pearsons review

Which of the following statements is true comparing the simple diffusion of a substance across a membrane to the facilitated/active transport of a substance across a membrane?

Simple diffusion differs from facilitated diffusion and active transport in that it is not dependent on a membrane protein, does not exhibit saturation kinetics, and is not subject to competitive inhibition.

In a human erythrocyte, a common form of membrane transport would be __________.

glucose entering the cell via facilitated diffusion

Membrane potential is __________. For a cell with a negative membrane potential, the movement of anions from outside to inside the cell is expected to be __________.

the difference in net charge on opposite sides of a membrane; more difficult

The rate of simple diffusion of a polar molecule across a membrane is directly and linearly proportional to __________. The thickness of a membrane is expected to be __________ to the rate of simple diffusion for polar molecules.

its concentration difference across the membrane; inversely proportional

The Na⁺–glucose symporter serves to move one molecule of glucose into the cell and 2 Na⁺ into the cell despite the concentration of glucose being almost equal inside the cell and outside the cell. Which of the following must be true?

The facilitated diffusion of Na⁺ down its electrochemical gradient provides the energy to transport glucose against its concentration gradient.

Which of the following compounds would NOT alter the behavior of a plasma membrane voltage-gated channel?

a drug that inhibits GLUT1 (the glucose transporter)

Which of the following is NOT a type of transport ATPase?

S-type

Cystic fibrosis is caused by a defective __________.

chloride ion channel

Halobacteria express bacteriorhodopsin, a transmembrane protein that uses light energy to __________.

create a proton gradient

The K_eq for transport of an uncharged solute moving into a cell by diffusion is __________.

less than 1

A person who is deficient in niacin would not be able to maintain glycolysis. This is because niacin is used to make __________. This molecule serves as a(n)__________ in metabolism.

NAD⁺; coenzyme

Anabolic pathways __________.

involve biosynthesis

Which of the following is NOT an example of a biological oxidation?

the conversion of glyceraldehyde-3-phosphate to 1,3-bisphosphoglycerate

Which of the following statements is true of fructose-2,6-bisphosphate (F2,6BP)?

All of the other answers are true.

Which of the following statements is NOT true of glycolysis?

It oxidizes glucose to form carbon dioxide.

The glycolytic enzymes that are allosterically regulated are __________.

enzymes that catalyze reactions with large negative ΔG's

The indirect regulation of phosphofructokinase-2 (PFK-2) that is mediated by the hormones glucagon and epinephrine __________.

influences the Cori cycle

In comparing glycolysis and gluconeogenesis, it can be said that __________.

only gluconeogenesis has a four-carbon intermediate

Which two enzymes of glycolysis generate phosphorylated compounds that have enough energy of hydrolysis to synthesize ATP?

phosphoglycerate kinase and pyruvate kinase

Which of these is NOT a key regulatory enzyme in glycolysis?

pyruvate carboxylase

In aerobic cellular respiration, __________ is oxidized and __________ is reduced.

pyruvate; oxygen

Which of the following explains why multiple electron transport complexes are used to oxidize NADH rather than allowing NADH to reduce O₂ in a single step?

The oxidation of NADH to reduce O₂ in a single step would release an enormous amount of energy at once, most of which would likely be lost as heat. A single step oxidation would be extremely complicated.

During the oxidative decarboxylation step, Coenzyme A serves to __________ carbon atoms of pyruvate for reaction.

activate

Which of the following is NOT a function of the TCA cycle?

All of the other answer choices are functions of the TCA cycle.

Rank the following partial list of electron carriers in the electron transport system in order from lowest to highest standard reduction potentials: cytochrome a3, cytochrome c1, cytochrome c, FMN, coenzyme Q, and cytochrome b.

FMN, coenzyme Q, cytochrome b, cytochrome c1, cytochrome c, and cytochrome a3

Cyanide blocks the electron transport system by __________.

binding to cytochrome c oxidase

Which of the following accurately represents the series of chemical transformations necessary for plants to convert fats into an intermediate of glycolysis to make glucose via the glyoxylate cycle?

acetyl CoA, succinate, malate, oxaloacetate, and then phosphoenolpyruvate

In bacteria, the TCA cycle takes place in the __________.

cytoplasm

Organisms that use ferric ions and elemental sulfur as terminal electron acceptors of their electron transport systems are undergoing __________.

anaerobic respiration

A TCA cycle enzyme that was allosterically regulated could be expected to be __________.

activated by ADP and inhibited by NADH

The energy transduction reactions of photosynthesis generate high-energy electrons, which ultimately end up in __________. In addition to oxygen, these reactions also produce __________.

NADPH; ATP

Which of the following is a chemically accurate description of the chemical strategy employed by photosystem II?

Photosystem II absorbs a photon, causing the reduction potential of P680 to become more negative and make a very powerful reducing agent.

Most of the pigments, enzymes, and carriers involved in photosynthetic electron transport are associated with the thylakoid membrane. Protons are pumped into the __________, creating a proton gradient to drive chemiosmotic ATP synthesis, and the __________ is where the Calvin cycle occurs.

thylakoid lumen; stroma

The plasma membrane of cyanobacteria folds into a structure that closely resembles __________.

thylakoids

Carotenoids and phycobilins are __________. The function of these molecules is to __________.

accessory pigments; absorb photons that chlorophyll cannot

Which of the following statements is true of rubisco?

All of the other answers are correct.

When a plant cell requires a high demand of ATP, which of the following will likely dominate in the chloroplast?

cyclic electron transport

Unlike C₃ and C₄ plants, CAM plants __________.

open their stomata during the night

Which of the following statements is true of cyclic photophosphorylation?

All of the answers are true.

The enzyme PEP carboxylase __________.

can trap CO₂ even at relatively low CO₂ concentrations