Microbiology Exam 2 Ch. 6, 7, 8, 9
How many ATP are produced in Kreb's cycle alone per pyruvate?
1
How many ATP are used up in Glycolysis per glucose?
2
How many CO2 molecules are produced in the preparatory steps/conversions per glucose in the Krebs Cycle?
2
How many NADH are produced by Glycolysis per glucose?
2
How many net ATP are produced by Glycolysis alone per glucose?
2
How many NADH are produced by the matrix reactions per pyruvate in the Krebs Cycle?
4
If 2 glucose molecules are being broken down in aerobic conditions, how many ATP will Kreb's cycle alone produce?
4
DNA replication occurs in what direction:
5' to 3'
What is NAD+? What does NAD+ accept during this conversion? What type of reaction occurred at this step?
A cofactor (co-enzyme)/electron carrier. It carries an electron (as well as a hydrogen ion (proton)); An oxidation-reduction reaction.
What is occurring as intermediate 6 is converted into intermediate 7 in glycolysis? What is produced? How many times does this happen?
A dephosphorylation reaction. A phosphate group is given to ADP to make ATP (substrate level phosphorylation). Twice.
What does ADP accept during the reaction between Intermediate 5 and Intermediate 6 of the Krebs cycle? What does ADP become?
A phosphate group, ATP.
What are the end products of the Krebs Cycle? Of these end products, which one(s) is/are the key to aid in the production of the most energy for the cell?
ATP, NADH, FADH2, CO2. NADH and FADH2 are the keys.
What is the 2 carbon molecule that enters the Krebs cycle? What enzyme produces this intermediate? What is produced in addition to this 2 carbon molecule?
Acetyl-CoA. Pyruvate dehydrogenase. Carbon dioxide (CO2).
What does FAD+ accept during the reaction between intermediate 6 and intermediate 7 in the Krebs cycle?
An electron (and therefore a proton).
What is FAD+?
An electron acceptor/coenzyme.
When going from intermediate 2 to intermediate 3, what does NAD+ accept during this conversion in the Krebs cycle? What molecule is gaining electrons and what molecule is losing electrons? What does NAD+ become?
An electron, NAD+ gains an electron (being reduced) and Intermediate 2 is losing the electrons (being oxidized). NAD+ becomes NADH+H+
What type of reaction occurred when FAD+ became FADH2? What molecule is gaining electrons and what molecule is losing electrons?
An oxidation-reduction reaction in which FAD+ is gaining electrons (being reduced) and intermediate 6 is losing electrons (being oxidized).
Sterilization/disinfection of the human skin.
Antisepsis
Chemical agent that kills the bacterial target
Bactericidal
Chemical agents that prevent the growth of bacteria on tissues or on objects in the environment
Bacteriostatic
Some steps in the Krebs Cycle have enzymes that strip the intermediate of a carbon atom. What is the carbon molecule that is produced that contains the carbon atom (hint: it is also an end product that is released from the cell)?
CO2
The carbon that is in a glucose molecule ultimately ends up in which carbon end product of aerobic respiration?
Carbon dioxide
DNA nucleotide base pairs ______ each other.
Complement
Which two factors must be determined for each germicide to ensure that it is having the appropriate and optimal effect?
Concentration and contact time
Where does the electron transport chain take place in eukaryotes? In prokaryotes?
Cristae of the mitochondria, cell membrane
Where does transcription happen in prokaryotes? In eukaryotes?
Cytoplasm, nucleus
Dyes will interact and disrupt which two cellular components?
DNA and cell membrane
Enzyme responsible for adding additional nucleotides:
DNA polymerase
Cleansing technique that mechanically removes microorganisms as well as other debris to reduce contamination to safe levels.
Decontamination (sanitization)
Vegetative cells gradually become dehydrated.
Desiccation
Obligate aerobes will:
Die in the absence of oxygen
Physical process or a chemical agent to destroy vegetative pathogens and toxins but not bacterial endospores.
Disinfection
Which type of organism could potentially serve as normal flora?
Ectoparasites and Endoparasites
The NADH and FADH2 produced in the matrix reactions carry __________ to ____________ reactions.
Electrons; ETS
What purpose does the cell typically use micronutrients for?
Enzyme function and protein structure
What do the arrows represent?
Enzymes catalyzing reactions, substrate is the intermediate at the tail of the arrow, product is the intermediate at the head of the arrow.
What are the possible end products of anaerobic respiration?
Ethanol, lactate, acetate
What Does FAD+ become when it accepts an electron?
FADH2
All bacteria have the same generation time. True or false?
False
Binary fission occurs in a linear fashion in which one cell becomes two, two becomes four, etc. True or false?
False
Freezing will kill most microbes. True or false?
False
In an anaerobic environment, which set of reactions directly follow Glycolysis?
Fermentation
Use thin membrane to filter out particles, effective method to remove microbes from air and liquids.
Filtration
What physical method would one use to sterilize liquid antibiotics?
Filtration
Which one of the following is the 3rd molecule in Glycolysis and what is the phosphorylated intermediate that glucose is converted into during the initial steps of glycolysis?
Fructose-1,6-biphosphate
The starting carbon source of aerobic respiration is ______.
Glucose
What is the carbon source for anaerobic respiration?
Glucose
What is the carbon source for fermentation?
Glucose
Of the three pathways in aerobic respiration, which one occurs in the cytoplasm of both prokaryotes and eukaryotes?
Glycolysis
What is the pathway in fermentation?
Glycolysis
Which of the biochemical pathways does NOT require oxygen?
Glycolysis and fermentation
What pathways are involved in anaerobic respiration?
Glycolysis, Krebs Cycle, and electron transport chain
List the 3 pathways involved in aerobic respiration:
Glycolysis, the Krebs cycle, and the electron transport chain
What is the number one method for reducing the number of pathogens used during medical asepsis?
Handwashing
Which physical method causes proteins to coagulate and denature, therefore leading to cell death?
Heat
Acquiring DNA laterally from another bacteria
Horizontal Gene Transfer
Result from exposure to known mutagens:
Induced mutations
List the compounds that can be used at the end of the electron transport chain during anaerobic respiration.
Inorganic molecules: iron, sulfur, chromium, uranium, etc.
What is the purpose of oxygen during aerobic respiration?
It accepts the electrons that are shuttled along the electron transport chain so that the chain can keep accepting electrons.
What are the terminal electron acceptors in fermentation?
Lactate, succinate, acetate, ethanol
Where does Kreb's cycle occur in eukaryotes? In prokaryotes?
Matrix of mitochondrion, cytoplasm
Physical or chemical agents that disrupt DNA.
Mutagens
Any change to the nucleotide sequence:
Mutation
List the two coenzymes involved in the oxidation-reduction reactions that occur during catabolism (respiration).
NAD and FAD
What is a reduced electron carrier that carries electrons to the ETS?
NADH
When going from intermediate 5 to intermediate 6, NAD+ is converted into __________.
NADH+H+
What end product(s) from the Krebs cycle will be used in the electron transport chain? What are they carrying?
NADH, FADH2, electrons to the electron transport chain.
One colony begins with:
One cell
What is the terminal electron acceptor in anaerobic respiration?
Organic compounds (acids and alcohols)
Adding large amounts of salt or sugar to foods creates a hypertonic environment. Pickling, smoking, and drying foods have been used for centuries to preserve foods.
Osmotic pressure
What is the Kreb's cycle "acceptor" molecule that begins the cycle?
Oxaloacetate
What is the 4 carbon intermediate that initially binds with the 2 carbon intermediate produced after glycolysis? What 6 carbon molecule is subsequently generated that starts the Krebs cycle and is considered the first intermediate?
Oxaloacetate (intermediate 8 at the end of the Krebs cycle.) Citrate (6-C molecule)
What is the terminal electron acceptor of aerobic respiration?
Oxygen
Which one of the following molecules in Glycolysis donates a phosphate group to ADP to produce ATP?
Phosphoenolpyruvate
During glycolysis, glucose is converted into this 3 carbon compound.
Pyruvate
Which 3-carbon molecule is a final product of Glycolysis?
Pyruvate
What is the enzyme in transcription?
RNA polymerase
Energy emitted from atomic activities - gamma rays, X-rays, ultraviolet
Radiation
Produce a mutation that does not effect the protein's function:
Silent mutations
What type of transport involves the movement of molecules directly across the membrane along a concentration gradient?
Simple diffusion
What happens if oxygen is depleted during aerobic respiration? What process occurs?
Some organisms will shift to undergo fermentation
A mutation that occurs on its own during replication is a:
Spontaneous mutation
Process that destroys or removes all viable microorganisms.
Sterilization
How does a cell make energy using anaerobic respiration?
Substrate level phosphorylation
Where does glycolysis occur in Prokaryotes? In Eukaryotes?
The cytoplasm, both prokaryotes and eukaryotes
In analyzing the electron transport chain, where is the potential energy stored that is used by ATP synthase to make ATP ?
The higher concentration of protons just outside the cell membrane
When selecting a process or agent, what must you initially determine in order to select the best method?
The target organism(s), resistance of target organism(s), if you need an agent/process that is bacteriostatic or bactericidal.
What is the main difference between anaerobic respiration and aerobic respiration?
The terminal electron acceptor
Which characteristic of enzymes allow them to be recycled and used to carry out the same reaction multiple times?
They are not used up or changed by the reaction
What is the main purpose of fermentative pathways?
To regenerate NAD+
RNA polymerase reads a gene
Transcription
Some bacteria can readily take up fragments of DNA. These bacteria can undergo this readily.
Transformation
Bacterial cells in low nutrient environments may not be actively dividing. This may limit some of the targets used for antimicrobial treatment. True or false?
True
Bacterial cells will continue to divide at a steady rate as long as conditions are favorable and nutrients are available. True or false?
True
Detergents work by inserting itself into the cell membrane of organisms and causing cell lysis. True or false?
True
Endocytosis is typically known to be a function of eukaryotic cells. True or false?
True
Metabolism includes chemical reactions in the cell that contribute to macromolecule synthesis and energy production (i.e. ATP). True or false?
True
Mixed cultures and organisms in a biofilm have a higher probability of being more difficult to kill than a pure culture. True or false?
True
What is the carbon end product at the end of glycolysis? How many are produced? What are the other two end products produced?
Two Pyruvate molecules. ATP, NADH.
The molecule responsible for matching and bringing the next amino acid to the growing peptide is:
tRNA