Cell Bio: Chapter 13

Nucleotide that is produced by the hydrolysis of the terminal phosphate of GTP, a reaction that also produces inorganic phosphate.

GDP (guanosine 5′-diphosphate)

Process in bacteria and mitochondria in which ATP formation is driven by the transfer of electrons from food molecules to molecular oxygen.

oxidative phosphorylation

How much ATP must be invested during the first part of glycolysis for each molecule of glucose broken down? A. 1 B. 2 C. 4

2

When fatty acids are oxidized to acetyl CoA, each cycle of the reaction removes how many carbon atoms from the fatty acid molecule? A. 1 B. 2 C. 3 D. 4

2

From one glucose molecule, how much net energy (in the form of ATP and NADH) is produced during glycolysis? A. 2 ATP, 2 NADH B. 4 ATP, 4 NADH C. 4 ATP, 2 NADH D. 2 ATP, 4 NADH

2 ATP, 2 NADH

The complete oxidation of glucose to H2O and CO2 produces about how many molecules of ATP per molecule of glucose? A. 2 B. 4 C. 12 D. 30

30

The energy released by oxidizing glucose is saved in the high-energy bonds of: A. ADP and other activated carrier molecules. B. ATP and other activated carrier molecules. C. GDP and other activated carrier molecules. D. H2O and CO2.

ATP and other activated carrier molecules.

Nucleoside triphosphate used in the synthesis of RNA and DNA. Like the closely related ATP, serves as an activated carrier in some energy-transfer reactions. Also has a special role in microtubule assembly, protein synthesis, and cell signaling.

GTP (guanosine 5′-triphosphate)

Process by which cells harvest the energy stored in food molecules; usually accompanied by the uptake of O2 and the release of CO2.

cell respiration

Intermediates formed in glycolysis and the citric acid cycle are used by the cell to synthesize: A. (A) amino acids. B. (B) nucleotides. C. (C) lipids. D. All of the above E. A and B, but not C

All of the above

Which of the following describes a breakdown process in which enzymes degrade complex molecules into simpler ones? A. Anabolism B. Catabolism

Catabolism

In plants, fats and starch are stored in which part of the cell? A. Vacuole B. Chloroplast C. Cytosol D. Endoplasmic reticulum

Chloroplast

The citric acid cycle converts the carbon atoms in acetyl CoA to which of the following? A. Pyruvate B. Citrate C. CO2 D. CH4

CO2

A high-energy electron carrier produced by reduction of FAD during the breakdown of molecules derived from food, including fatty acids and acetyl CoA.

FADH2 (reduced flavin adenine dinucleotide)

Metabolism can be tightly regulated because the substrates involved in these reactions are each recognized by a single, unique enzyme. A. True B. False

False

After a normal overnight fast, most of the acetyl CoA entering the citric acid cycle is derived from what type of molecule? A. Glucose B. Pyruvate C. Glycogen D. Fatty acids

Fatty acids

Under anaerobic conditions, which metabolic pathway regenerates the supply of NAD+ for glycolysis? A. The citric acid cycle B. The formation of acetyl CoA C. Fermentation D. The electron transport chain

Fermentation

For many anaerobic microorganisms, which metabolic pathway is the principle source of ATP? A. Glycolysis B. The citric acid cycle C. The electron transport chain

Glycolysis

In the electron transport chain, the oxygen atoms in O2 become part of which of the following molecules? A. CO2 molecules B. H2O molecules C. NADH molecules D. ATP molecules check my answer

H2O molecules

In humans and other mammals, gluconeogenesis occurs mainly in which type of cells? A. Pancreatic cells B. Liver cells C. Muscle cells D. Red blood cells

Liver cells

Where does the oxidative breakdown of food molecules occur in a eukaryotic cell? A. The cytosol B. Mitochondria C. The Golgi apparatus D. The endoplasmic reticulum

Mitochondria

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? A. NADH B. NAD+ C. H2O D. ATP E. ADP

NAD+

In eukaryotic cells, what is the final electron acceptor in the electron transport chain? A. H2O B. O2 C. CO2 D. NADH E. FADH2

O2

Which of the following is NOT required for glycolysis to occur? A. NAD+ B. ATP C. O2 D. ADP

O2

Which of the following is true? A. Sugars are converted to Acetyl CoA in the mitochondria; fats are converted to Acetyl CoA in the cytosol. B. Fats are converted to Acetyl CoA in the mitochondria; sugars are converted to Acetyl CoA in the cytosol. C. Sugars and fats are both converted to Acetyl CoA in the mitochondria. D. Sugars are converted to Acetyl CoA but fats are not.

Sugars and fats are both converted to Acetyl CoA in the mitochondria.

Which of the following locations is NOT used for the digestion of polymeric food molecules into monomeric subunits? A. Extracellular space (the lumen of intestines, for example) B. The cytosol of a cell C. Lysosomes

The cytosol of a cell

Which of the following generates the largest amount of ATP? A. Glycolysis B. The citric acid cycle C. The electron transport chain

The electron transport chain

What does it mean for a bond to be "high energy," such as between phosphate groups in ATP? A. The hydrolysis of such a bond is particularly energetically favorable. B. Such a bond is strong and difficult to break. C. The bond involves an extra electron.

The hydrolysis of such a bond is particularly energetically favorable.

What does the term gluconeogenesis refer to? A. The release of glucose from molecules such as glycogen B. The synthesis of glucose from small organic molecules such as pyruvate C. The breakdown of glucose in glycolysis

The synthesis of glucose from small organic molecules such as pyruvate

Series of reactions that generates large amounts of NADH by oxidizing acetyl groups derived from food molecules to CO2. In eukaryotic cells, this central metabolic pathway takes place in the mitochondrial matrix.

citric acid cycle

Series of enzyme-catalyzed reactions by which large biological molecules are synthesized from smaller subunits; usually requires an input of energy.

anabolic pathway

Describes a cell, organism, or metabolic process that operates in the absence of air or, more precisely, in the absence of molecular oxygen.

anaerobic

Interconnected sequence of enzymatic reactions in which the product of one reaction is the substrate of the next.

metabolic pathway

A series of membrane-embedded electron carrier molecules that facilitate the movement of electrons from a higher to a lower energy level, as in oxidative phosphorylation and photosynthesis.

electron-transport chain

Type of lipid used by living cells to store metabolic energy. Mainly composed of triacylglycerols.

fat

The breakdown of organic molecules without the involvement of molecular oxygen. This form of oxidation yields less energy than aerobic cell respiration.

fermentation

Set of enzyme-catalyzed reactions by which glucose is synthesized from small organic molecules such as pyruvate, lactate, or amino acids; in effect, the reverse of glycolysis.

gluconeogenesis

Six-carbon sugar that plays a major role in the metabolism of living cells. Stored in polymeric form as glycogen in animal cells and as starch in plant cells.

glucose

Branched polymer composed exclusively of glucose units used to store energy in animal cells. Granules of this material are especially abundant in liver and muscle cells.

glycogen

When food is plentiful, animals can store glucose as: A. glycogen. B. starch. C. acetyl CoA. D. All of the above

glycogen

Series of enzyme-catalyzed reactions in which sugars are partially degraded and their energy captured by the activated carriers ATP and NADH. (Literally, "sugar splitting.")

glycolysis

Sugars derived from food are broken down by: A. glycolysis, the citric acid cycle, and gluconeogenesis. B. gluconeogenesis, the citric acid cycle, and oxidative phosphorylation. C. glycolysis, the citric acid cycle, and oxidative phosphorylation. D. biosynthesis, fermentation, and the citric acid cycle.

glycolysis, the citric acid cycle, and oxidative phosphorylation.

Any protein with one or more covalently linked oligosaccharide chains. Includes most secreted proteins and most proteins exposed on the outer surface of the plasma membrane.

glycoprotein

General term for an enzyme that catalyzes addition of subunits to a nucleic acid polymer. DNA polymerase, for example, makes DNA, and RNA polymerase makes RNA.

polymerase

Three-carbon metabolite that is the end product of the glycolytic breakdown of glucose; provides a crucial link to the citric acid cycle and many biosynthetic pathways.

pyruvate

The end products of glycolysis are: A. pyruvate, ATP, and NADH. B. pyruvate, ATP, and NADPH. C. pyruvate, ADP, and NADH. D. citrate, ATP, and NADH. E. H2O and CO2.

pyruvate, ATP, and NADH.

Polysaccharide composed exclusively of glucose units, used as an energy store in plant cells.

starch

When nutrients are plentiful, plants can store glucose as: A. glycogen. B. starch. C. adipose. D. All of the above

starch

The synthesis of ATP in glycolysis occurs by: A. substrate-level phosphorylation. B. oxidative phosphorylation.

substrate-level phosphorylation.

The NADH generated during glycolysis feeds its high energy electrons to: A. the citric acid cycle. B. the electron transport chain. C. ADP. D. H2O.

the electron transport chain.