1. Which of the following best describes the main purpose of the combined processes of glycolysis and cellular respiration?
Respuesta
breaking down ATP, so that ADP and P can be reused
transforming the energy in glucose and related molecules in a chemical form that cells can use for work
the breakdown of glucose to carbon dioxide and water
producing complex molecules from chemical building blocks
Pregunta 2
Pregunta
In the combined processes of glycolysis and cellular respiration, what is consumed and what is produced?
Respuesta
Water is consumed, and ATP is produced.
Oxygen is consumed, and glucose is produced.
Carbon dioxide is consumed, and water is produced.
Glucose is consumed, and carbon dioxide is produced.
ATP is consumed, and oxygen is produced.
Pregunta 3
Pregunta
Substrate-level phosphorylation occurs _____.
Respuesta
in glycolysis only
in both glycolysis and the citric acid cycle
during oxidative phosphorylation
in the citric acid cycle
Pregunta 4
Pregunta
The molecule that functions as the reducing agent (electron donor) in a redox or oxidation-reduction reaction _____.
Respuesta
gains electrons and loses potential energy
loses electrons and gains potential energy
loses electrons and loses potential energy
gains electrons and gains potential energy
Pregunta 5
Pregunta
When electrons move closer to a more electronegative atom, what happens? The more electronegative atom is _____.
Respuesta
oxidized, and energy is released
oxidized, and energy is consumed
reduced, and energy is released
reduced, and energy is consumed
Pregunta 6
Pregunta
Which of the following statements about NAD+ is true?
Respuesta
NAD+ has more chemical energy than NADH.
In the absence of NAD+, glycolysis can still function.
NAD+ is reduced to NADH during glycolysis, pyruvate oxidation, and the citric acid cycle.
NAD+ can donate electrons for use in oxidative phosphorylation.
Pregunta 7
Pregunta
Which of the following describes the process of glycolysis?
Respuesta
It converts one glucose molecule to two molecules of pyruvate and carbon dioxide.
It represents the first stage in the chemical oxidation of glucose by a cell.
Glycolysis occurs in the mitochondria.
Glycolysis produces 30 ATP from each molecule of glucose.
It requires ATP and NADH.
Pregunta 8
Pregunta
The free energy for the oxidation of glucose to CO2 and water is -686 kcal/mol and the free energy for the reduction of NAD+ to NADH is +53 kcal/mol. Why are only two molecules of NADH formed during glycolysis when it appears that as many as a dozen could be formed?
Respuesta
There is no CO2 or water produced as products of glycolysis.
Most of the free energy available from the oxidation of glucose is used in the production of ATP in glycolysis.
Most of the free energy available from the oxidation of glucose remains in pyruvate, one of the products of glycolysis.
Glycolysis is a very inefficient reaction, with much of the energy of glucose released as heat.
Pregunta 9
Pregunta
Starting with one molecule of glucose, the energy-containing products of glycolysis are _____.
Respuesta
2 NAD+, 2 pyruvate, and 2 ATP
2 NADH, 2 pyruvate, and 2 ATP
2 FADH2, 2 pyruvate, and 4 ATP
6 CO2, 2 pyruvate, and 2 ATP
Pregunta 10
Pregunta
Which kind of metabolic poison would most directly interfere with glycolysis?
Respuesta
an agent that closely mimics the structure of glucose but is not metabolized
an agent that reacts with NADH and oxidizes it to NAD+
an agent that binds to pyruvate and inactivates it
an agent that reacts with oxygen and depletes its concentration in the cell