Smartworks: chapter 13

The NADH generated during glycolysis and the citric acid cycle feeds its high-energy electrons to which of the following? Choose one: A. the citric acid cycle B. the electron transport chain C. H2O D. FAD E. ADP

B. the electron transport chain

In the electron transport chain, the oxygen atoms in O2 become part of which of the following molecules? Choose one: A. H2O B. ATP C. NADH D. glucose (C6H12O6) E. CO2

A. H2O

In what form do plant and animal cells store fat? Choose one: A. phospholipids B. triacylglycerol C. starch D. nitroglycerin E. glycogen

B. triacylglycerol

How do enzymes maximize the energy harvested from the oxidation of food molecules? Choose one: A. They allow the stepwise oxidation of food molecules, which releases energy in small amounts. B. They guarantee that each reaction involved in the oxidation of food molecules proceeds in just one direction. C. They allow oxidation reactions to take place without an input of activation energy. D. They allow a larger amount of energy to be released from food molecules such as glucose. E. They allow what would otherwise be an energetically unfavorable oxidation reaction to occur.

A. They allow the stepwise oxidation of food molecules, which releases energy in small amounts.

Where does the oxidative (oxygen-dependent) stage of the breakdown of food molecules occur in a eukaryotic cell? Choose one: A. mitochondrion B. endoplasmic reticulum C. cytosol D. Golgi apparatus

A. mitochondrion

What happens to the energy captured during glycolysis and the citric acid cycle by the activated carriers NADH and FADH2. Choose one: A. It is passed to an electron transport chain that uses it to oxidize food molecules. B. It is passed to an electron transport chain that uses it to generate a proton gradient across the inner mitochondrial membrane. C. It is used to drive biosynthetic reactions.It is passed to ADP to form ATP. D. It is passed to an electron transport chain that uses it to produce oxygen.

B. It is passed to an electron transport chain that uses it to generate a proton gradient across the inner mitochondrial membrane.

Although the citric acid cycle itself does not use O2, it requires a functioning electron transport chain (which uses O2) in order to regenerate which molecule for further use in the citric acid cycle? Choose one: A. ADP B. NAD+ C. NADH D.FADH2 E. ATP

B. NAD+

Under anaerobic conditions, which metabolic pathway regenerates the supply of NAD+ needed for glycolysis? Choose one: A. formation of acetyl CoA B. fermentation C. breakdown of fats D. breakdown of amino acids E. citric acid cycle

B. fermentation

What occurs in the first step of the citric acid cycle? Choose one: A. ATP is consumed. B. NADH is produced. C. A two-carbon molecule is combined with a four-carbon molecule to form citrate. D. Two molecules of acetyl CoA combine to form oxaloacetate. E. CO2 is released.

C. A two-carbon molecule is combined with a four-carbon molecule to form citrate.

Useful energy is obtained by cells when sugars derived from food are broken down by which processes? Choose one: A. gluconeogenesis, the citric acid cycle, and oxidative phosphorylation B. gluconeogenesis, fermentation, and oxidative phosphorylation C. glycolysis, the citric acid cycle, and oxidative phosphorylation D. glycolysis, the citric acid cycle, and gluconeogenesis E. glycolysis, the Calvin cycle, and oxidative phosphorylation

C. glycolysis, the citric acid cycle, and oxidative phosphorylation

The ethanol in wine and beer is produced from metabolic reactions carried out by the yeast Saccharomyces cerevisiae. Since it is of great commercial value, researchers have studied factors that influence ethanol production. To maximize ethanol yield, which environmental factor should be limiting? Choose one: A. glucose B. carbon dioxide C. oxygen D. sunlight

C. oxygen

Most of the energy released by oxidizing glucose is saved in the high-energy bonds of what molecules? Choose one: A. GDP and other activated carriers B. H2O and CO2 C. ADP and other activated carriers D. ATP and other activated carriers E. O2

D. ATP and other activated carriers

Which two-carbon molecule enters the citric acid cycle? Choose one: A. citrate B. oxaloacetate C. pyruvate D. acetyl CoA E. carbon dioxide

D. acetyl CoA

When food is plentiful, animals can store glucose as what? Choose one: A. acetyl CoA B. glucose 6-phosphate C. glycogen or starch D. glycogen E. starch

D. glycogen

When nutrients are plentiful, plants can store glucose as what? Choose one: A. glucose 6-phosphate B. glycogen and starch C. glycogen D. starch E. fats

D. starch

In eukaryotic cells, what is the final electron acceptor in the electron transport chain? Choose one: A. NAD+ B. ATP C. FADH2 D. CO2 E. O2

E. O2

Which of the following processes generates the largest number of ATP molecules? Choose one: A. fermentation B. citric acid cycle C. glycolysis D. gluconeogenesis E. electron transport chain

E. electron transport chain

What does the term "gluconeogenesis" refer to? Choose one: A. the breakdown of glucose during fermentation B. the breakdown of glucose during glycolysis C. the release of glucose from molecules such as glycogen D. the transport of glucose across a cell membrane E. the synthesis of glucose from small organic molecules such as pyruvate

E. the synthesis of glucose from small organic molecules such as pyruvate