Quiz 6: Cellular Respiration
Starting with one molecule of glucose, glycolysis results in the net production of which of the following sets of energy-containing products?
2 NADH, 2 pyruvate, and 2 ATP
In the absence of oxygen, suppose a single yeast cell undergoes fermentation and uses 100 molecules of glucose. How many molecules of ATP will be generated?
200
For each mole of glucose (C6H12O6) oxidized by cellular respiration, how many moles of CO2 are released in the citric acid cycle (see the accompanying figure)?
4
Predict how many molecules of carbon dioxide are produced from the mitochondrial "burning" of one molecule of glucose?
6
Chemiosmosis in mitochondria directly results in the synthesis of:
ATP
The main function of cellular respiration is to produce:
ATP
The enzyme phosphofructokinase (PFK) catalyzes a key step in glycolysis. PFK is inhibited by high levels of which of the following molecules?
ATP and citrate
During the second half of glycolysis, what occurs?
ATP is made
Which of the listed statements describes the results of the following reaction? C6H12O6+ 6 O2→ 6 CO2+ 6 H2O + Energy
C6H12O6 gets oxidized and O2 gets reduced.
A cell has enough available ATP to meet its needs for about 30 seconds. What is likely to happen when an athlete exhausts his or her ATP supply?
Catabolic processes are activated that generate more ATP.
During which stage of cellular respiration is the majority of the ATP produced?
Electron transport chain
Which stage of cellular respiration requires oxygen that you breathe?
Electron transport chain
What compound receives electrons from NADH?
FMN
Identify the stage (or stages) of cellular respiration that occurs entirely outside of the mitochondria.
Glycolysis
Which of the following statements best describes the primary role played by oxygen in cellular respiration?
It serves as the final acceptor for electrons from the electron transport chain.
Which of the following statements about NAD+is true?
NAD+ is reduced to NADH during glycolysis, pyruvate oxidation, and the citric acid cycle
Following glycolysis and the citric acid cycle, but before the electron transport chain and oxidative phosphorylation, the carbon skeleton of glucose has been broken down to CO2 with some net gain of ATP. Most of the energy from the original glucose molecule at that point in the process, however, is stored in the form of which of the following molecules?
NADH
Which electron carrier(s) function in the citric acid cycle?
NADH and FADH2
Alcohol is a waste product produced by yeast in the presence of sugar and the absence of ________.
O2
Why does yogurt taste sharp?
The taste is from the lactic acid it contains, and acids taste sharp.
What do the electrons added to NAD+ do?
They go to another pathway for ATP production.
Can energy be harvested by the cells from glucose without oxygen?
Yes, but much less than with oxygen
A reducing chemical reaction ________
adds an electron to the substrate
What is removed from pyruvate during its conversion into an acetyl group?
carbon dioxide
In chemiosmosis, what is the most direct source of energy that is used to convert ADP + Pi to ATP?
energy released from movement of protons through ATP synthase, down their electrochemical gradient
The anaerobic breakdown of glucose is called:
fermentation
From the beginning of glycolysis to the end of the Krebs cycle, what has the cell gained from the breakdown of each molecule of glucose?
four molecules of ATP, 10 of NADH, and two of FADH2
During glycolysis, two ATP molecules are "spent" in order to convert glucose to the highly reactive molecule:
fructose 1,6-bisphosphate.
A major connection for sugars in glycolysis is ________.
glucose-6-phosphate
The effect of high levels of ADP is to ________ in cellular respiration
increase the activity of specific enzymes
In human muscle cells, fermentation (by itself) produces:
lactate
Which of the following fermentation methods can occur in animal skeletal muscles?
lactic acid fermentation
Which parts of the mitochondria are directly involved in the synthesis of ATP during chemiosmosis?
matrix and inner membrane
Where are the proteins of the electron transport chain located?
mitochondrial inner membrane
When oxygen is present:
most animal cells utilize aerobic cellular respiration
Carbon dioxide (CO2) is released during which of the following stages of cellular respiration?
oxidation of pyruvate to acetyl CoA and the citric acid cycle
The control of which enzyme exerts the most control on glycolysis?
phosphofructokinase
GTP or ATP is produced during the conversion of ________.
succinyl CoA into succinate
Chemiosmosis involves ________.
the movement of hydrogen ions across a mitochondrial membrane
How many NADH molecules are produced on each turn of the citric acid cycle
three
The end product of glycolysis is:
two pyruvate molecules.
