Biology Chapter 7 Part 1 (Homework)
Oxidative phosphorylation yields _____ ATP for each molecule of FADH2 that is oxidized, whereas it yields _____ ATP for each molecule of NADH.
1.5; 2.5 (dividing 5 by 2 for NADH and 3 divided by 3 for FADH2)
The ethanol resulting from fermentation of glucose only accounts for four of the six starting carbon atoms. In which of the following are the other two carbon atoms found?
?
Energy released by transferring electrons along the electron transport chain is stored as potential energy in the form of:
a proton gradient.
During glycolysis, pyruvate oxidation, and the citric acid cycle, the chemical energy in glucose is transferred to:
electron carriers and ATP.
The majority of the energy captured in the citric acid cycle is in the form of:
electrons donated to NAD+ and FAD.
Based on your interpretation of this model of phosphofructokinase-1 (PFK-1) activity, which of the following would decrease PFK-1 activity?
increased concentration of citrate (refer to figure 7.20)
In eukaryotes, pyruvate oxidation takes place in the
mitochondrial matrix
The citric acid cycle takes place in the:
mitochondrial matrix.
In what organelle is pyruvate oxidation carried out in a cell?
mitochondrion
Which stages of cellular respiration use O2 as an input?
oxidative phosphorylation
The final (terminal) electron acceptor of the electron transport chain is
oxygen
Which stages of cellular respiration produce CO2 as a waste product?
pyruvate oxidation and the citric acid cycle
When you exhale, there is more CO2 than was present in the air that you inhaled. This CO2 comes from reactions in:
pyruvate oxidation and the citric acid cycle.
In pyruvate oxidation, the electron donor is _____ and the electron acceptor is _____.
pyruvate; NAD+ (refer to figure 7.3)
During lactic acid fermentation, pyruvate is:
reduced. (refer to figure 7.14)
We can tell from their structure that fatty acids are a good source of energy because of:
the large number of carbon-carbon and carbon-hydrogen bonds they contain.
In addition to destabilizing glucose for subsequent breakdown, what else does phosphorylation of glucose do?
traps glucose inside the cell
Cellular respiration is a series of _____ reactions.
catabolic
Tracing the metabolism of one glucose molecule, how many carbon atoms are fully oxidized to CO2 at the completion of glycolysis?
0
Starting from glucose, lactic acid fermentation results in _____ molecules of lactic acid, each with _____ carbons, whereas ethanol fermentation results in _____ molecules of ethanol, each with _____ carbons.
2; 3; 2; 2 (refer to figure 7.14)
During the citric acid cycle
ATP is synthesized by substrate level phosphorylation.
During the pyruvate oxidation stage of cellular respiration, which of the following occurs?
All of these choices are correct, the formation of CO2 the formation of NADH the oxidation of pyruvate the formation of acetyl-CoA
Each molecule of acetyl-CoA that enters the citric acid cycle carries two of the carbon atoms from the original starting glucose molecule. These carbon atoms will ultimately leave the citric acid cycle as carbon atoms in which of the following?
CO2
Recall that fatty acids (such as palmitic acid) can yield substantially more ATP when compared with a similar weight of glucose. Why doesn't aerobic respiration rely solely on fatty acids as energy sources, rather than glucose?
Fatty acids cannot be used by some vital tissues in the human body, such as the brain.
What happens when glucose is phosphorylated during phase 1 of glycolysis?
Glucose is destabilized so that it can be broken apart in phase 2.
Which of the following is one explanation for why glycolysis is believed to have arisen very early in the evolution of life?
It does not require oxygen.
What product of the pyruvate oxidation stage of cellular respiration will have the two electrons that are lost from pyruvate?
NADH
When a single pyruvate is converted to acetyl-CoA during pyruvate oxidation, the other products of the reaction are:
NADH and CO2.
A researcher is comparing the amount of protein contained in inner and outer mitochondrial membranes. What do you predict they will find?
The amount of proteins will be greater in the inner membrane.
Oxidation
The loss of electrons.
Glycolysis is
anaerobic
Lactic acid fermentation occurs in
animals and bacteria
Excess glucose is stored in large branched molecules of:
glycogen in animals/ starch in plants
Due to the pumping action of the electron transport chain, protons have a high concentration in the _____ and a low concentration in the _____.
intermembrane space; mitochondrial matrix
Red blood cells in the human bloodstream do not have mitochondria. What metabolic process would you predict these cells use to provide cellular energy/ATP?
lactic acid fermentation
The ATP produced during glycolysis is the result of substrate-level phosphorylation.
true