test useful?
|
It differentiates between Gram - rods
|
|
If oxidase test is positive what are you dealing with? Negative?
|
+ = Campylobactor (which causes food poisoning) and Pseudomonas.
- = Enterics. |
|
Where do electrons come from for the electron transport chain?
|
Catabolism
|
|
What is catabolism?
|
Break down of molecules to generate reducing energy.
|
|
What four forms of producing energy are we comparing?
|
Aerobic/anaerobic respiration, fermentation, and chemoautotrophy.
|
|
What is aerobic respiration?
|
The catabolism of polysaccharides and monosaccharides, proteins and lipids.
|
|
What is the final electron acceptor of Aerobic respiration?
|
Oxygen.
|
|
What is the equation for the Aerobic respiration of glucose?
|
C6H12O6 + 6O2 + 38ADP + 38PO4 --> 6CO2 + 6H2O + 38ATP
|
|
What are the four steps of Aerobic Resipiration of Glucose?
|
Glycolysis, Transition step, [TCA cycle, Kreb Cycle, and Citric Acid cycle], and the electron transport chain.
|
|
What happens in Glycolysis?
|
glucose is oxidized to pyruvate.
|
|
What are the products of Gylcolysis and where does each come from?
|
2 ATP (2 used, 4 produced) during substrate level phosphorylation, NADH during the electron transport chain, and 2 pyruvates from each one glucose
|
|
What are the four steps of Aerobic Resipiration of Glucose?
|
Glycolysis, Transition step, [TCA cycle, Kreb Cycle, and Citric Acid cycle], and the electron transport chain.
|
|
What occurs during the transition step of aerobic respiration?
|
Pyruvic acid is oxidized to acetyl CoA.
|
|
What does CoA stand for?
|
Coenzyme A
|
|
What are the products of the transition step and where do that come from?
|
NADH from the electron transport chain and acetyl CoA from the Kreb Cycle.
|
|
How many times does the TCA cycle repeat per one glucose?
|
twice.
|
|
What are the products of the TCA cycle and where do they come from?
|
CO2, 2 ATP (one/turn of cycle)...GTP (guanosine triphosphate), and NADH and FADH2 (reducing energy) from the electron trasport chain
|
|
What is the first step of fermentation?
|
Glycolysis.
|
|
What is the second step of fermentation?
|
Oxidation of the NADH from glycolysis.
|
|
What is the final electron/H+ acceptor in fermentation?
|
Pyruvate or pyruvate derivative.
|
|
How much energy is generated in fermentation as compared to Aerobic respiration?
|
Less.
|
|
Where does ATP formation occur in fermentation and in what amounts?
|
Substrate level phosphorylation and in small amounts.
|
|
How much oxygen is used during fermentation?
|
Oxygen is not used, but maybe be present.
|
|
What are the end products of fermentation?
|
Gases, acids, and neutral products.
|
|
What does the combination of products depend on?
|
The fermentation pathway.
|
|
What accounts for the energy difference between fermentation and aerobic respiration?
|
Fermentation does not have the electron transport chain or the Kreb Cycle.
|
|
What does the fermentation pathway of a microorganism during fermentation depend on?
|
The type of microorganism.
|
|
How do we detect carbohydrate fermentation?
|
pH indicators, Durham tubes, Ex. Phenol-red lactose/glucose medium
|
|
When detected carbohydrate fermentation, what would yellow mean?
|
Acidic and that fermentation occurred.
|
|
Name four fermentation pathways.
|
Lactic Acid, Ethanolic, Mixed-Acid, and Butanediol fermentation.
|
|
When does lactic acid fermentation occur?
|
When muscles run out of oxygen.
|
|
The end products of Lactic Acid fermentation are either:
|
homolactic or heterolactic.
|
|
What do homolactic and heterolactic mean?
|
only lactic acid, and lactic acid + CO2, and EtOH respectively.
|
|
Give examples of lactic acid fermentors:
|
Streptococcus (dental cavities), Leuconostoc (Sauerkraut), Lactobacillus (normal human gut flora...digestion).
|
|
What are the end products of Ethanolic fermentation?
|
CO2 and EtOH
|
|
Give an example of an Ethanolic fermentor.
|
Saccaromyces cerevisiae (brewers and bakers yeast).
|
|
Is yeast a pro or eukaryote.
|
fungi...eukaryote
|
|
What are the end products of Mixed-Acid fermentation?
|
ethanol, CO2, and H2, and then acetic, succinic, formic, and/or lactic acids.
|
|
What test can be used to distinguish Mixed-Acid fermentation?
|
Methyl Red Test (MR)
|
|
What will the results of an methyl red test look like?
|
Because methyl red is a pH indicator, basic = yellow and acid = red (different from usual).
|
|
What two species can the methyl red test distinguish between?
|
E. coli (MR+) and Enterobacter aerogenes (MR-)
|
|
What are the end products of Butanediol fermentation?
|
Butanediol and CO2
|
|
What test can be used to determine Butanediol fermentation?
|
Voges-Proskauer test (VP test)
|
|
What is the problem faced by the Voges-Proskauer test? The solution?
|
Butanediol is neutral, so it tests rather for acetoin, a butanediol precursor.
|
|
Between what two microorganisms does the Voges-Proskauer test distinguish?
|
E. coli (VP-) and Enterobacter aerogenes (VP+).
|
|
Enterobacter aerogens and E. coli are quite similar and live in a common environment, why would we want to distinguish between them?
|
E. coli is a fecal coliform, a fecal pollution indicator in the environment that is the pathogenic Enteric that lives the longest outside the gut where as Enterobacter aerogenes is non-pathogenic and nothing to worry about.
|
|
What is the final electron acceptor of anaerobic respiration?
|
Something other than oxygen.
|
|
What are 3 differences between anaerobic and aerobic respiration?
|
different carriers in electron transport chain, more ATP produced in aerobic, the final electron acceptor is different.
|
|
What type of reaction is anaerobic respiration?
|
A reduction.
|
|
What type of reduction is anaerobic respiration?
|
Nitrate or sulfate reduction.
|
|
Demonstrate a sulfate reduction.
|
SO4 --> H2S
|
|
What are the characteristics of the Sulfate Reduction products?
|
Anoxic sediments that smell bad and are a black color.
|
|
Demonstrate the denitrification reaction.
|
NO3-->N2 (gas)
|
|
What is the source of most atmospheric Nitrogen?
|
Denirification of bacteria.
|
|
What is the nitrogen cycle?
|
N2 <--> nitrogen fixation by bacteria <--> NH4+ <--> NO2- <--> Nitrification by bacteria <--> NO3- (plants like this) <--> denitrification of bacteria <--> N2
|
|
Show the reaction of Methanogenesis.
|
acetate --> CH4 (a green house gas...absorbs heat).
|
|
What type of organisms undergo mathanogenesis?
|
Methanogens such as Archaea which are obligate anaerobes.
|