Biology Exam 2 Practice Test

Green olives may be preserved in brine, which is a 30% salt solution. How does this method of preservation prevent microorganisms from growing in the olives? a) A 30% salt solution is hypertonic to the bacteria, so they lose too much water and plasmolyze. b) A 30% salt solution is hypotonic to the bacteria, so they gain too much water and burst. c) High salt concentration lowers the pH, thus inhibiting bacterial metabolism. d) Bacterial cells shrivel up in high salt solutions, causing the cell to burst. e) High salt concentration raises the pH, thus inhibiting bacterial metabolism.

a 30% salt solution is hypertonic to the bacteria, so they lose too much water and plasmolyze

In addition to the fundamental structures required to be defined as a cell, a particular cell also has a nucleus and chloroplasts. Based on this information, this cell could be _____. a) a yeast (fungus) cell b) a cell from the intestinal lining of a cow c) a bacterium d) a protistal cell or a plant cell

a protistal cell or plant cell

Which of the following is a correct difference between active transport and facilitated diffusion? a) Active transport involves transport proteins, and facilitated diffusion does not. b) Facilitated diffusion involves transport proteins, and active transport does not. c) Active transport requires energy from ATP, and facilitated diffusion does not. d) Active transport can move solutes in either direction across a membrane, but facilitated diffusion can only move in one direction. e) Facilitated diffusion can move solutes against a concentration gradient, and active transport cannot.

active transport requires energy from ATP, and facilitated diffusion does not

The use of non-C3 and non-CAM plants as crops may be limited in some regions because on hot, dry days, they close their stomata. What happens as a result of closing their stomata? a) It reduces water loss. b) It prevents carbon dioxide from entering the leaf. c) In a process called photorespiration, rubisco binds oxygen instead of carbon dioxide. d) It builds up oxygen from the light reactions in the leaf. e) All of the listed responses are correct.

all the listed responses are correct

Which of the following statements about enzymes is incorrect? a) An enzyme is consumed during the reaction it catalyzes. b) An enzyme is very specific in terms of which substrate it binds to. c) Most enzymes are proteins. d) An enzyme lowers the activation energy of a chemical reaction. e) Enzymes can be used to accelerate both anabolic and catabolic reactions.

an enzyme is consumed during the reaction it catalyzes

Which of the following correctly states the relationship between anabolic and catabolic pathways? a) Energy derived from catabolic pathways is used to drive the breakdown of organic molecules in anabolic pathways. b) Catabolic pathways produce usable cellular energy by synthesizing more complex organic molecules. c) The flow of energy between catabolic and anabolic pathways is reversible. d) Degradation of organic molecules by anabolic pathways provides the energy to drive catabolic pathways. e) Anabolic pathways synthesize more complex organic molecules using the energy derived from catabolic pathways.

anabolic pathways synthesize more complex organic molecules using the energy derived from catabolic pathways

What is the range of wavelengths of light that are absorbed by the pigments in the thylakoid membranes? a) green, which is why plants are green b) blue-violet and red-orange c) the entire spectrum of white light d) the infrared e) the range absorbed by carotenoids only

blue-violet and red-orange

In photosynthesis, plants use carbon from _____ to make sugar and other organic molecules. a) water b) carbon dioxide c) chlorophyll d) the sun

carbon dioxide

Which of the following molecules is most likely to passively diffuse across the plasma membrane? a) carbon dioxide b) hemoglobin c) sodium ion d) glucose e) DNA

carbon dioxide

Which of the following structures is found in animal cells but NOT plant cells? a) Golgi apparatus b) centrioles c) plasma membrane d) mitochondria e) rough endoplasmic reticulum

centriols

Which of the following statements about chloroplasts and mitochondria is true? a) Chloroplasts and mitochondria are components of the endomembrane system. b) Chloroplasts and mitochondria have three sets of membranes. c) Chloroplasts and mitochondria synthesize some of their own proteins. d) Mitochondria but not chloroplasts contain a small amount of DNA. e) Chloroplasts but not mitochondria are completely independent of the cell of which they are a part.

chloroplasts and mitochondria synthesize some of their own proteins

Which of the following functional processes is not a consequence of the association of proteins with biological membranes? a) intercellular joining b) enzymatic activity c) cell-cell recognition d) cell-cell communication e) energy, carbon, and nitrogen storage

energy, carbon, nitrogen storage

The function of cellular respiration is to _____. a) reduce CO2 b) extract CO2 from the atmosphere c) extract usable energy from glucose d) produce carbohydrates e) synthesize macromolecules from monomers

extract usable energy from glucose

Which of the following statements about diffusion is true? a) It requires expenditure of energy by the cell. b) It is a passive process. c) It occurs when molecules move from a region of lower concentration to a region of higher concentration. d) It always requires integral proteins of the cell membrane. e) It is very rapid over long distances.

it is a passive process

A molecule becomes more oxidized when it _____. a) gains an electron b) loses an electron c) changes shape d) loses a hydrogen (H+) ion e) gains a hydrogen (H+) ion

loses an electron

Which of the following categories best describes the function of the rough endoplasmic reticulum? a) breakdown of complex foods b) energy processing c) information storage d) manufacturing e) structural support of cells

manufacturing

Which of the following structures is found in eukaryotic but not prokaryotic cells? a) plasma membrane b) mitochondria c) cytosol d) ribosomes e) DNA

mitochondria

Which type of cell is most likely to have the most mitochondria? a) bacterial cells that are growing on sugars b) inactive yeast cells that are stored for future use c) photosynthetic cells in the leaves of a tree d) muscle cells in the legs of a marathon runner e) nondividing cells in the skin on your finger

muscle cells in the legs of a marathon runner

Which of the following environments or actions would not affect the rate of an enzyme reaction? a) substrate concentration b) heating the enzyme c) cooling the enzyme d) pH e) None of the listed responses is correct.

none of the listed responses is correct

Organisms are described as thermodynamically open systems. Which of the following statements is consistent with this description? a) Organisms acquire energy from, and lose energy to, their surroundings. b) The metabolism of an organism is isolated from its surroundings. c) Heat produced by the organism is conserved in the organism and not lost to the environment. d) Because energy must be conserved, organisms constantly recycle energy and thus need no input of energy. e) All of the listed responses are correct.

organisms acquire energy from, and lose energy to, their surroundings

Most of the ATP produced in cellular respiration comes from which of the following processes? a) oxidative phosphorylation b) glycolysis c) the citric acid cycle d) reduction of NADH e) substrate-level phosphorylation

oxidative phosphorylation

Which of the following statements about passive transport is correct? a) Passive transport permits the solute to move in either direction, but the net movement of the population of solute occurs down the concentration gradient of the molecule. b) In passive transport, solute movement stops when the solute concentration is the same on both sides of the membrane. c) Passive transport does not occur in the human body. d) Passive transport operates independently of diffusion. e) Passive transport operates independently of the concentrations of the moving solute.

passive transport permits the solute to move in either direction, but the net movement of the population of solute occurs down the concentration gradient of the molecule

Which of the following pairs correctly matches a membrane transport process to its primary function? a) osmosis ... passive diffusion of water and small solutes across a membrane b) pinocytosis ... the uptake of water and small solutes into the cell by formation of vesicles at the plasma membrane c) phagocytosis ... secretion of large particles from the cell by fusion of vesicles with the plasma membrane d) None of the above is correct.

pinocytosis... secretion of large particles from the cell by fusion of vesicles

Dye injected into a plant cell might be able to enter an adjacent cell through _____. a) plasmodesmata b) a microtubule c) a cell wall

plasmodesmata

The energy given up by electrons as they move through the electron transport chain is used in which of the following processes? a) pumping H+ across a membrane b) the oxidation of water c) the production of CO2 d) the production of NADH and FADH2 e) the breakdown of glucose

pumping H+ across a membrane

Which of the following enables a cell to pick up and concentrate a specific kind of molecule? a) facilitated diffusion b) osmosis c) passive transport d) receptor-mediated endocytosis e) channel proteins

receptor-mediated endocytosis

Muscle tissues make lactate from pyruvate to do which of the following? a) get rid of pyruvate produced by glycolysis b) speed up the rate of glycolysis c) produce additional CO2 d) utilize the energy in pyruvate e) regenerate NAD+

regenerate NAD+

Which of the following accompanies the conversion of pyruvate to acetyl CoA before the citric acid cycle? a) formation of CO2 and synthesis of ATP b) release of CO2 and synthesis of NADH c) removal of coenzyme A d) regeneration of NAD+ e) release of CO2 and release of coenzyme A

release of CO2 and synthesis of NADH

An exergonic (spontaneous) reaction is a chemical reaction that _____. a) occurs only when an enzyme or other catalyst is present b) leads to a decrease in the entropy of the universe c) cannot occur outside of a living cell d) is common in anabolic pathways e) releases energy when proceeding in the forward direction

releases energy when proceeding in the forward direction

Which of the following groups is primarily involved in synthesizing molecules needed by the cell? a) vacuole, rough endoplasmic reticulum, smooth endoplasmic reticulum b) lysosome, vacuole, ribosome c) ribosome, rough endoplasmic reticulum, smooth endoplasmic reticulum d) rough endoplasmic reticulum, lysosome, vacuole e) smooth endoplasmic reticulum, ribosome, vacuole

ribosome, rough ER and smooth ER

The Calvin cycle occurs in the _____. a) thylakoid membrane b) thylakoid lumen c) stroma d) stomata e) matrix

stomata

Which of these statements about enzyme inhibitors is true? a) A noncompetitive inhibitor does not change the shape of the active site. b) The action of competitive inhibitors may be reversible or irreversible. c) When the product of an enzyme or an enzyme sequence acts as its inhibitor, this is known as positive feedback. d) Inhibition of enzyme function by compounds that are not substrates is something that only occurs under controlled conditions in the laboratory. e) A competitive inhibitor binds to the enzyme at a place that is separate from the active site.

the action of competitive inhibitors may be reversible or irreversible

Which of the following is changed by the presence of an enzyme in a reaction? a) the activation energy b) The sign of ΔG c) the G value for the products d) the magnitude of ΔG. e) the G value for the reactants

the activation energy

Which of the following is an example of the second law of thermodynamics as it applies to biological reactions? a) The aerobic respiration of one molecule of glucose produces six molecules each of carbon dioxide and water. b) All types of cellular respiration produce ATP. c) Cellular respiration releases some energy as heat. d) The first and second choices are correct. e) The first, second, and third choices are correct.

the aerobic respiration of one molecule of glucose produces six molecules each of carbon dioxide and water

Most of the NADH that delivers electrons to the electron transport chain comes from which of the following processes? a) the citric acid cycle b) glycolysis c) substrate-level phosphorylation d) anabolic pathways e) oxidative phosphorylation

the citric acid cycle

What is meant by the "induced fit" of an enzyme? a) The presence of the substrate in solution induces the enzyme to slightly change its structure. b) The shape of the active site is nearly perfect for specifically binding the enzyme's substrate(s) c) The substrate can be altered so that it is induced to fit into the enzyme's active site. d) The enzyme structure is altered so that it can be induced to fit many different types of substrate. e) The enzyme changes its shape slightly as the substrate binds to it.

the enzyme changes its shape slightly as the substrate binds to it

Rubisco is _____. a) the enzyme in plants that first captures CO2 to begin the Calvin cycle b) the enzyme responsible for splitting H2O to produce O2 in photosynthesis c) the enzyme that forms a 4-carbon compound in CAM photosynthesis d) the first stable intermediate in C4 photosynthesis e) the 5-carbon sugar molecule that reacts with CO2 to begin the Calvin cycle

the enzyme in plants that first captures CO2 to begin the Calvin cycle

From the equation ΔG = ΔH - TΔS it is clear that _____. a) a decrease in the system's total energy will increase the probability of spontaneous change b) increasing the entropy of a system will increase the probability of spontaneous change c) increasing the temperature of a system will increase the probability of spontaneous change d) The first and second choices are correct. e) The first three choices are correct.

the first three choices are correct

The ATP synthase in a human cell obtains energy for synthesizing ATP directly from which of the following processes? a) the movement of electrons through a series of carriers b) the flow of H+ across the inner mitochondrial membrane through the ATP synthase enzyme c) the oxidation of NADH and FADH2 d) the oxidation of glucose e) the reduction of oxygen

the flow of H+ across the inner mitochondrial membrane through the ATP synthase enzyme

Why is the citric acid cycle called a cycle? a) The acetyl CoA that enters the cycle is regenerated in the last step of the pathway. b) NAD+ and FAD are recycled. c) All of the carbon from glucose is cycled back into the atmosphere as carbon dioxide. d) NADH is cycled down the electron transport chain. e) The four-carbon acid that accepts the acetyl CoA in the first step of the cycle is regenerated by the last step of the cycle.

the four-carbon acid that accepts the acetyl CoA in the first step of the cycle is regenerated by the last step of the cycle

What best characterizes the role of ATP in cellular metabolism? a) The ΔG associated with its hydrolysis is positive. b) It is catabolized to carbon dioxide and water. c) The free energy released by ATP hydrolysis may be coupled to an endergonic process via the formation of a phosphorylated intermediate. d) The charge on the phosphate group of ATP tends to make the molecule very watersoluble. e) The release of free energy during the hydrolysis of ATP heats the surrounding environment.

the free energy released by ATP hydrolysis may be coupled to an endergonic process via the formation of a phosphorylated intermediate

Which of the following statements correctly describes the relationship between the light reactions and the Calvin cycle? a) The light reactions produce carbon dioxide, ATP, NADPH, all of which are used in the Calvin cycle. b) The light reactions produce ATP and NADPH, both of which are used in the Calvin cycle. c) The light reactions produce ADP and NADP+, both of which are used in the Calvin cycle. d) The light reactions produce water, ATP, NADPH, all of which are used in the Calvin cycle. e) The light reactions produce carbon dioxide and water, all of which are used in the Calvin cycle.

the light reactions produce ATP and NADPH, both of which are used in the Calvin cycle

In the citric acid cycle, for each pyruvate that enters the cycle, one ATP, three NADH, and one FADH2 are produced. For each glucose molecule that enters glycolysis, how many ATP, NADH, and FADH2 are produced in the citric acid cycle? a) four ATP, six NADH, two FADH2 b) three ATP, three NADH, one FADH2 c) one ATP, three NADH, one FADH2 d) two ATP, six NADH, two FADH2 e) about 38 ATP

two ATP, six NADH, two FADH2

Both mitochondria and chloroplasts _____. a) use chemiosmosis to produce ATP b) obtain electrons from water c) reduce NAD+, forming NADP d) release oxygen as a by-product e) are surrounded by a single membrane

use chemiosmosis to produce ATP

The source of the oxygen produced by photosynthesis has been identified through experiments using radioactive tracers. The oxygen comes from _____. a) carbon dioxide b) glucose c) radioisotopes d) water e) light

water

Where do the electrons entering photosystem II come from? a) chlorophyll molecules in the antenna complex b) ATP c) the electron transport chain d) light e) water

water

A single plant cell is placed in an isotonic solution. Salt is then added to the solution. Which of the following would occur as a result of the salt addition? a) Water would leave the cell by osmosis, causing the volume of the cytoplasm to decrease. b) There would be no osmotic movement of water in response to the added salt. c) Water would enter the cell by osmosis, and the cell would swell. d) The added salt makes the solution hypotonic compared to the cell. Water will enter the cell by osmosis.

water would leave the cell by osmosis, causing the volume of the cytoplasm to decrease