Studied by 51 people
A growth medium that distinguishes among different groups of bacteria on the basis of their biological and growth characteristics on the medium is called a/an ___________ medium.
Transport
Differential
Selective
Enrichment
Differential
Square planar arrangement of cells that forms when round bacteria remain attached to each other during reproduction are called…..
Tetrads
Streptococci
Sarcinae
Staphylococci
Tetrads
The majority of nitrogen in soil and marine environments is fixed by….
E. coli
Symbionts
Free living bacteria and archaea
Organisms living w/in bacteria
Free living bacteria and archaea
Which of the following statements about ABC transporters is not true?
They can be used for import and export material for the cell
They are also responsible for multi-drug resistance
They require energy
They are found only in prokaryotes
They are found only in prokaryotes
Calculate the number of cfu/mL for the E. Coli sample.
2.78x10^7
The growth rate of a given species of microorganism is dependent on the composition of the medium in which it is grown.
T/F
True
Which of the following proteins represents a coupled transport system where two molecules travel in the opposite direction?
Symporter
Aquaporin
Efflux Pump
Antiporter
Antiporter
After you transferred 1mL from a 10^-6 dilution tube into a plate, you counted 207 colonies. How many CFU are present in 1 mL?
2.07x10^8
What does this graph represent?
Bacterial Growth in a chemostat
Bacterial growth at high temperature
Bacterial growth in closed culture
Bacterial growth in continuous culture
Bacterial growth in closed culture
A medium that has ingredients, such as yeast extract or casein milk proteins, which consist of a mixture of many chemical species in unknown proportions is commonly referred as
Complex medium
Synthetic medium
Differential medium
Selective medium
Complex medium
A growth medium that favors the growth of some microorganisms but inhibits the growth of other microorganisms is a ______ medium.
Neither selective nor differential
Selective
Selective and differential
Differential
Selective
You are measuring growth in a bacterial culture. The number of viable cells remained unchanged throughout the experiment but when you check the medium you found that the carbon source has been depleted (used up). In which phase of growth is the culture in?
Lag phase
Early log phase
Late log phase
Stationary phase
Death phase
Stationary phase
Which of the following element combinations include only macronutrients required in large quantities by many microbes?
C, O, S, Zi, Mn
S,O,Mg,Ca,K
H, N,K,Mg,Mo
P,H,S,Cu,Ni
S,O,Mg,Ca,K
Which of the following uses sunlight for energy and CO2 as a carbon source?
Photogeterotrophs
Chemoautotrophs
Photoautotrophys
Chemoheterotrophs
Photoautotrophys
Neisseria meningitidis are cultured on chocolate agar, a medium containing red blood cells that help cultivate the fastidious bacteria to detectable levels. What type of growth medium is chocolate agar based on the description?
differential
selective
enriched
selective and differential
enriched
The greater the concentration gradient, the faster the rate of diffusion
T/F
True
You are working with a culture medium X that only allows the growth of halophiles (salt-loving microbes). Among. the halophiles, mannitol fermenters will produce acid that turns the pH indicator in the medium to yellow while mannitol non-fermenters will not change the color of the medium.
Medium X is acting as a ______ medium.
enrichment
selective
differential
selective and differential
selective and differential
If you start with 4 cells in an exponetial phase and divides to 10 cells every cell division, the total number of cells after “n: number of generations is proportional to_____.
4x10^n
10x4^n
4xn^10
40
4x10^n
Calculate the colony forming units in 1 mL of the E. coli sample.
5.7x10^7
Calculate the colony forming units in the whole 5 mL of the E. coli sample.
2.85x10^9
One cell with generation time of 30 mins is inoculated into a culture medium. How many cells are there after 2 hours. (assuming all cells divide by binary fission in log phase and remained viable)
96
180
16
32
16
Bacteria were transferred into a nutrient broth and placed in an incubator. The number of bacteria was determined at the end of each day: at start =10 bacteria, end of day= 20 bacteria, end of day 2= 40 bacteria, end of day 3= 80 bacteria, day 4= 160 bacteria.
How many bacteria at end of Day 20?
more than 10 million
1,280,000
6400
640
more than 10 million
At 4:00pm a closed flask of sterile broth is inoculated with 10,000 cells. At 8:00 pm the log phase culture has population of approx. 41 million cells. The estimated number or generations that has occurred is_______.
Assume that the culture maintained log phase and every cell actively divided the whole time. Round.
5
12
21
27
12
Shortest lag period would most likely be observed if a culture is transferred_______.
to a medium at a different temp
from a complex medium to a fresh complex medium
to a medium at a different pH
from a complex medium to a minimal medium
from a complex medium to a fresh complex medium
The figure below shows the growth curve of a bacteria in a batch (closed) culture. In which phase would you expect to find amount of carbon decreasing while. the. number of viable cells increasing?
a
b
c
d
b
In cultures without oxygen, if streptococcus pyogenes decided to undergo fermentation, what happens to the electrons carried by NADH from glycolysis?
will be donated back to glucose
will be lost to the media
will be donated to pyruvates
will be donated to electron transport system
will be donated to pyruvates
Fermentation produces more energy than anaerobic respiration.
T/F
False
Oxygen is always required for the regeneration of NAD+ from NADH.
T/F
False
Which is not an end product of fermentation?
carbon dioxide
propionate
acetone
pyruvate
pyruvate
You feed E. coli 3 glucose molecules. How many ATP are created only through substrate level phosphorylation?
6
10
8
12
12
The enzyme pyruvate kinase catalyzes the conversion of PEP to pyruvate. The phosphate group is transferred to ADP to form ATP. This is an example of:
ATP synthesis through substrate level phosphorylation
ATP synthase by oxidative phosphorylation
ATP synthesis through substrate level phosphorylation
Why do bacterial cells need fermentation?
Synthesize more NADH
Produce ATP by substrate level phosphorylation
produce pyruvate for transition steps
Recycle NADH back to NAD+
Recycle NADH back to NAD+
The Entner-Dourdoroff (ED) pathway and the pentose Phosphate Pathway (PPP) both produce NADH.
T/F
False
Which of the following is NOT correct with respect to the redox pair NAD+/NADH?
NADH can accept electrons from an electron transport system
The reduced, nonaromatic ring of NADH is at a higher energy than the aromatic ring of NAD+
the nicothinamide ring is a relatively stable aromatic structure
the nicotinamide ring is heteoaromatic because it has a noncarbon atom in its 4th position.
NADH can accept electrons from an electron transport system
The enzyme pyruvate kinase catalyzes the conversion of PEP to Pyruvate. The phosphate group is transferred to ADP to form ATP. This reaction is an example of…
ATP synthesis through substrate level phosphorylation
ATP synthesis by oxidative phosphorylation
ATP synthesis through substrate level phosphorylation
The following is a condensed representation of the TCA cycle.
What is the name of the intermediate labelled 6?
oxaloacetate
succinyl-CoA
Acetyl-CoA
Citrate
Citrate
E. coli could yield a max of 38 ATP per each glucose molecule by aerobic respiration. The same E. coli could also yield similar amount of ATP per each glucose molecule using fermentation as long as they have plenty of resources.
T/F
False
Before pyruvate can enter the TCA cycle it must be transformed into what molecule?
pyruvate dehydrogenase
oxaloacetate
Acetyl-CoA
Malate
Acetyl-CoA
The glyoxylate Bypass (shunt) can be utilized by some organisms when carbon sources are limited. The bypass incorporate a second molecule of Acetyl-CoA to form succinate and ______ molecules.
isocitrite
oxaloacetate
malate
pyruvate
malate
Which of the following pathways would be fully operational only in respiring bacteria?
fermentation
PPP
TCA
Glycolysis
TCA
How many electron carriers in total are created from just the TCA cycle from 2 glucose molecules?
16
12
8
24
16
Production of ATP by ATP synthase directly depends on. which of the following?
GTP
Proton motive force
electron carrier force
neutron motive force
Proton motive force
Which of the following is not a component of E. coli Electron Transport System?
NADH Dehydrogenase (oxidoreductase)
Terminal oxidase
Cytochrome oxidase complex
mobile electron carrier
Cytochrome oxidase complex
Anaerobic respiration uses an electron transport system while fermentation does not utilize an electron transport system.
T/F
True
Oxygen is always required for oxidation of NADH to NAD+.
T/F
False
Which of the. following statements about anaerobic respiration is true?
it does not require ETS
use oxidized ions of nitrogen, and sulfur as their final electron acceptor
it generates only 2 ATP per single glucose
uses oxygen as a final electron acceptor
use oxidized ions of nitrogen, and sulfur as their final electron acceptor
If you feed Streptococcus pyogenes 5 glucose molecules in aerobic condition, what is the maximum theoretical amount. of ATP. produced? (aerobic respiration)
160
190
125
150
190
Which group of microorganisms are most likely to spoil a fish kept at a refrigerator (low temp)?
psychrophiles
halophiles
anaerobes
thermophiles
psychrophiles
The following data show growth of 2 bacteria on different media.
The table shows that S. aureus is an?
alkalophile
anaerobe
mesophile
halophile
halophile
The term aerotolerant anaerobe refers to an organism that
use oxygen if present in high concentration
requires less oxygen than is present in air
use oxygen but prefers nitrogen compounds
does not use it oxygen and is not affected by it
does not use it oxygen and is not affected by it
Which of the following determines if microorganisms are going to use oxygen or not?
their ability to use oxygen to oxidize glucose
their ability to use oxygen during glycolysis
their ability to use oxygen as a terminal electron acceptor
their ability to have enzymes that deals with ROS
their ability to use oxygen as a terminal electron acceptor
their ability to have enzymes that deals with ROS
Which shows phenol red test result of heterolactic fermentation?
left tube (yellow one)
Note 
Flashcard (107)