Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Microbio > Exam 2 review > Flashcards

Exam 2 review Flashcards

1
Q

What is catabolism (decomposition)

A

A chemical pathway that RELEASES energy (EXERGONIC REACTION) from BREAKING down more complex REACTANTS into less complex PRODUCTS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is anabolism (synthesis)

A

A chemical pathway that USES up energy (ENDERGONIC REACTION) to CREATE more complex PRODUCTS from less complex REACTANTS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the difference between exergonic and endergonic

A

-exergonic reactions release energy
-endergonic reactions uses up energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is oxidation

A

-lose electrons
-electron donor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is reduction

A

-gain electrons
-electron acceptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is hydrolysis

A

-Breaking of a chemical bond using a water molecule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is phosphorylation

A

-Addition of a phosphate group to any molecule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is a catalyst

A

-speeds up reaction without being consumed by the reaction
-stays the same

NOTES:
-enzymes are proteins that act as catalysts for chemical reactions inside the cells
-all enzymes are catalysts
-enzymes may combine molecules, separate the components or rearrange them
-The molecules that is changed by the enzyme is a substrate
-the pocket in the enzyme that binds the substrate is active site

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Which enzyme is responsible for the
following reaction?
What is the purpose of this reaction?
Is this catabolism or anabolism?

A

-amylase
-breaks down bigger pieces into smaller pieces so that the cell can use it
-catalyst

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How do enzymes help with a reaction

A

enzymes facilitate chemical reactions by lowering the ACTIVATION ENERGY

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is activation energy

A

the energy requires to initiate a chemical reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

-Which of the following labeled arrows shows the amount of energy saved going from reactants to products by using a catalyst?
-Which is the activation energy with no enzyme?
-Is this reaction exergonic or endergonic?

A

-b
- A
-endergonic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Enzymes bind to their substrate and facilitate chemical reactions and change the substrate without being altered themselves

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the induced fit model

A

the shape of the enzyme changes as the substrate binds creating a perfect alignment and ideal microenvironment for the reaction to occur

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what are coenzymes or cofactors

A

-non-protein helpers that bind enzymes and are required for the function of some enzymes
-interact with the active site of an enzyme to improve its performance

EX: cofactors: Fe^2+ and Mg^2+ (inorganic)
EX: coenzymes: vitamis, ATP, and NADH (organic)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is competitive inhibitors

A

They mimic the substrate and by binding to the active site, they block the binding of the substrate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is allosteric inhibition and activation

A

When the enzyme’s activity is inhibited or activated by binding of the regulatory molecule to a site separate from the active site

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is metabolic pathway

A

A set of enzymatically controlled reactions that result in a final product

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is a peptide bond

A

-covalent bonds that join amino acids together
-between the amine group of one amino acid and the carboxyl group of the next amino acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the factors that affect enzymatic activity

A

TEMPERATURE
-molecules move faster as temperature increase
-DENATURATION: the unfolding of a protein’s secondary or higher structure

pH
-too basic or too acidic environments can also cause denaturation

SUBSTRATE CONCENTRATION
-SATURATION POINT: the point at which the rate of enzymatic activity does not increase with increased substrate concentration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

In an enzymatic reaction, the ______ binds to the _______.
A. Substrate; active site
B. Active site; catalyst
C. Catalyst; active site
D. Activation energy; substrate

A

A. substrate; active site

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How is this enzyme regulated?

Sulfanilamide is an antimicrobial drug used to treat yeast and bacteria infection. It is Structurally similar to PABA which is the substrate of the enzyme responsible for of folate. Sulfanilamide binds to the same active site on the enzyme as the substrate and inhibits the enzyme.

A. Allosteric Inhibition
B. Competitive Inhibition
C. Feedback Inhibition
D. Allosteric Activation

A

B competitive inhibition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How is production of tryptophan regulated

A

C feedback inhibition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How does penicillin work

A

B competitive inhibition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What kind of enzyme regulation

A

1) D. allosteric activation
2) A. Allosteric inhibition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what pathway does most microbes use

A

embden-meyerhof-parnas (EMP) (glycolysis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is enter-doudoroff pathway

A
  • Alternative to glycolysis
  • Produces NADPH and ATP
  • Produces Pyruvate
  • Occurs in Pseudomonas, Rhizobium, and Agrobacterium
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is Pentose phosphate pathway

A
  • Operates simultaneously with glycolysis
  • Produces NADPH (electron carrier molecule)
  • No ATP is produced
  • Produces Ribose 5-phosphate which is the precursor for DNA/ RNA
29
Q

How is ATP generated in Glycolysis?
A. Substrate Level Phosphorylation
B. Oxidative Phosphorylation
C. Photophosphorylation

What are the products of Glycolysis?
Where does it occur in prokaryotes
and eukaryotes?

A

-A
-the end products are 2 ATP ,2 NADH, 2 pyruvates

30
Q

PYRUVATE OXIDATION
What is oxidized and what is reduced?
What are the products?
Where does it occur in prokaryotes and eukaryotes?

A

-pyruvate is being oxidized
-NAD+ is being reduced
-products from glycolysis of 2 molecules of pyruvate are 2 acetyl CoA +2 NADH + 2 CO2
-occurs in mitochondrial matrix in eukaryotes and in cytoplasm in prokarytoes

31
Q

What are the products of the KREBS cycle and where does it occur in prokaryotes and eukaryotes

A

-2 molecules of acetyl CoA -> 6 NADH + 2 FADH2 + 2 ATP + 4 CO2 + 2 CoA
-occurs in the cytoplasm in prokaryotes and mitochondrial matrix in eukaryotes

32
Q

True or False? Coenzyme A is consumed whenever pyruvate is fully oxidized.

A

false

33
Q

What are the two stages of oxidative phosphorylation

A

-electron transport chain (ETC)
-chemiosmosis

34
Q

What is the ELECTRON TRANSPORT CHAIN

A

A series of complexes (proteins and others) that use redox reactions to transfer electrons down
a chain, coupling those reactions to move protons (H+ ions) across a membrane

35
Q

What is chemiosmosis mechanism

A

the use of facilitate diffusion of protons to synthesize ATP

36
Q

In the ETC,
-where does it occur in prokaryotes and eukaryotes
-what is the electron donor
-what is the final electron acceptor

A

-eukaryotes, occurs in inner mitochondria membrane
-prokaryotes, occurs in cell membrane
-NADH is the electron donor
-final electron acceptor is oxygen

37
Q

glycolysis uses 2 ATP and creates 4 ATP, NET ATP is 2

A
38
Q

Thiobacillus denitrificans produce ATP with no oxygen. By using NO3-
and producing NO2- which is eventually converted into N2.

This an example of
A. Aerobic respiration
B. Anaerobic respiration
C. Fermentation

A

B. anaerobic respiration

39
Q

-How is NAD+ generated in fermentation, aerobic and anaerobic respiration?
-Why is this important?
-How many ATPs are produced in fermentation?
-What is the final electron acceptor?

A

-oxidation of NADH
-required for glycolysis
-2 ATPs
-organic molecule usually pyruvate

40
Q

What can be used as fuels for cellular respiration

A

-glucose, carbohydrates, proteins, and fats

41
Q

Noncyclic Photophosphorylation
-what is the electron donor
-what is the electron acceptor
-what are the products

A

-water is the electron donor
-NADP is the electron acceptor
-the products are O2, ATP, and NADPH

42
Q

what is the difference between oxygenic and anoxygenic photosynthesis

A

-oxygenic photosynthesis: water is the electron donor and it produces glucose, oxygen, and water
-anoxygenic photosynthesis: produces carbohydrate and water

43
Q

What RuBisCo

A

The enzyme ribulose biphosphate carboxylase used in fixation for the Calvin Cycle.

44
Q

What is fixation in the calvin cycle

A

RuBisCo is used to catalyze the addition of CO2 to ribulose biphosphate and results in the production of 3 phosohoglycerate

45
Q

what is reduction in the Calvin cycle

A

ATP and NADPH from the light dependent reactions are used to convert 3 PGA into glyceraldehyde 3- phosphate

46
Q

what is regeneration in the Calvin cycle

A

ATP is used to convert the remaining G3P to RuBP

47
Q

what is the nitrogen cycle an what are the steps

A

-transfer of nitrogen from the atmosphere to the soil and living things and back to the atmosphere
steps
1. fixation (converts N2 gas to ammonium)
2.ammonification (converts organic nitrogen into ammonium)
3.nitrification (converts ammonium into nitrite then to nitrate)
4.denitrification (converts nitrogen in the form of NO3- back into N2 gas)

48
Q

What is substrate level phosphorylation

A

when phosphate group on one molecule is transferred to ADP to product ATP

49
Q

What is kinase

A

an enzyme which phosphorylates ADP and make ATP

50
Q

How is ATP generated in living cells

A

-substrate level phosphorylation
-oxidative phosphorylation
-photophosphorylation

51
Q

-Which molecule is an electron donor and which is the electron acceptor?
-Which is oxidation and which is reduction reaction?

A

-NADH is the electron donor
-NAD+ is the electron acceptor
-from left to right, it is an oxidation reaction
-from right to left, it is a reduction reaction

52
Q

-Which reaction is exergonic and endergonic? –Which reaction is spontaneous and which is not?

A

-The left reaction is exergonic and spontaneous
-The right reaction is endergonic and not spontaneous

53
Q

What is metabolic diversity

A

classification of microbes based on carbon, electron, and energy sources

54
Q

What are the energy sources of metabolic diversity

A

Phototroph: energy obtained from light

Chemotroph: energy obtained from breaking chemical bonds

55
Q

What are the electron sources of metabolic diversity

A

Organotroph: electrons and/or hydrogen ions from organic compounds

Lithotroph: electrons and/or hydrogen ions from inorganic source

56
Q

What are carbon sources from metabolic diversity

A

Autotrophs: convert inorganic CO2 from the atmosphere into organic carbon compounds (EX plants and cyanobacteria)

Heterotroph: carbon obtained from organic molecules in other organisms (EX humans Ecoli)

57
Q

What does this result mean?

A

-obligate aerobe
-requires oxygen

58
Q

What does this result mean?

A

-obligate anaerobe
-killed by oxygen

59
Q

What does this result mean?

A

-facultative anaerobe
-prefer oxygen but can survive without it

60
Q

What does this result mean?

A

-areotolerant anaerobe
-indifferent to oxygen

61
Q

What does this result mean?

A

-microaerophiles
-require a certain oxygen concentration

62
Q

For standard plate counting what numbers are acceptable

A

30-300

63
Q

A plate has 72 colonies with a total dilution factor of 10-7. 0.1 mL was pipetted onto the plate. What was the original CFU/mL concentration of the sample

A

72 cells/ 0.1mL=720 CFU
720(10/7)=1,028 or 1.03 x 10^3

64
Q

What is the purpose of the starch hydrolysis test and what do the results mean

A

-used to determine if bacteria produced amylase
-halo means positive, no halo means negative

65
Q

What is the purpose of the caseinase test and what do the results mean

A

-to detect is caseinase is present
-positive result will show clearing around bacteria growth
-negative result will show now clearing

66
Q

What is the purpose of the gelatinase test and what do the results mean

A

-To determine if the bacteria is able to secrete gelatinase
-positive will show liquid in test tube
-negative will show no liquid/will be solid in test tube

67
Q

What is the durham test tubes used for and how do you interpret the results

A

-used to detect carbohydrate fermentation
-bubbles mean positive for fermentation and acidic
- red to yellow means positive for fermentation

68
Q

what are coliforms

A

bacteria used to detect fecal contamination in water

Microbio (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions