Chapter 7

Once they have been processed through the citric acid cycle, the acetyl-CoA molecules from a single glucose molecule produce:

2 ATP, 6 NADH, 4 CO2.

Recall that fatty acids (like palmitic acid) can yield substantially more ATP when compared with 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.

When a single pyruvate is converted to acetyl-CoA, the other products of the reaction are:

NADH and CO2.

Which one of the following represents the REDUCED forms of the two major electron carriers?

NADH and FADH2

During the action of ATP synthase, the kinetic energy of the proton gradient is transformed into potential energy.

false

Pyruvate oxidation produces a large amount of ATP.

false

In cellular respiration, oxygen:

gains electrons and is an oxidizing agent.

Fermentation takes place:

in the cytoplasm.

The space between the inner and outer membranes is ...

intermembrane space

In cellular respiration, glucose is _____ to CO2 and oxygen is _____ to water.

oxidized; reduced

During fermentation, pyruvate is:

reduced.

Which of the following is a mobile electron carrier in the electron transport chain? (Select all that apply.)

ubiquinone and cytochrome c

Which of the following molecules has the GREATEST potential energy?

ATP

During the citric acid cycle:

ATP is synthesized by substrate-level phosphorylation.

In a plant cell, all stages of cellular respiration are carried out in the cytoplasm.

False

Imagine that a eukaryotic cell carries a mutation impairing its ability to phosphorylate glucose during glycolysis. What is a likely result of this mutation?

Glucose could move out of the cell, slowing cellular respiration.

Some present-day bacteria use a system of anaerobic respiration characterized by an electron transport chain analogous to that found in aerobic organisms. Which of the following correctly characterizes the anaerobic electron transport chain?

It establishes a proton gradient between the cytoplasm and the extracellular fluid.

A researcher is comparing the amount of proteins contained in inner and outer mitochondrial membranes. What do you expect she will find?

The amount of proteins is greater in the inner membrane.

Which of the following statements is true regarding the equation C6H12O6 + 6O2 →6CO2+ 6H2O + energy?

The oxygen atoms in both CO2 and H2O are electronegative, and glucose is considered a reducing agent.

Which of the following statements is TRUE regarding triacylglycerols? :

Triacylglycerols can be used to generate acetyl-CoA.

Although cellular respiration is typically thought of as an aerobic process, glycolysis itself is actually anaerobic.

True

If an energy source such as sunlight is available, the citric acid cycle can run in reverse in some organisms.

True

Substrate Level Phosphorylation

a phosphorylated organic molecule directly transfers a phosphate group to ADP. The hydrolysis of a phosphorlyated organic molecule and the addition of a phosphate group to ADP. The hydrolysis reaction releases enough free energy to drive the synthesis of ATP

How did the earliest organisms on Earth most likely produce ATP?

by glycolysis

The MOST stable―that is, least reactive―form of carbon is:

carbon dioxide.

Phosphorylating glucose during phase 1 of glycolysis:

destabilizes the glucose molecule so that it can be broken down in phase 2.

The first phase of glycolysis requires the input of two ATP molecules. It is therefore:

endergonic

Starting with glycolysis, lactic acid and ethanol fermentation generate only two ATP molecules per glucose molecule. The remaining chemical energy from the glucose is found primarily in:

lactic acid and ethanol.

Phospholipids

major type of lipid found in cell membrane; made up of a glycerol backbone attached to a phosphate group and two fatty acids

The citric acid cycle begins when acetyl-CoA combines with _____ to form _____.

oxaloacetate; citrate

The final electron acceptor of the electron transport chain is:

oxygen

What is the FINAL electron acceptor in the electron transport chain?

oxygen

Another name for acetyl-CoA synthesis is:

pyruvate oxidation.

Cell Theory

states that all organisms are made up of cells, that the cell is the fundamental unit of life, and that cells come from preexisting cells. (there is no life without cells and cells are the smallest unit of life)

The space inside the inner membrane is...

the mitochondria matrix

Although glycolysis produces four molecules of ATP by substrate-level phosphorylation, the net gain of ATP for the cell is two molecules. This is due to the fact that glycolysis is—at first—endergonic.

true

At the end of glycolysis, the carbon molecules originally found in the starting glucose molecule are in the form of:

two pyruvate molecules.