Microbiology ch. 6
The energy released during the reactions of glycolysis is used to form A. Adenine triphosphate B. Glycerol C. Guanine triphosphate
A. Adenine triphosphate
In bacteria, protons received from NADH A. are transported (or pumped) through the membrane to the outside of the cell. B. act as coenzymes. C. are passed along the electron transport chain along with the electrons. D. are the terminal electron acceptors.
A. Are transported through the membrane to the outside of the cell
The synthesis of ATP via ATP synthase, driven by a proton motive force, is called A. chemiosmosis. B. cyclophosphorylation. C. substrate-level phosphorylation. D. glycolysis. E. the TCA cycle.
A. Chemiosmosis
Which of the following is NOT a catabolic process? A. Protein synthesis B. Fermentation C. TCA cycle D. Glycolysis
A. Protein synthesis
What are two fundamental tasks that all cells must accomplish to grow? a. synthesize new parts and harvest energy to power reactions b. mate and produce offspring c. consume food and digest food
A. synthesize new parts and harvest energy to power reactions
Where does the TCA cycle take place in bacteria? A. Cytoplasm B. Mitochondria C. Cell membrane
A. Cytoplasm
oxidizes an acetyl group to release two molecules of CO2; generates some ATP and precursor metabolites and the most reducing power of all the central metabolic pathways
TCA cycle
A culture of bacteria is breaking down sugars to yield energy. This is best described as ________. A. biosynthesis B. catabolism C. anabolism D. metabolism
B. Catabolism
Where do NADH and FADH2 go after being produced in the TCA cycle? A. Substrate-level phosphorylation B. Electron transport chain C. Calvin cycle
B. Electron transport chain
Glycolysis is the central metabolic pathway that involves the breakdown of A. Fatty acids B. Glucose C. Starch
B. Glucose
The TCA cycle occurs after A. The Calvin cycle B. Glycolysis C. Electron transport chain D. Fermentation
B. Glycolysis
The main purpose of cellular respiration is to A. Produce CO2 B. Produce energy C. Produce glucose
B. Produce energy
In the electron transport chain, protons are pumped across the cell membrane. This results in A. the loss of electrons. B. the formation of a proton motive force. C. the reduction of NADH. D. the creation of water.
B. The formation of a proton motive force
A hydrogen atom consists of A. a variable number of protons and electrons. B. a proton and several electrons. C. a proton and an electron. D. protons only. E. electrons only.
C. A proton and an electron
Consider how an aerobically respiring bacterial cell uses glycolysis, the TCA cycle, and oxidative phosphorylation to break apart and oxidize glucose. What are the three main benefits these central metabolic pathways yield to the cell? A. ADP, carbon dioxide, and water B. ATP, glucose, and carbon dioxide C. ATP, reduced electron carriers, and precursor metabolites D. Oxygen, fermentation, and precursor metabolites E. ATP, oxidized electron carriers, large carbon polymers
C. ATP, reduced electron carriers and precursor metabolites
Consider the biochemical pathway: A → B → C Enzyme 1 catalyzes A → B Enzyme 2 catalyzes B → C If enzyme 2 is inactive, which of the following compounds will accumulate? A. B and C B. A and B C. B only D. C only E. A only
C. B only
Which of the following contain a metal ion which can accept and donate electrons? A. Quinolone B. Chelators C. Cytochromes
C. Cytochromes
Streptococcus pneumoniae lacks an electron transport chain. Therefore, S. pneumoniae generates ATP via _________. A. oxidative phosphorylation B. aerobic respiration C. fermentation
C. Fermentation
In eukaryotic cells undergoing respiration, protons are pumped A. across the cytoplasmic membrane. B. from inside the mitochondria to the cytoplasm. C. from the mitochondrial matrix to the region between the inner and outer mitochondrial membranes (intermembrane space). D. from inside the cell to outside the cell.
C. From the mitochrondiral matrix to the region between the inner and outer mitochondrial membranes
The two 3-carbon molecules that glucose is split into during glycolysis are converted through a series of steps ending in what 3-carbon molecules? A. Citric acid B. Acetyl-CoA C. Pyruvate
C. Pyruvate
In aerobic respiration, oxygen acts as A. a coenzyme. B. one of the electron carriers, passing electrons down the ETC. C. the terminal electron acceptor. D. a reducing agent.
C. The terminal electron acceptor
T/F: whenever a molecule is oxidized, another molecule must be reduced
True
Lipid-soluble organize molecules that move freely in the membrane; includes one that serves as a source of vitamin K for humans and other mammals
Quinones
energy from exergonic reactions is used to create a proton motive force that drives the addition of P to ADP
oxidative phosphorylation
breaks down glucose, although primary role is production of NADPH and two precursor metabolites for use in biosynthesis
pentose phoshphate pathway
The sun's radiation energy and an electron transport chain create a proton motive force that drives the addition of P to ADP
photophosphorylation
Some enzymes require a cofactor or a coeznyme in order to be active. What is the difference between cofactors and coenzymes? A. Cofactors are non-protein components that assist enzymes and are typically trace elements; coenzymes are organic cofactors that loosely carry molecules or electrons. B. Cofactors transfer molecules or electrons from one compound to another while coenzymes are trace elements that assist in enzyme function. C. Cofactors are non-protein molecules while coenzymes are composed of amino acids. D. Coenzymes are non-protein molecules while cofactors are composed of amino acids.
A
Steps of the Central Metabolic Pathway
1. Glycolysis 2. Pentose Phosphate pathway 3. TCA Cycle 4. Cellular respiration 5. Fermentation Gary Put Toes on Carries Face
For each glucose molecule broken down by glycolysis, how many NET ATP molecules are produced?
2
TCA cycle has how many ATP?
22
Glycolysis has how many ATP?
6
During the electron transport chain, ATP will be made from A. ADP + Pi B. ADP + H2O C. ADP + 2Pi
A. ADP + Pi
In prokaryotic cells, the electron transport chain (ETC) is located in the ___________, whereas in eukaryotic cells, the ETC is located in the ____________. A. cytoplasmic membrane; inner membrane of mitochondria B. cytoplasm; mitochondrial matrix C. periplasmic space; cytoplasmic membrane D. cytoplasmic membrane; outer membrane of mitochondria
A. Cytoplasmic membrane; inner membrane of mitochondria
Consider the biochemical pathway: A → B → C Enzyme 1 catalyzes A → B Enzyme 2 catalyzes B → C Enzyme 1 can utilize A. only A as a substrate. B. either A or B as substrate, but c. not both. D. neither A nor B as substrate. E. both A and B as substrates. F. only B as a substrate.
A. Only A as a substrate
Removing the electron transport chain of E. coli would A. prevent oxidative phosphorylation. B. interfere with the function of its mitochondria. C. prevent glycolysis.
A. Prevent oxidative phosphorylation
_________ refers only to energy-requiring metabolic processes that result in the biosynthesis of macromolecules and cellular structures.
Anabolism
In bacteria, proton pumps are protein complexes that A. move protons from the exterior of the cell to the interior. B. pump protons and electrons through the cell membrane. C. move protons from the interior of the cell to the exterior. D. synthesize water from hydrogen and oxygen. E. break down water into hydrogen and oxygen.
C. Move protons from the interior of the cell to the exterior
Cells obtain energy by ________ food molecules such as glucose. A. redoxing B. phosphorylating C. oxidizing D. reducing E. anabolizing
C. Oxidizing
Enzymes are usually ________. A. nucleic acids B. lipids C. proteins D. carbohydrates E. steroids
C. Protiens
metabolic wastes of Lactococcus and Lactobacillus species contributing to flavor and texture
Cheese
Proteins that contain heme, a molecule that holds an iron atom in its center
Cytochromes
In prokaryotic cells undergoing respiration, protons are pumped A. from outside the cell to inside the cell. B. from the mitochondrial matrix to the intermembrane space. C. from the periplasmic space to inside the cell. D. from inside the cell to outside the cell membrane.
D. From inside the cell to outside the cell membrane
T/F: In a biochemical pathway, the product of the first reaction becomes the substrate in the second reaction.
True
T/F: protons used to test up the proton motive force as generated as macromolecules like glucose are oxidized in the cell
True
T/F: the energy captured in the phosphorylation of ADP to ATP comes from the proton votive force created in respiration
True
the set of chemical reactions that synthesize and assemble the subunits of macromolecules
anabolism
microbial breakdown of corn stalks, sugar cane, and wood into ethanol
biofuels
A culture of E. coli is growing on glucose salts agar (GSA), a chemically defined medium that contains glucose as its sole carbon source. E. coli utilizes the glucose for both its energy and carbon needs. During metabolism, it uses precursor metabolites of its central metabolic pathways and ATP to build up the biological macromolecules needed to make cell components. These biosynthetic reactions are best described as _________. A. glycolysis B. catabolism C. metabolism D. anabolism
D. Anabolism
The terminal electron acceptor in anaerobic respiration is A. Nitrate B. Water C. Pyruvic acid D. Oxygen
D. Oxygen
Who showed that crushed yeast cells could convert sugar to ethanol and CO2?
Edward Buchner
Examples of Coenzymes
FAD, NAD+, NADP+
coenzymes include ______, _______, _____
FAD, NAD+, NADP+
T/F: All biochemical pathways have the same number of enzymatic reactions.
False
T/F: An enzyme can only bind one substrate at a time.
False
T/F: an enzyme speeds up a chemical reaction in the cell, but can only be used once.
False
T/F: in prokaryotes and eukaryotes, the TCA cycle takes place in the mitochondria
False
T/F: the cytoplasmic membrane is permeable to protons
False
Proteins that are synthesized from the vitamin riboflavin
Flavoproteins
Cells prefer to use carbs as energy sources b/c they are such good donors of ________ and _______.
Hydrogen and electrons
metabolic pathways of organisms such as E. Coli
Model for eukaryotic cells
In aerobic respiration, ______ serves as the terminal electron acceptor
O2
The electron transport chain is apart of ______
Respiration
Consider the 3 key central metabolic pathways (glycolysis, pentose phosphate pathway, and TCA cycle). If you had to summarize what these pathways accomplish as they oxidize glucose, what three important items would you say they produce? a. co2 b. water c. precursor metabolites d. reducing power e. ATP
c,d,e
the set of chemicals that degrade compounds, releasing their energy
catabolism
The process that links the electron transport chain to ATP synthesis is called the _________ theory
chemiosmotic
An organic cofactor that functions as a loosely bound carrier of molecules or electrons to assist an enzyme is called a ______.
coenzyme
In prokaryotic cells, all the central metabolic pathways occur in the _________.
cytoplasm
The energy released is then used to drive anabolic reactions in the cell that are ______.
endergonic
The binding of a substrate to the active sites of an enzyme causes the shape of the flexible enzyme to change slightly. This induced fit results in a temporary intermediate called ________-__________ ___________.
enzyme-substrate complex
In terms of energy, the series of catabolic reactions by which a cell breaks down glucose are _______.
exergonic
T/F: cells growing in glucose-salts medium use glucose exclusively as an energy source
false
The energy available to do work is ______ _______.
free energy
The primary pathway used by many organisms to convert glucose to pyruvate is ________.
glycolysis
splits glucose and gradually oxidizes it to two molecules of pyruvate; generates some ATP and reducing power plus 6 precursor metabolites
glycolysis
products characteristics of specific microbes
identifying markers
cofactors include ______, ______, ______
magnesium, zinc, copper
The series of sequential chemical reactions that converts a starting compound to an end product is called a _______ _________.
metabolic pathway
the sum total of chemical reactions in a cell
metabolism
The TCA cycle completes the ______ of glucose
oxidation
Energy released in an exergonic reaction that is used to power the addition of P to ADP.
substrate-level phosphorylation
metabolic processes unique to prokaryotes
target of antimicrobial drugs