BIO 208 Ch. 8
What enzyme is used to synthesize ATP? -ATP hydrolase -ATP kinase -ATP phosphorylase -None of the choices are correct
None of the choices are correct
The electron transport chain in bacteria is located
in the cell membrane
The protons are generated during oxidation reactions.
true
The last carrier protein in the electron transport chain transfers
two electrons to oxygen
Select all of the phrases below that represent the structure and function of enzymes
-Composed of protein -Increase the rate of chemical reactions -Are used up in chemical reactions -High concentrations are necessary for activity -Activity is affected by temperature and pH -Become incorporated into the reaction product -Have active sites with which substrates interact
Select each of the statements that describe the Krebs cycle
-Most of the ATP generated during aerobic respiration of glucose is generated during the Krebs cycle -There are ten steps, each catalyzed by a different enzyme
What is the total ATP yield per glucose in organisms that carry out fermentation?
2
Select all of the products of glycolysis to test your understanding of this process
2 NADPH; Citric acid; CO2
How much ATP is generated in the electron transport system?
30
What two main types of by-products are produced in fermentation?
Alcohol; acids
Which of the following correctly represents the mechanism of enzyme function, where S is "substrate" and E is "enzyme" and P is "product"?
E + S -> E-S -> E-P -> E + P
Only yeast are able to carry out fermentation for catabolism.
False
Select the electron carriers used by cells
Glucose; ATP
Select the statement that accurately reflects fermentation
It results in the incomplete oxidation of glucose
In other microbes, the process of respiration continues when pyruvate is utilized in a set of reactions called the _____.
Krebs cycle
Which of the following best describes the reduction of the coenzyme NAD?
NAD+ + H -> NADH
What is oxidized at the beginning of the electron transport system?
NADH and FADH2
NADH serves as an electron carrier that can donate its hydrogen to other molecules.
True
Whenever a molecule is oxidized, another molecule must be reduced
True
The electron carrier proteins in the electron transport chain shuttle electrons to
a terminal acceptor
38 ATP/molecule of glucose
aerobic respiration
The electron transport chain is part of ___.
aerobic respiration
Although both aerobic respiration and anaerobic respiration utilize glycolysis, the Krebs cycle, and an electron transport system, ______ respiration uses O2 as the final electron acceptor at the end of the electron transport system, whereas ______ respiration uses an inorganic molecule other than O2 as the final electron acceptor.
aerobic; anaerobic
Cell that conduct ______ respiration utilize free oxygen as a final electron acceptor in this process, while those that conduct _______ respiration use oxygen-containing ions to create ATP molecules
aerobic; anaerobic
2-36 ATP/molecule of glucose
anaerobic respiration
The NADH involved in the electron transport chain is made
by redox reactions in glycolysis and the Krebs cycle
What is a by-products of the Krebs cycle?
carbon dioxide
The Krebs cycle produces a small amount of ATP, but also generates the reduced _____ NADH and FADH2.
carriers
Synthesis of ATP via a proton gradient is called ______.
chemiosmosis
Where does the Krebs cycle take place in bacteria?
cytoplasm
Glycolysis occurs in the _____ and overall generates ___ ATP.
cytoplasm; 2
Where do NADH and FADH2 go after being produced in the Krebs cycle?
electron transport chain
These molecules then bring _____ generated by glycolysis and the Krebs cycle to the ________ embedded in the bacterial cell _____.
electrons; electron transport system; membrane
In bacteria and eukaryotes, the Krebs cycle takes place in the mitochondria.
false
The Krebs cycle is part of fermentation, as well as cellular respiration.
false
The membrane is permeable to protons
false
2 ATP/molecule
fermentation
During glycolysis, ___ is oxidized and ____ is reduced.
glucose; NAD+
The processes of aerobic and anaerobic respiration, as well as fermentation, all begin with ____.
glycolysis
In bacteria, the electron transport chain is located
in the plasma membrane
Glycolysis starts with ____ and ends with ____.
one glucose; two pyruvate molecules
Cells obtain energy by ________ food molecules such as glucose.
oxidizing
During aerobic respiration, the last carrier protein transfers a pair of electrons to ______.
oxygen
What is reduced at the end of the electron transport system?
oxygen
The main purpose of cellular respiration is to ____.
produce energy
In this reaction, ATP synthase uses energy from ____ to make ATP.
protons re-entering the cell
What serves as an electron acceptor in fermentation?
pyruvate or other organic molecule
The two molecules of _____ produced in glycolysis can be turned into acids and other products through _____.
pyruvate; fermentation
What is the main purpose for fermentation reactions?
regenerate NAD molecules for glycolysis
During the electron transport chain in bacteria, protons are
shuttled to the outside of the cell membrane
Which of the following binds to the active site of an enzyme?
substrate
How is anaerobic respiration different from aerobic respiration?
the final electron acceptor
Coenzyme Q
transfers protons from inside the membrane to outside the membrane
Electrons enter the electron transport chain when NADH transfers them there along with protons in the form of hydrogen.
true
The function of the enzyme ATP synthase is to
utilize the energy of the proton motive force to convert ADP to ATP.