The sum total of all chemical reactions is known as _____.
metabolism
Which of the following is correct?
Vitamins are most commonly required growth gactors and required in small amount.
What are macronutrients?
Carbon
potassium
Nitrogen
Sodium
Siderophores help transfer what nutrients across the cell membrane?
Iron
What describes culture media correctly?
In general, complex media contain yeast extract or meat extract
selective media contain compounds that selectively inhibit growth of some microbes, but not others
Differential media contain an indicator, usually a dye , that detects particular chemical reactions occur during growth
Sterilization refers to?
Absence of all microorganisms including viruses
There is a mixture of bacterial culture and a professor asks you to isolate lactose fermenting bacteria. Which of the fallowing media should be used to select lactose fermenting bacteria from the mixed culture and what would you expect to see on that media if lactose fermenting bacteria exist in the mixture?
MacConkey agar, pink colonies
If lactose fermentation on macConkeys does now exist but only Salmonella are present what ph would you expect to see on that media?
pH>7
Chemolithoautotrophs use ______ as an energy source and _____ as a carbon source.
Inorganic compounds, CO2
If delta G is positive _______
the reaction is endergonic and requires the input of energy
What is true of catalysts?
It changes reaction rate
What is true of enzymes?
They are biological catalysts and increase the rate of chemical reactions
They are typically proteins, although some RNAs have enzymatic activity
They are highly specific because of active site, the region of the enzyme that binds the substrate
What correctly describes redox reactions?
In an oxydation reaction occurs , a reduction reaction must also occur
What properly describes NAD+/NAGH reactions
They are recycled
They facilitate the redox reactions without being consumed
NADH dehydrogenase is a protein bound to inside surface of cytoplasmic membrane and its active site binds to NADH
What involves substrate-level phosphorylation to generate ATP
Phosphoenolpyruvate (PEP) to pyruvate
Net products of glycolysis are 2NADH, 2 ATP, and 2 pyruvates per one glucose molecule and net products of lactate fermentation are 2 NADH, 2 ATP, and 2 lactate molecule per one glucose molecule(T,F)
False
What is found in gluconeogenesis?
PEP-carboxykinase
pyruvate carboxylase
glucose-6-phosohate
In aerobic respiration what is the terminal electron acceptor?
Oxygen
Alkaliphite Bacillus firmus utilizes ______ to create membrane energetics.
Sodium motive force
One purpose of the TCA cycle is to generate NADH that will be used in the electron transfer chain. Another purpose of TCA cycle is to make some intermediates that can be used during biosynthesis reactions. (T/F)
True
Which of the following molecules is part of net products of the TCA cycle?
CO2
NADH
GTP
What correctly describes microbial culture?
In a chemostat, the growth rate is controlled by dilution rate
in a chemostat the growth yeild is controlled by the concentration of the limiting nutrients
In a batch culture, it is impossible to independently control both the growth yeild and rate
In general via aerobic respiration how many ATP can be generated from 1 NADH and 1 FADH respectively?
3 ATP/ 2 ATP
Organisms that live in the environments high in sugar as solute are called ___.
osmophiles
What is the correct order of transfer of electrons in the ETC.
FADH2 to quinones to cytochrome bc1 to cytochrome c to cytochromes a and a3
In thermophiles different modifications in cytoplasmic membranes can be observed for Bacteria and Archaea. Bacterial thermiphiles have lipid monolayer rather than bilayer, wherease archaeal thermophiles have lipids rich in saturated fatty acids that form a strong hydrophobic environment than do unsaturated fatty acids.(T/F)
False
Label these statements as (T/F)-----some microbes can grow in bioling water. Taq polymerase was isolated from a thermiphile and is used in the polymerase chain reaction technique. In gerneral mesophiles that have midrange temperature optima are found in warm blood animals. Mechanisms for combating low water activity in surrounding environments involve pumping internal solutes out to the environment
T,T,T,F
What statements are true regarding feedback inhibition?
Feedback inhibition is a mechanism for turning off the reactions in a biosynthetic pathway
In the feedback inhibition, end product of the pathway binds the first enzyme in the pathways
Isoenzymes are different enzymes that catalyze the same reaction, but are subject to different regulatory controls
Cryptic growth occurs ____.
as the number of cells being generated equals the number of cells dying
Direct microscopic counts of natural samples typically reveal for more microorganisms than are recoverable on plates of any giver culture conditions. Why does it happen?
Micrscopic methods count dead cells whereas viable methods do not
Different microorganisms in even as very small sample may have different requirements for resources and conditions in laboratory culture
Viable but non-culturable microorganisms are present
What factors influence microbial growth?
PH
water availability
oxygen
temperature
In microbial growth measure which of the following are advantages of turbidity measurements?
They typically do not require destruction of significant disturbance of samples
What are the limitations of microscopic counts?
Cannot distinguish between live and dead cells without staining
Debris in samples can be mistaken for cells
cell suspensions of low desity are hard to count
The amino group typically comes from inorganic nitrogen source obtained from the environment and is incorporated by glutamate dehydrogenase or glutamine synthetase(T/F)
True
The major shape-determining protein in prokaryotes is called _____.
MreB
which of the following matabolisms utilize electron transport/proton motive force?
Chemolithotrophy and respiration
Fatty acids are biosynthesized two carbones at a time using a(an) ______ that holds the growing fatty acids as it is being synthesized
acyl carrier protein(ACP)
In regulation of activity of biosynthetic enzymes, glutamine synthetase is regulated by adenosine monophosphate, which of the following describes correctly?
The amount of glutamine and GS activity is inversely correlated
In bacterial growth, generation time is dependent on ______.
growth medium and incubation conditions
What is true regarding the ETC
The net result of electron transfer is the generation of a pH gradient and an electrochemical potential across the membrane
Oxalacetate is important the formation og phosphoenolpyruvate in gluconeogenesis
ATP synthase complex converts proton motive force into ATP
In aerobic respiration, how many NADH are generated by the both glycolysis and TCA cycle per two glucose molecules?
20NADH
An energized state of a membrane created by a proton gradient and usually formed through action of an electron transfer chain is called _______.