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Introduction, Chemistry, Water

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Introduction, Chemistry, Water
 

Multiple Choice
Identify the choice that best completes the statement or answers the question.
 1.
What is a localized group of organisms that belong to the same species?
a.
 biosystem
b.
 community
c.
 population
d.
 ecosystem
e.
 organ system
 2.
Plants convert the energy of sunlight into
a.
 the energy of motion.
b.
 carbon dioxide and water.
c.
 the potential energy of chemical bonds.
d.
 minerals.
e.
 kinetic energy.
 3.
As a result of photosynthesis, plants release ____ into the atmosphere.
a.
 methane
b.
 carbon dioxide
c.
 water
d.
 minerals
e.
 oxygen
 4.
Which of the following is the main source of energy for producers such as plants and other photosynthetic organisms?
a.
 sunlight or solar energy
b.
 carbon dioxide or kinetic energy
c.
 heat or thermal energy
d.
 chemicals or chemical energy
e.
 both B and D
 5.
The dynamics of any ecosystem include the following major processes:
a.
 the flow of energy from sunlight to producers
b.
 the flow of energy from sunlight to producers and then to consumers
c.
 the recycling of chemical nutrients
d.
 the flow of energy to producers and the recycling of nutrients
e.
 the flow of energy from sunlight to producers and then to consumers, and the recycling of chemical nutrients
 6.
What are the basic “building blocks” of deoxyribonucleic acid (DNA)?
a.
 100,000 different kinds of proteins
b.
 26 different kinds of chromosomes
c.
 20 different kinds of amino acids
d.
 4 different kinds of nucleotides
e.
 3 different kinds of genomes
 7.
Which of the following is reflective of the phrase “the whole is greater than the sum of its parts”?
a.
 high-throughput technology
b.
 emergent properties
c.
 natural selection
d.
 reductionism
e.
 feedback regulations
 8.
Prokaryotic and eukaryotic cells generally have which of the following features in common?
a.
 a membrane-bounded nucleus
b.
 a cell wall made of cellulose
c.
 ribosomes
d.
 flagella or cilia that contain microtubules
e.
 linear chromosomes made of DNA and protein
 9.
Which of the following are characteristics shared by members of both domain Bacteria and domain Archaea?
a.
 cytosol
b.
 nucleus
c.
 DNA
d.
 A and C only
e.
 A, B, and C
 10.
A water sample from a hot thermal vent contained a single-celled organism that lacked a nucleus. What is its most likely classification?
a.
 domain Eukarya
b.
 domain Archaea
c.
 kingdom Animalia
d.
 kingdom Protista
e.
 kingdom Fungi
 11.
In a hypothetical world, every 50 years people over 6 feet tall are eliminated from the population. Based on your knowledge of natural selection, you would predict that the average height of the human population will
a.
 remain unchanged.
b.
 gradually decline.
c.
 rapidly decline.
d.
 gradually increase.
e.
 rapidly increase.
 12.
The method of scientific inquiry that describes natural structures and processes as accurately as possible through careful observation and the analysis of data is known as
a.
 hypothesis-based science.
b.
 discovery science.
c.
 experimental science.
d.
 quantitative science.
e.
 qualitative science.
 13.
What is a hypothesis?
a.
 the same thing as an unproven theory
b.
 a tentative explanation that can be tested and is falsifiable
c.
 a verifiable observation sensed directly, or sensed indirectly with the aid of scientific instrumentation
d.
 a fact based on qualitative data that is testable
e.
 a fact based on quantitative data that is falsifiable
 14.
The statement “If you show your dog affection, then your dog will seek your company” is an example of
a.
 a statement that can be tested.
b.
 a statement derived from a hypothesis.
c.
 a prediction.
d.
 deductive reasoning.
e.
 all of the above
 15.
Trace elements are those required by an organism in only minute quantities. Which of the following is a trace element that is required by humans and other vertebrates?
a.
 nitrogen
b.
 calcium
c.
 iodine
d.
 sodium
e.
 phosphorus
 16.
Which of the following statements is false?
a.
 Atoms of the various elements differ in their number of subatomic particles.
b.
 All atoms of a particular element have the same number of protons in their nuclei.
c.
 The neutrons and protons present in the nucleus of an atom are almost identical in mass; each has a mass of about 1 dalton.
d.
 An atom is the smallest unit of an element that still retains the properties of the element.
e.
 Protons and electrons are electrically charged particles. Protons have one unit of negative charge, and electrons have one unit of positive charge.
 17.
Each element is unique and different from other elements because of the number of protons in the nuclei of its atoms. Which of the following indicates the number of protons in an atom’s nucleus?
a.
 atomic mass
b.
 atomic weight
c.
 atomic number
d.
 mass weight
e.
 mass number
 18.
The mass number of an element can be easily approximated by adding together the number of ____ in an atom of that element.
a.
 protons and neutrons
b.
 energy levels
c.
 protons and electrons
d.
 neutrons and electrons
e.
 isotopes
 19.
The nucleus of a nitrogen atom contains 7 neutrons and 7 protons. Which of the following is a correct statement concerning nitrogen?
a.
 The nitrogen atom has a mass number of approximately 7 daltons and an atomic mass of 14.
b.
 The nitrogen atom has a mass number of approximately 14 daltons and an atomic mass of 7.
c.
 The nitrogen atom has a mass number of 14 and an atomic mass of 7 grams.
d.
 The nitrogen atom has a mass number of 7 grams and an atomic number of 14.
e.
 The nitrogen atom has a mass number of 14 and an atomic mass of approximately 14 daltons.
 20.
An atom with an atomic number of 9 and a mass number of 19 would have an atomic mass of approximately
a.
 9 daltons.
b.
 9 grams.
c.
 10 daltons.
d.
 20 grams.
e.
 19 daltons.
 21.
Two isotopes of the same element will have different numbers of
a.
 protons.
b.
 neutrons.
c.
 electrons.
d.
 protons and neutrons.
e.
 neutrons and electrons.
 22.
Electrons exist only at fixed levels of potential energy. However, if an atom absorbs sufficient energy, a possible result is that
a.
 an electron may move to an electron shell farther out from the nucleus.
b.
 an electron may move to an electron shell closer to the nucleus.
c.
 the atom may become a radioactive isotope.
d.
 the atom would become a positively charged ion, or cation.
e.
 the atom would become a negatively charged ion, or anion.
 23.
The atomic number of neon is 10. Therefore, which of the following is correct about an atom of neon?
a.
 It has 8 electrons in its outer electron shell.
b.
 It is inert.
c.
 It has an atomic mass of 10 daltons.
d.
 A and B only
e.
 A, B, and C are correct.
 24.
From its atomic number of 15, it is possible to predict that the phosphorus atom has
a.
 15 neutrons.
b.
 15 protons.
c.
 15 electrons.
d.
 8 electrons in its outermost electron shell.
e.
 B and C only
Use the figure below to answer the following questions.

nar001-1.jpg
 25.
Which drawing depicts the electron configuration of oxygen (O)?
a.
 Drawing A
b.
 Drawing B
c.
 Drawing C
d.
 Drawing D
e.
 Drawing E
 26.
Which drawing depicts an atom that is inert or chemically unreactive?
a.
 Drawing A
b.
 Drawing B
c.
 Drawing C
d.
 Drawing D
e.
 Drawing E
 27.
Which drawing depicts an atom with a valence of 2?
a.
 Drawing A
b.
 Drawing B
c.
 Drawing C
d.
 Drawing D
e.
 Drawing E
Use the information extracted from the periodic table in the figure below to answer the following questions.

nar002-1.jpg
 28.
How many electrons does nitrogen have in its valence shell?
a.
 2
b.
 5
c.
 7
d.
 8
e.
 14
 29.
How many neutrons are present in the nucleus of a phosphorus atom?
a.
 8
b.
 15
c.
 16
d.
 31
e.
 46
 30.
How many electrons would be expected in the outermost electron shell of an atom with atomic number 12?
a.
 1
b.
 2
c.
 4
d.
 6
e.
 8
 31.
What results from an unequal sharing of electrons between atoms?
a.
 a nonpolar covalent bond
b.
 a polar covalent bond
c.
 an ionic bond
d.
 a hydrogen bond
e.
 a hydrophobic interaction
 32.
A covalent bond is likely to be polar when
a.
 one of the atoms sharing electrons is much more electronegative than the other atom.
b.
 the two atoms sharing electrons are equally electronegative.
c.
 the two atoms sharing electrons are of the same element.
d.
 it is between two atoms that are both very strong electron acceptors.
e.
 the two atoms sharing electrons are different elements.
Use the figure below to answer the following questions. .

nar003-1.jpg
 33.
What results from the chemical reaction?
a.
 a cation with a net charge of +1
b.
 a cation with a net charge of -1
c.
 an anion with a net charge of +1
d.
 an anion with a net charge of -1
e.
 A and D
 34.
What is the atomic number of the cation formed in the reaction?
a.
 1
b.
 8
c.
 10
d.
 11
e.
 16
 35.
In ammonium chloride salt (NH4Cl) the anion is a single chloride ion, . What is the cation of NH4Cl?
a.
 N, with a charge of +3
b.
 H, with a charge of +1
c.
 H2 with a charge of +4
d.
 NH4 with a charge of +1
e.
 NH4 with a charge of +4
 36.
Van der Waals interactions result when
a.
 hybrid orbitals overlap.
b.
 electrons are not symmetrically distributed in a molecule.
c.
 molecules held by ionic bonds react with water.
d.
 two polar covalent bonds react.
e.
 a hydrogen atom loses an electron.
 37.
A van der Waals interaction is the weak attraction between
a.
 the electrons of one molecule and the electrons of a nearby molecule.
b.
 the nucleus of one molecule and the electrons of a nearby molecule.
c.
 a polar molecule and a nearby nonpolar molecule.
d.
 a polar molecule and a nearby molecule that is also polar.
e.
 a nonpolar molecule and a nearby molecule that is also nonpolar.
 38.
Which of the following is not considered to be a weak molecular interaction?
a.
 a covalent bond
b.
 a van der Waals interaction
c.
 an ionic bond in the presence of water
d.
 a hydrogen bond
e.
 A and B only
 39.
An example of a hydrogen bond is the bond between
a.
 C and H in methane (CH4).
b.
 the H of one water molecule and the O of another water molecule.
c.
 Na+and Cl- in salt.
d.
 the two hydrogen atoms in a molecule of hydrogen gas (H2).
e.
 Mg+and Cl- in MgCl2.
 40.
Which of the following is a correct definition of a kilocalorie?
a.
 the amount of heat required to raise the temperature of 1 g of water by 1°F
b.
 the amount of heat required to raise the temperature of 1 g of water by 1°C
c.
 the amount of heat required to raise the temperature of 1 kg of water by 1°F
d.
 the amount of heat required to raise the temperature of 1 kg of water by 1°C
e.
 the amount of heat required to raise the temperature of 1,000 g of water by 1°F
 41.
Desert rabbits are adapted to the warm climate because their large ears aid in the removal of heat due to the
a.
 high surface tension of water.
b.
 high heat of vaporization of water.
c.
 high specific heat of water.
d.
 buffering capacity of water.
e.
 dissociation of water molecules.
 42.
Temperature usually increases when water condenses. Which behavior of water is most directly responsible for this phenomenon?
a.
 the change in density when it condenses to form a liquid or solid
b.
 reactions with other atmospheric compounds
c.
 the release of heat by the formation of hydrogen bonds
d.
 the release of heat by the breaking of hydrogen bonds
e.
 the high surface tension of water
 43.
How many molecules of glucose (C6H2O6 molecular mass =180 daltons) would be present in one mole of glucose?
a.
 24
b.
 342
c.
 23 1014
d.
 180 1014
e.
 6.02 1023

Use the figure below to answer the following questions:

nar004-1.jpg
 44.
How many grams of the molecule in the figure above would be required to make 2.5 L of a 1 M solution of the molecule?
(Carbon = 12, Oxygen = 16, Hydrogen = 1)
a.
 29
b.
 30
c.
 60
d.
 150
e.
 342
 45.
Which of the following ionizes completely in solution and is considered to be a strong base?
a.
 NaCl
b.
 HCl
c.
 NH3
d.
 H2CO3
e.
 NaOH
 46.
A given solution contains 0.0001(10-4) moles of hydrogen ions [H+] per liter. Which of the following best describes this solution?
a.
 acidic: H+ acceptor
b.
 basic: H+ acceptor
c.
 acidic: H+ donor
d.
 basic: H+ donor
e.
 neutral
 47.
A solution contains 0.0000001(10-7) moles of hydroxide ions [OH-] per liter. Which of the following best describes this solution?
a.
 acidic: H+ acceptor
b.
 basic: H+ acceptor
c.
 acidic: H+ donor
d.
 basic: H+ donor
e.
 neutral
 48.
Which of the following solutions has the greatest concentration of hydroxide ions [OH-]?
a.
 lemon juice at pH 2
b.
 vinegar at pH 3
c.
 tomato juice at pH 4
d.
 urine at pH 6
e.
 seawater at pH 8
 49.
Which of the following statements is true about buffer solutions?
a.
 They maintain a constant pH when bases are added to them but not when acids are added to them.
b.
 They maintain a constant pH when acids are added to them but not when bases are added to them.
c.
 They maintain a constant pH of exactly 7 in all living cells and biological fluids.
d.
 They maintain a relatively constant pH.
e.
 They are found only in living systems and biological fluids.
 50.

One of the buffers that contribute to pH stability in human blood is carbonic acid H2CO3. Carbonic acid is a weak acid that when placed in an aqueous solution dissociates into a bicarbonate ion (HCO3-) and a hydrogen ion (H+) Thus,

H2CO3 HCO3- + H+

If the pH of the blood increases, one would expect

a.
 a decrease in the concentration of H2CO3 and an increase in the concentration of H2O.
b.
 an increase in the concentration of H2CO3 and a decrease in the concentration of H2O.
c.
 a decrease in the concentration of HCO3- and an increase in the concentration of H2O.
d.
 an increase in the concentration of HCO3- and a decrease in the concentration of H2O.
e.
 a decrease in the concentration of HCO3- and an increase in the concentration of both H2CO3and H2O.


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Introduction, Chemistry, & Nature of Science Test

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Introduction, Chemistry, & Nature of Science Test
 

Multiple Choice
Identify the choice that best completes the statement or answers the question.
 1.
Biology is the study of
a.
 minerals.
c.
 the weather.
b.
 life.
d.
 energy.
 2.
All organisms possess DNA. DNA
a.
 creates energy for cells.
b.
 allows sensitivity to environmental stimuli.
c.
 contains information for growth and development.
d.
 captures energy from the sun.
 3.
Instructions for traits that are passed from parents to offspring are known as
a.
 a species plan.
c.
 genes.
b.
 organ codes.
d.
 natural selections.
 4.
Homeostasis means
a.
 a change over long periods of time.
b.
 keeping things the same.
c.
 rapid change.
d.
 the same thing as evolution.
 5.
Ecology
a.
 refers to change in species over time.
b.
 refers to a delicate internal balance within organisms.
c.
 is inconsistent with evolution.
d.
 is the study of communities or organisms in relation to their environment.
 6.
Which of the following is not necessarily a characteristic of living things?
a.
 homeostasis
c.
 complexity
b.
 metabolism
d.
 reproduction
 7.
The smallest units that can carry on all the functions of life are called
a.
 molecules.
c.
 organelles.
b.
 cells.
d.
 species.
 8.
Living things
a.
 need energy for life processes.
b.
 have the ability to reproduce.
c.
 are composed of cells.
d.
 All of the above
 9.
All organisms are composed of
a.
 diatoms.
c.
 cells.
b.
 cellulose.
d.
 None of the above
 10.
Which of the following is a characteristic of all living things?
a.
 movement
c.
 development
b.
 photosynthesis
d.
 cellular organization
 11.
Which of the following is not a partial explanation for our lack of understanding of many of the living things on Earth?
a.
 Many organisms are microscopic in size and therefore difficult to observe.
b.
 Many organisms are so different from other organisms that it is difficult to understand them.
c.
 Many organisms live in areas of the world that are difficult to explore.
d.
 Tropical rain forests contain many species, and it is difficult to find all of them in these dense forests.
 12.
A scientist noticed that in acidic pond water some salamanders developed with curved spines. This was a(n)
a.
 hypothesis.
c.
 observation.
b.
 theory.
d.
 control.
 13.
Which example of scientific methodology is incorrect?
a.
 observation—a number of people in a certain place dying of a disease outbreak
b.
 measurement—a record of the number of people with symptoms of a disease and the number of people who had died from the disease
c.
 analysis of data—comparison of the effects of mixing monkey cells with virus-containing blood in test tubes and the effects of mixing liquid from these test tubes with fresh monkey cells
d.
 inference making—identification of the Ebola virus as the cause of a disease by taking electron micrographs of substances found in the blood of persons affected with the disease
 14.
The English physician Ronald Ross wanted to try to find the cause of malaria. Based on his observations, Dr. Ross suggested that the Anopheles mosquito might spread malaria from person to person. This suggestion was a
a.
 prediction.
c.
 theory.
b.
 hypothesis.
d.
 scientific “truth.”
 15.
The English physician Ronald Ross knew that the parasite Plasmodium was always found in the blood of malaria patients. He thought that if the Anopheles mosquitoes were responsible for spreading malaria, then Plasmodium would be found in the mosquitoes. This idea was a
a.
 prediction.
c.
 theory.
b.
 hypothesis.
d.
 scientific “truth.”
 16.
Scientific hypotheses are most often tested by the process of
a.
 communicating.
c.
 experimenting.
b.
 inferring.
d.
 analyzing data.
 17.
A unifying explanation for a broad range of observations is a
a.
 hypothesis.
c.
 prediction.
b.
 theory.
d.
 controlled experiment.
 18.
A hypothesis that does not explain an observation
a.
 is known as an inaccurate forecast.
b.
 often predicts a different observation.
c.
 is rejected.
d.
 None of the above
 19.
Scientists usually design experiments
a.
 with a good idea of the expected experimental results.
b.
 based on wild guesses.
c.
 in order to develop new laboratory tools.
d.
 All of the above
 20.
A scientific theory
a.
 is absolutely certain.
b.
 is unchangeable.
c.
 may be revised as new evidence is presented.
d.
 is a controlled experiment.
 21.
The word theory used in a scientific sense means
a.
 a highly tested, generally accepted principle.
b.
 a guess made with very little knowledge to support it.
c.
 an absolute scientific certainty.
d.
 None of the above
 22.
observation : hypothesis ::
a.
 theory : observation
c.
 hypothesis : experiment
b.
 guess : hypothesis
d.
 theory : control
 23.
Which of the following components of a scientific investigation would benefit from communication between scientists?
a.
 observing
c.
 analyzing data
b.
 measuring
d.
 All of the above
 24.
Typically, the order in which the steps of the scientific method are applied is
a.
 observations, predictions, hypothesis, controlled testing, theory, verification.
b.
 predictions, observations, hypothesis, theory, controlled testing, verification.
c.
 observations, hypothesis, predictions, controlled testing, theory, verification.
d.
 observations, hypothesis, predictions, controlled testing, verification, theory.
 25.
A light microscope that has an objective lens of 10 and an ocular lens of 20 has a magnification of
a.
 30.
c.
 300.
b.
 200.
d.
 2000.
 26.
Which of the following is not a correct association between an SI base unit abbreviation and its base quantity?
a.
 A—area
b.
 m—length
c.
 s—time
d.
 mol—amount of a substance
 27.
Atoms are composed of
a.
 protons with a positive charge.
b.
 neutrons with no charge.
c.
 electrons with a negative charge.
d.
 All of the above
 28.
The smallest particle of carbon that can retain the chemical properties of carbon is
a.
 a carbon molecule.
b.
 a carbon macromolecule.
c.
 a carbon atom.
d.
 the nucleus of a carbon atom.
 29.
A substance that is composed of only one type of atom is called a(n)
a.
 nucleus.
c.
 element.
b.
 cell.
d.
 molecule.
 30.
All matter in the universe is composed of
a.
 cells.
c.
 atoms.
b.
 molecules.
d.
 carbon.
 31.
The electrons of an atom
a.
 are found in the nucleus along with the protons.
b.
 orbit the nucleus in various energy levels.
c.
 have a positive charge.
d.
 are attracted to the positive charge of neutrons.
 32.
Atoms that have gained energy
a.
 have protons and neutrons that move farther apart.
b.
 lose neutrons from the nucleus.
c.
 have electrons that move to higher energy levels.
d.
 absorb electrons into the nucleus.
 33.
Which of the following states of matter contain(s) particles that are tightly linked together in a definite shape?
a.
 solid
c.
 gas
b.
 liquid
d.
 solid and liquid
 34.
Because carbon has four electrons in its outer energy level,
a.
 it can form bonds with carbon atoms only.
b.
 these atoms are naturally chemically stable.
c.
 it can react with up to four other atoms to form covalent bonds.
d.
 it cannot react with anything other than organic molecules.
 35.
The bond formed when two atoms share a pair of electrons is called a
a.
 hydrogen bond.
c.
 covalent bond.
b.
 nonpolar bond.
d.
 water bond.
 36.
Sharing of electrons between atoms of two or more elements
a.
 results in the formation of an ion.
b.
 results in the formation of a compound.
c.
 results in the formation of noble gases.
d.
 results in destabilization of the atoms involved.
 37.
Which of the following statements most accurately describes the difference between an ionic bond and a covalent bond?
a.
 Atoms held together by ionic bonds separate when placed in water, while atoms held together by covalent bonds do not separate in water.
b.
 Ionic bonds hold together atoms of two different types, while covalent bonds hold together atoms of the same type.
c.
 Electrons are exchanged between atoms held together by an ionic bond, but they are shared between atoms held together by a covalent bond.
d.
 Ionic bonds form between atoms that carry opposite charges, while covalent bonds form between uncharged atoms.
nar001-1.jpg
 38.
Refer to the graph above. Reaction 1 in the graph
a.
 is an energy-storing reaction.
b.
 requires a greater activation energy than reaction 2.
c.
 may use the same initial reactant condition needed to form product Y.
d.
 All of the above
 39.
Refer to the graph above. Which of these statements regarding the graph is true?
a.
 Reaction 2 occurs faster than reaction 3 because reaction 2 requires more energy than reaction 3.
b.
 The difference in the graphs shown for reaction 2 and reaction 3 is due to a difference in the activation energy needed for these reactions.
c.
 Reactant X contains more energy at the beginning of the reaction than product Z has after the reaction.
d.
 All of the above
 40.
Changing the course or pathway of a chemical reaction so that it requires less activation energy
a.
 is a violation of the laws of nature.
b.
 requires higher temperatures than those found within cells.
c.
 occurs only when reactants are quickly added to the reaction mixture.
d.
 is accomplished by the action of catalysts on reactants.
 41.
When a molecule gains an electron, it has been
a.
 oxidized.
c.
 digested.
b.
 reduced.
d.
 inactivated.
 42.
The concentration of a solution is
a.
 the number of particles of a substance in a solvent.
b.
 the amount of a solvent that is dissolved in a fixed amount of a solution.
c.
 the amount of a solute that is dissolved in a fixed amount of a solution.
d.
 the ratio of solute to solvent in a solution.
 43.
A neutral solution has an equal number of
a.
 hydrogen and hydronium ions.
b.
 hydroxide and hydronium ions.
c.
 hydrogen and hydroxide ions.
d.
 oxygen and hydrogen ions.
 44.
A solution with a pH of 11 is
a.
 acidic.
c.
 neutral.
b.
 alkaline.
d.
 a buffer.
 45.
Acidic solutions have a pH that is
a.
 less than 7.
c.
 a negative number.
b.
 between 0 and 14.
d.
 more than 7.
 46.
Buffers
a.
 are of relatively little importance in living things.
b.
 are formed when a large number of hydroxide ions are released in a solution.
c.
 are formed when a large number of hydronium ions are released in a solution.
d.
 tend to prevent great fluctuations in pH.
 47.
Atoms become more stable when they form compounds because
a.
 they always lose electrons when they form compounds.
b.
 their outer orbitals become filled when they form compounds.
c.
 they always gain electrons when they form compounds.
d.
 their nucleus loses extra protons when they form compounds.
 48.
A water molecule is polar because its hydrogen and oxygen atoms
a.
 both lose electrons.
b.
 become ions.
c.
 both gain electrons.
d.
 do not share the electrons equally.
 49.
Water molecules break up other polar substances
a.
 such as salts.
b.
 because of the uneven charge distribution that exists in water molecules.
c.
 thus freeing ions in these substances for use by the body.
d.
 All of the above
 50.
Which of the following characteristics of water is not a result of hydrogen bonding?
a.
 adhesive strength
b.
 capillarity
c.
 cohesive strength
d.
 All of the above are a result of hydrogen bonding.


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Cells and Their Functions

Use this question bank to review cell structure, organelles, membranes, transport, and signaling. It retains the original 108 question numbers so teachers can assign selected items.

How to use: Choose one answer, A–E, and record it on paper or in your own answer document. Explain your reasoning for selected questions. This version does not submit, save, or automatically grade responses.

Before starting, review cell parts and their functions and the membrane transport study guide. Teachers should choose items that match their course and review the figures before assigning them.

Learning goals: relate cellular structures to their functions; interpret diagrams and scale; distinguish passive, active, and vesicular transport; and explain how cells communicate.

Cell theory, size, and microscopy

Question 1

The smallest unit that can carry out all activities we associate with life is:

  1. atom.
  2. organelle.
  3. cell.
  4. tissue.
  5. organ.

Question 2

Which observation best illustrates cellular homeostasis?

  1. Organic molecules are present.
  2. Inorganic molecules are present.
  3. All intracellular concentrations change without regulation.
  4. The cell regulates internal conditions within a range despite external changes.
  5. The cell contains no water.

Question 3

Which of the following is not found in single celled organisms?

  1. atoms
  2. cells
  3. tissues
  4. Neither A nor B is found in single celled organisms.
  5. Neither A, nor B, nor C is found in single celled organisms.

Question 4

Evidence that all living cells have a common origin is provided by:

  1. the cell theory, which states that the cell is the basic unit of life.
  2. the fact that all new cells come from previously existing cells.
  3. the fact that cells are the building blocks of the most complex plants.
  4. basic similarities in cell structure and chemistry.
  5. the fact that cells are the smallest units that can carry out all life activities.

Question 5

Which molecule stores the hereditary sequence information used to direct protein synthesis?

  1. proteins
  2. mitochondria
  3. cell membranes
  4. DNA
  5. ribosomes

Question 6

The function of the plasma membrane is to:

  1. serve as a highly selective barrier.
  2. completely isolate the cell from the external environment.
  3. equalize the chemical composition inside and outside the cell.
  4. allow cells to accumulate materials and energy.
  5. Both A and D.

Question 7

It is advantageous for cells to be small because:

  1. a small cell size prevents a cell from weighing too much.
  2. a small cell size occupies less space in nature where space is limited.
  3. a small cell has a small volume relative to surface area, thereby increasing efficient transport.
  4. a small cell has a small surface area relative to volume, thereby facilitating ion balance.
  5. a small cell is better able to conserve energy than a larger cell.
Groups of cube-shaped cells labeled A and B, with side dimensions in micrometers.
Figure 04-01

Question 8

Which of the following statements about Figure 04-01 is true?

  1. Figure B has a greater surface area than Figure A.
  2. Figure B has a greater volume than Figure A.
  3. Figure B has a smaller volume than Figure A.
  4. Figure B has a greater surface area to volume ratio than Figure A.
  5. Figure B has a smaller surface area to volume ratio than Figure A.

Question 9

For the 100 µm cube B in Figure 04-01, what is its surface-area-to-volume ratio in µm⁻¹?

  1. 0.01.
  2. 0.06.
  3. 100.
  4. 1,000.
  5. This cannot be determined from the information provided.

Question 10

One strategy that allows larger cells to have an effective surface area to volume ratio is:

  1. having a completely spherical shape.
  2. being short and fat.
  3. having thin, finger-like projections.
  4. having a thinner plasma membrane.
  5. locomotion.

Question 11

Which statement does not describe cellular homeostasis?

  1. A cell regulates its internal pH within a suitable range.
  2. A cell regulates its internal ion concentrations.
  3. A cell adjusts water balance as conditions change.
  4. A cell uses feedback mechanisms to regulate internal conditions.
  5. A cell allows all internal conditions to vary without regulation.

Question 12

Which of the following descriptions or structures does not match the cell type?

  1. Sperm cells have flagella.
  2. Nerve cells have long, thin extensions.
  3. All epithelial cells have exactly the same shape.
  4. White blood cells can change shape.
  5. All of the above are correct.

Question 13

Which scientist first viewed living cells?

  1. Robert Hooke
  2. Matthias Schleiden
  3. Theodor Schwann
  4. Anton van Leeuwenhoek
  5. August Weismann

Question 14

The ratio of the size of the image seen with the microscope to the actual size of the object is:

  1. magnification.
  2. resolution.
  3. resolving power.
  4. centrifugation.
  5. None of the above.

Question 15

Electron microscopes have a much higher resolution than either the human eye or any light microscope because:

  1. of their higher magnification.
  2. the lenses used are of much higher quality.
  3. the electron beam has a much shorter effective wavelength than visible light.
  4. the images are viewed on screens, rather than directly using an eyepiece or ocular lens.
  5. All of the above.

Question 16

The advantage of studying cells using a phase contrast microscope is that:

  1. the magnification is greater.
  2. the resolving power is greater.
  3. it is faster.
  4. it permits us to view internal structures of live cells.
  5. it uses a beam of electrons to allow us to see the organelles enclosed by the plasma membrane.
Micrograph showing the exterior surface of a ciliated organism, with a 100 micrometer scale bar.
Micrograph for question 17

Question 17

The accompanying figure is the product of a:

  1. phase-contrast light microscope.
  2. Nomarski differential interference microscope.
  3. transmission electron microscope.
  4. scanning electron microscope.
  5. confocal fluorescence microscope.

Question 18

Which feature is especially characteristic of a conventional scanning electron microscope rather than a conventional transmission electron microscope?

  1. It routinely images living specimens.
  2. It uses visible light instead of electrons.
  3. It images internal structures by transmitting electrons through thin sections.
  4. It requires no specimen preparation.
  5. It produces detailed surface images with a three-dimensional appearance.

Question 19

Differential centrifugation is a process that:

  1. separates different components of the cell that function differently.
  2. separates components of the cell that have a different chemical makeup.
  3. analyzes the chemical components of the cell.
  4. separates cell components by differences in sedimentation rate, influenced by size and density.
  5. allows researchers to view the contents of the cells.

Cell structures and organelles

Question 20

Which structure is found in eukaryotic cells but is absent from prokaryotic cells?

  1. cell wall
  2. flagellum
  3. ribosomes
  4. Golgi apparatus
  5. DNA

Question 21

Membrane-bounded organelles facilitate faster chemical reactions because:

  1. reactants are within close proximity to each other.
  2. membranes lower the activation energy of biochemical reactions.
  3. membrane-bounded organelles act as catalysts for biochemical reactions.
  4. reactants move faster within membrane-bounded organelles.
  5. reactants are less likely to encounter each other within membrane-bounded organelles.

Question 22

A eukaryotic cell:

  1. is usually smaller than a prokaryotic cell.
  2. has its DNA concentrated in one area of the cell without a nuclear membrane.
  3. typically has a cell wall, in addition to a plasma membrane.
  4. is a bacteria-like organism.
  5. has a variety of membranous organelles.

Question 23

Which task is performed by genetic sequence information rather than being a direct function of cellular membranes?

  1. facilitating the formation of energy-yielding gradients.
  2. acting as barriers to ions.
  3. acting as important "work benches" within cells.
  4. specifying the amino-acid sequence of a protein.
  5. maintaining the identity of different cellular compartments.

Question 24

Which structure is generally absent from ordinary nonphotosynthetic cells in underground plant roots?

  1. mitochondria
  2. chloroplasts
  3. endoplasmic reticulum
  4. nucleus
  5. All of the above would be found in cells of a plant's root.

Question 25

Which organelle-function pairing is incorrect?

  1. Mitochondria: ATP production associated with cellular respiration.
  2. Ribosomes: assembly of polypeptides.
  3. Smooth endoplasmic reticulum: assembly of polypeptides from amino acids.
  4. Chloroplasts: photosynthesis in plant leaf cells.
  5. Golgi apparatus: modification and sorting of proteins.

Question 26

Which organelle is not part of the endomembrane system?

  1. smooth endoplasmic reticulum
  2. lysosome
  3. transport vesicle
  4. peroxisome
  5. Golgi apparatus

Question 27

DNA is associated with proteins, forming a complex known as:

  1. chromosomes.
  2. nucleoli.
  3. nucleus.
  4. genes.
  5. chromatin.

Question 28

In the classic experiments by Bracht and Hammerling, the nucleus of Acetabularia was removed, the cap was cut off, a nucleus of a different species was inserted, and the cap was allowed to regenerate. The new cap was then removed. After the second regeneration, the cap was observed, and the following conclusion was made:

  1. The shape of the cap was controlled by the nucleus, thus, the nucleus was the control center of the cell.
  2. The shape of the cap was under the control of the stalk, which produced a control substance.
  3. The shape of the cap was independent of both the stalk and the holdfast.
  4. The "cren" caps were defective due to some mutation in the cap. Thus, "cren" caps are independent of control from both the base and the holdfast.
  5. At the time no conclusion could be made because in the early 20th century, biologists did not know about the composition of DNA.

Question 29

Chromosomal regions within the nucleolus include genes transcribed to produce which major component of ribosomes?

  1. cellulose
  2. ribosomal RNA (rRNA)
  3. phospholipids
  4. glycogen
  5. cholesterol

Question 30

If a toxin, such as a bacterial toxin, destroys ribosomes, what cellular activity will be affected first?

  1. protein synthesis
  2. DNA synthesis
  3. movement
  4. energy storage
  5. active transport

Question 31

Proteins made on ribosomes may be further modified within the:

  1. lysosomes.
  2. nucleus.
  3. mitochondria.
  4. Golgi complex.
  5. peroxisomes.

Question 32

The smooth endoplasmic reticulum:

  1. is absent in most plant cells.
  2. synthesizes proteins.
  3. provides structural support.
  4. synthesizes lipids.
  5. is required for ribosome synthesis.
Membrane network with an arrow pointing to surface particles and a boxed region.
Figure 04-02

Question 33

The cellular structure indicated by the arrow in Figure 04-02 is responsible for:

  1. lipid and fatty acid metabolism.
  2. protein synthesis.
  3. digestion of unused organelles.
  4. replication.
  5. None of the above.

Question 34

Which of the following statements about the structure surrounded by the box in Figure 04-02 is true?

  1. This structure is only found in plant cells.
  2. This structure is characteristic of both prokaryotic and eukaryotic cells.
  3. This structure plays a central role in the process of transcription.
  4. This structure typically represents a significant portion of the overall cell volume.
  5. This structure represents the main storage area for the cell.

Question 35

Which of the following pairs is correctly matched?

  1. chloroplast – storage of enzymes
  2. lysosome – powerhouse of the cell
  3. nucleolus – site of ribosomal subunit synthesis
  4. plastids – structural support of the cell
  5. Golgi complex – production of energy

Question 36

Which of the following organelles plays an important role in apoptosis, or programmed cell death?

  1. ribosomes
  2. mitochondria
  3. chloroplasts
  4. vacuoles
  5. peroxisomes

Question 37

One function of peroxisomes involves the process of:

  1. cell death.
  2. water storage.
  3. protein synthesis.
  4. DNA replication.
  5. detoxification.

Question 38

During an infection, white blood cells travel to the infected site and phagocytize the pathogens. After phagocytosis, primary lysosomes fuse with the phagocytic vesicle to form a larger vesicle called a secondary lysosome. The reason for this is:

  1. to introduce antibodies to the phagocytic vesicles.
  2. to wrap the pathogen in additional membrane, rendering them harmless.
  3. to coat the bacteria in lipids derived from the Golgi complex, which cover and smother them.
  4. to mix the pathogens with strong hydrolytic enzymes and destroy them.
  5. to prepare the bacteria for export from the body.

Question 39

All of the following functions are performed by plant vacuoles except:

  1. maintaining hydrostatic (turgor) pressure.
  2. waste storage and recycling.
  3. storage of proteins.
  4. breakdown of unneeded cellular materials.
  5. storage of nucleic acids.

Question 40

The theory that chloroplasts and mitochondria had their evolutionary beginnings in eukaryotic cells as endosymbionts is supported by all of the following except:

  1. chloroplasts and mitochondria are completely autonomous within eukaryotic cells.
  2. chloroplasts and mitochondria have DNA.
  3. chloroplasts and mitochondria have small ribosomes for protein synthesis.
  4. chloroplasts and mitochondria are approximately the same size as prokaryotic cells.
  5. chloroplasts and mitochondria contain genetic material with features related to bacterial genetic material.

Question 41

A cellular structure found in plant but not animal cells is the:

  1. chloroplast.
  2. ribosome.
  3. endoplasmic reticulum.
  4. microtubule.
  5. microfilament.
Cutaway chloroplast diagram with labeled structures A through E.
Figure 04-03

Question 42

Refer to Figure 04-03. The formation of ATP occurs in the portion of the chloroplast labeled:

  1. structure A.
  2. structure B.
  3. structure C.
  4. structure D.
  5. structure E.

Question 43

The formation of carbohydrates from carbon dioxide and water occurs in the portion of the chloroplast in Figure 04-03 labeled:

  1. structure A.
  2. structure B.
  3. structure C.
  4. structure D.
  5. structure E.

Question 44

Which of the following is a key component of the cytoskeleton?

  1. membranes
  2. microtubules
  3. DNA
  4. ribosomes
  5. None of the above.

Question 45

The force necessary to cause microtubules of cilia and flagella to slide alongside one another is provided through the action of _________ proteins, which derive the energy to perform their work directly from ______ molecules.

  1. kinesin; ADP
  2. kinesin; glucose
  3. tubulin; ATP
  4. dynein; ATP
  5. dynein; ADP
Cross-sections of cylindrical cellular structures with a 0.5 micrometer scale bar.
Micrograph for question 46

Question 46

The structures in the micrograph could be:

  1. chloroplasts.
  2. cilia.
  3. RER.
  4. flagella.
  5. B and D
Cutaway organelle diagram with arrows pointing to folds of the inner membrane.
Figure 04-04

Question 47

The organelle featured in Figure 04-04:

  1. is present in a few prokaryotes.
  2. is the major site of protein synthesis in the cell.
  3. plays a vital role in packaging materials to be secreted.
  4. plays a central role in energy metabolism.
  5. is located in the nucleus.

Question 48

The structures indicated by the arrows in Figure 04-04 are:

  1. thylakoid lamellae.
  2. grana.
  3. cristae.
  4. matrices.
  5. plastids.

Question 49

The main process that occurs at the site of the structures marked by arrows in Figure 04-04 is:

  1. protein synthesis.
  2. photosynthesis.
  3. conversion of food molecules to ATP.
  4. processing and packaging of proteins.
  5. transcription.

Question 50

A single cell in a smoker's lung has become cancerous. It doubles its DNA and divides much faster than a normal lung cell. The most likely change that would have caused this condition took place in the:

  1. nucleus.
  2. nucleolus.
  3. microtubule.
  4. mitochondria.
  5. lysosome.

Question 51

Cells have internal structures called organelles. Which is not a function of organelles?

  1. Store genetic information.
  2. Convert energy to more usable forms.
  3. Synthesize polymers.
  4. Manufacture membranes.
  5. All of the above are organelle functions.

Question 52

Which of the following is not a cell covering or part of a cell covering?

  1. glycocalyx
  2. extracellular matrix
  3. cristae
  4. cell wall
  5. integrins

Question 53

The principle cell adhesion molecules in vertebrates and in many invertebrates are cadherins. These are important in:

  1. preventing the invasiveness of some malignant tumors.
  2. calcium-dependent adhesion between cells that form multicellular sheets.
  3. embryonic development.
  4. cell adhesion in vertebrates and in many invertebrates.
  5. All of the above.

Membranes and transport proteins

Question 54

All of the following are functions of the cell membrane except:

  1. transmitting signals.
  2. participating in energy transfer.
  3. being freely permeable.
  4. regulating the passage of materials.
  5. participating in chemical reactions.

Question 55

Which of the following structures is composed of two layers of phospholipids associated with proteins integrated within or attached to these layers?

  1. cell wall
  2. plasma membrane
  3. microfilaments
  4. flagellum
  5. ribosomes

Question 56

Phospholipids can form bilayer structures because of their:

  1. rectangular shapes.
  2. amphipathic nature.
  3. ability to dissolve well in water.
  4. inability to associate with other phospholipids.
  5. lack of fatty acids.

Question 57

Phospholipids can form bilayers because the molecules:

  1. have two distinct regions, one strongly hydrophobic and the other strongly hydrophilic.
  2. are amphipathic molecules.
  3. have cylindrical shapes that allow them to associate with water most easily as a bilayer structure.
  4. Both A and B.
  5. A, B, and C.

Question 58

A key discovery that weakened the Davson-Danielli "sandwich" model of cell membranes was that:

  1. membrane proteins form a solid sheet on either side of the phospholipid bilayer.
  2. membrane proteins form a solid sheet separating the phospholipid layer.
  3. the phospholipids do not associate with each other in the hydrophobic region of membranes.
  4. membrane proteins were not uniform and did not form flattened sheets.
  5. membrane proteins occurred in regular organized patterns on the surface of membranes.

Question 59

Proposed the fluid mosaic model of cell membrane structure in 1972:

  1. S. Jonathan Singer.
  2. Garth Nicolson.
  3. Hugh Davson.
  4. Both A and B.
  5. A, B, and C.

Question 60

Which is a typical lipid component of an animal cell plasma membrane?

  1. DNA
  2. glucose
  3. cholesterol
  4. water
  5. All of the above.

Question 61

Cholesterol within membranes functions as a(an) ____________ through its interactions with both hydrophobic and hydrophilic parts of phospholipids.

  1. water blocker
  2. pH buffer
  3. energy source
  4. temperature controller
  5. fluidity buffer

Question 62

In a lipid bilayer, ___________ fatty acid tails face each other within the bilayer and form a region that excludes water.

  1. hypertonic
  2. hyperosmotic
  3. hypotonic
  4. hydrophilic
  5. hydrophobic

Question 63

Which of the following functions best explains the reason for the asymmetrically oriented structure of the proteins in the cell membrane?

  1. These proteins are manufactured by free ribosomes.
  2. Each type of protein has its own function.
  3. These proteins pass through the ER membrane into the ER lumen.
  4. Enzymes are needed to modify the carbohydrate chains on these proteins.
  5. These proteins are initially formed by ribosomes on the rough ER.

Question 64

Which of the following is not a function associated with membrane proteins?

  1. Recognition of surface antigens of bacterial cells.
  2. Forming junctions between adjacent cells.
  3. Identify the cell as belonging to a particular individual.
  4. Serve as anchoring points for networks of cytoskeletal elements.
  5. All of the above are functions associated with membrane proteins.

Question 65

Which statement best describes the function of aquaporins?

  1. They pump water against its gradient using ATP directly.
  2. They form channels that facilitate passive water movement across a membrane.
  3. They synthesize phospholipids.
  4. They digest proteins inside lysosomes.
  5. They carry DNA into the nucleus.

Question 66

Catalysts are reusable. Enzymes are protein catalysts, and are reusable. Select the protein(s) below that is (are) not used up by the process carried out:

  1. Sodium-potassium pump carrier proteins
  2. Aquaporins
  3. Proteins involved in facilitated diffusion
  4. Both A and B.
  5. A, B, and C.

Question 67

Integral proteins:

  1. are weakly bound to the surface of the membrane.
  2. are strongly bound to the cytosolic surface of the membrane.
  3. have no hydrophobic portions.
  4. are completely embedded within the lipid bilayer.
  5. are amphipathic.

Question 68

What is meant by the term "fluid mosaic model"?

  1. It is the diffusion of lipid-soluble substances through the lipid bilayer.
  2. It is the movement of lipids and integral proteins within the lipid bilayer.
  3. It is the solubility of water in the membrane.
  4. It is the method of substance transport across the membrane.
  5. It is the movement of surface proteins through the membrane.

Question 69

A transmembrane protein differs from other membrane proteins because it:

  1. is covalently linked to the outer surface of the plasma membrane.
  2. is a glycoprotein with carbohydrates attached.
  3. is attached to the inside of the membrane by an ionic bond .
  4. completely extends through the membrane.
  5. is completely embedded within the membrane.

Question 70

Peripheral proteins are linked to either surface of the plasma membrane by:

  1. covalent disulfide bonds.
  2. associating with fatty acids through hydrophobic interactions.
  3. embedding in one side of the membrane and, thus, not extending through to the other side.
  4. associating with glycoproteins on the inner membrane surface.
  5. bonding to integral proteins through weak linkages.

Question 71

Which of the following statements explaining the differences in number and types of peripheral proteins found on the inner and outer surfaces of cell membranes is correct?

  1. The functions of the membrane differ on the inside and outside of the cell.
  2. Not all proteins can pass through the membrane and, thus, more accumulate on the inside.
  3. Proteins on the outside of the membrane are synthesized at a slower rate than proteins on the inside of the membrane.
  4. Proteins on the outside of membrane are made extracellularly and are unable to penetrate the phospholipid bilayer and enter the cell.
  5. The external peripheral proteins are weakly attached to the membrane and are readily washed away.

Question 72

Proteins that are destined to become associated with the inner surface of the plasma membrane are:

  1. manufactured in the same way as protein hormones.
  2. manufactured in the same way as proteins destined to become external peripheral proteins.
  3. made on free ribosomes in the cytoplasm.
  4. made on ribosomes located on the rough endoplasmic reticulum.
  5. transported to the plasma membrane within a secretory vesicle.

Diffusion, osmosis, and transport

Question 73

Biological membranes are normally permeable to:

  1. large, hydrophilic molecules.
  2. small, hydrophilic molecules.
  3. large, hydrophobic molecules.
  4. small, hydrophobic molecules.
  5. None of the above.

Question 74

A bottle of perfume is opened on the opposite side of the room and within minutes you begin to smell the perfume. This phenomenon is a classic example of:

  1. dialysis.
  2. osmosis.
  3. active transport.
  4. facilitated diffusion.
  5. diffusion.

Question 75

Which of the following molecules is least likely to cross a cellular membrane by simple diffusion?

  1. carbon dioxide
  2. nitrogen
  3. oxygen
  4. potassium ion
  5. water

Question 76

The passive movement of a substance along its concentration gradient is termed:

  1. active transport.
  2. dialysis.
  3. diffusion.
  4. exocytosis.
  5. osmosis.

Question 77

Which type of molecule generally passes most readily through the hydrophobic core of a phospholipid bilayer without a transport protein?

  1. small polar molecules
  2. small nonpolar molecules
  3. large polar molecules
  4. large nonpolar molecules
  5. water

Question 78

The difference between dialysis and osmosis is that:

  1. in osmosis, the solute moves through a selectively permeable membrane.
  2. in dialysis, the solvent moves through a selectively permeable membrane.
  3. in osmosis, the solute moves from a region of high concentration to a region of low concentration.
  4. in dialysis, the solute moves from a region of high concentration to a region of low concentration.
  5. in dialysis, the solvent moves from a region of high concentration to a region of low concentration through a selectively permeable membrane.

Question 79

If the concentration of solutes in a cell is less than the concentration of solutes in the surrounding fluid, then the extracellular fluid is said to be:

  1. hypertonic.
  2. hypotonic.
  3. isotonic.
  4. stable.
  5. amphipathic.

Question 80

The higher the concentration of solute in a solution, the _________ the effective water concentration and the ________ the osmotic pressure.

  1. lower; lower
  2. lower; higher
  3. higher; higher
  4. higher; lower
  5. Answer cannot be determined from the information provided.
Red blood cells in beakers and micrographs labeled samples A and B.
Figure 05-01

Question 81

Which of the following statements about the red blood cells in Figure 05-01 Sample B is true?

  1. These red blood cells have been placed in an isotonic solution.
  2. These red blood cells have swollen in response to a hypertonic external solution.
  3. These red blood cells have swollen in response to a hypotonic external solution.
  4. These red blood cells have shrunken in response to a hypertonic external solution.
  5. These red blood cells have shrunken in response to a hypotonic external solution.

Question 82

Which of the following statements about the red blood cells in Figure 05-01 Sample A is true?

  1. There has been no net water movement.
  2. There has been a net flow of water out of the cell.
  3. There has been a net flow of water into the cell.
  4. Pinocytosis has occurred.
  5. Plasmolysis has occurred.

Question 83

A patient who has had a severe hemorrhage accidentally receives a large transfusion of distilled water directly into a major blood vessel. You would expect this mistake to:

  1. have no unfavorable effect as long as the water is free of bacteria.
  2. have serious, perhaps fatal consequences because there would be too much fluid to pump.
  3. have serious, perhaps fatal consequences because the red blood cells could shrink.
  4. have serious, perhaps fatal consequences because the red blood cells could swell and burst.
  5. have no serious effect because the kidney could quickly eliminate excess water.

Question 84

A plant cell placed in a hypertonic solution will:

  1. remain unchanged.
  2. undergo lysis.
  3. undergo plasmolysis.
  4. swell slightly.
  5. become crenated.

Question 85

Penicillin is toxic to certain dividing bacterial cells because it prevents cell wall formation, causing the cells to burst. This indicates that the bacteria live in:

  1. a hypotonic medium.
  2. a hypertonic medium.
  3. an isotonic medium.
  4. a medium with higher osmotic pressure than the cell.
  5. Both B and D.

Question 86

A wilted flower placed in a vase of water for several hours became stiff and stood erect. When it was placed in a salt solution, it wilted. From this information we can say that the cells of the flower are:

  1. hypotonic to both fresh water and the salt solution.
  2. hypertonic to both the fresh water and the salt solution.
  3. hypertonic to fresh water but hypotonic to the salt solution.
  4. hypotonic to fresh water but hypertonic to the salt solution.
  5. isotonic to fresh water but hypotonic to the salt solution.

Question 87

Which of the following membrane activities does not require the expenditure of energy by the cell?

  1. active transport
  2. osmosis
  3. endocytosis
  4. exocytosis
  5. synthesis of more membrane

Question 88

Facilitated diffusion:

  1. requires a transmembrane protein.
  2. requires ATP.
  3. can move molecules against a concentration gradient.
  4. is typically used to transport small nonpolar molecules.
  5. All of the above.

Question 89

A bacterium accumulates sodium ions uphill against their electrochemical gradient. Which mechanism can drive this accumulation?

  1. active transport.
  2. endocytosis.
  3. diffusion.
  4. facilitated diffusion.
  5. osmosis.

Question 90

The energy-requiring movement of materials against a concentration gradient is termed:

  1. active transport.
  2. dialysis.
  3. facilitated diffusion.
  4. osmosis.
  5. plasmolysis.

Question 91

Which immediate conversion helps maintain a low concentration of free glucose inside a cell after glucose enters?

  1. conversion of glucose directly into protein
  2. excretion of glucose into the surrounding fluid
  3. phosphorylation of glucose to glucose-6-phosphate
  4. active pumping of all glucose out of the cell
  5. engulfment of glucose by pinocytosis

Question 92

Which of the following statements about the sodium-potassium pump is true?

  1. It transports hydrogen ions out of the cell.
  2. It transports 3 sodium ions out of the cell in exchange for 2 potassium ions.
  3. It transports 2 sodium ions out of the cell in exchange for 2 potassium ions.
  4. It transports 2 sodium ions out of the cell in exchange for 3 potassium ions.
  5. It transports water directly out of the cell.

Question 93

A person has a genetic disease that prevents the phospholipids in the plasma membrane of the white blood cells from freely fusing with the other membranes within the cell. How would this disease affect phagocytosis?

  1. Lysosomes would not be formed.
  2. Facilitated diffusion would not occur.
  3. Lysosomes would be formed lacking hydrolytic enzymes.
  4. The phagocytic vacuole would not fuse with the lysosome.
  5. Endocytosis would not occur.

Question 94

Which of the following are forms of carrier-mediated transport?

  1. Facilitated diffusion.
  2. Carrier-mediated active transport.
  3. Osmosis.
  4. Both A and B.
  5. A, B, and C.

Question 95

Which statement describes facilitated diffusion itself?

  1. A substance moves downhill through a channel or carrier without direct ATP use by that transport step.
  2. A substance is pumped uphill against its electrochemical gradient.
  3. ATP must bind and be hydrolyzed in every transport cycle.
  4. Transport requires a membrane vesicle.
  5. Only small nonpolar molecules can be transported.

Vesicles, junctions, and cell signaling

Question 96

Pinocytosis:

  1. is engulfment of large particles by the cell.
  2. occurs in protozoans and algae but not in more complex organisms.
  3. involves the specific binding of molecules to receptors on the cell surface.
  4. is the nonspecific uptake of fluids by an invagination of the cell membrane.
  5. is movement of molecules against the concentration gradient through a permeable membrane.

Question 97

Receptor-mediated endocytosis:

  1. is a passive process.
  2. involves only membrane transport proteins.
  3. brings about the selective uptake of materials by enclosing them in membranous vesicles.
  4. does not require energy.
  5. is most likely to be found in cells that release large amounts of hormones.

Question 98

A human white blood cell engulfs a bacterial cell by:

  1. carrier-mediated facilitated diffusion.
  2. exocytosis.
  3. phagocytosis.
  4. pinocytosis.
  5. the sodium-potassium pump.

Question 99

Which event occurs before a coated vesicle forms during receptor-mediated endocytosis?

  1. The incoming cargo is digested in a lysosome.
  2. A ligand binds to a receptor at the cell surface.
  3. The vesicle releases its cargo outside the cell by exocytosis.
  4. The newly internalized receptor is recycled to the surface.
  5. The ligand separates from its receptor inside an endosome.

Question 100

In cells that are constantly involved in secretion, an equivalent amount of membrane must be returned to the interior of the cell for each vesicle that fuses with the plasma membrane; if this does not occur, then what would happen?

  1. The ratio of cell surface would decrease, compared to cell volume.
  2. The cell surface would shrivel.
  3. The surface area would remain constant.
  4. The number of membrane receptor proteins would decrease.
  5. The cell surface will keep expanding.
Three numbered stages showing a vesicle approaching and merging with a plasma membrane.
Figure 05-02

Question 101

The process illustrated in Figure 05-02 is called:

  1. facilitated diffusion.
  2. pinocytosis.
  3. cotransport.
  4. lysis.
  5. exocytosis.

Question 102

The process illustrated in Figure 05-02 would most likely be used to transport:

  1. glucose.
  2. hormones.
  3. potassium ions.
  4. carbon dioxide.
  5. bacteria.

Question 103

One difference between tight junctions and desmosomes is that tight junctions:

  1. form continuous seals that restrict movement between neighboring epithelial cells.
  2. occur only in plants.
  3. involve connective microfilaments that traverse the space between adjacent cells.
  4. are anchored by microfilaments on the insides of the cell membranes of adjacent cells.
  5. contain a 24 nm space between two adjacent membranes.

Question 104

Plasmodesmata of plant cells are functionally equivalent to ____________ of animal cells.

  1. gap junctions
  2. desmosomes
  3. tight junctions
  4. cell surface receptors
  5. microvilli
Adjacent cell membranes connected by channel-like complexes.
Diagram for question 105

Question 105

The structures in this figure:

  1. provide anchorage points between adjacent cells.
  2. allow the transport of small molecules and ions between adjacent cells.
  3. allow passage of materials through intercellular spaces.
  4. prevent the passage of materials through intercellular spaces.
  5. can only be found in plants.

Question 106

Which of the following is not part of the process of cell signaling?

  1. Synthesis and release of signaling molecules.
  2. Facilitated transport.
  3. Transport to target cells.
  4. Response by the cell.
  5. Termination of signaling.

Question 107

The process in which cells convert and amplify an extracellular signal into an intracellular signal:

  1. Synthesis and release of signaling molecules.
  2. Transport to target cells.
  3. Signal transduction.
  4. Response by the cell.
  5. Termination of signaling.

Question 108

In a signaling pathway, the second messenger is often:

  1. GTP.
  2. GDP.
  3. cyclic AMP.
  4. cyclic ADP.
  5. ATP.

Teacher notes and sources

This is a classroom question bank, not a timed online test. No complete answer key is supplied. Use a separate answer sheet and discuss the evidence for each selected response. Small, inherited image labels may be easier to read at full size. Retain existing figure credits and check permissions before redistributing the figures.

For the membrane-protein terminology in question 69, see the existing ionic bond resource.

Return to Cells and Transport Teaching Resources.

AP Introduction, Chemistry, and Water

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AP Introduction, Chemistry, and Water
  

Multiple Choice
Identify the choice that best completes the statement or answers the question.
 
   
 
Self-Quiz Questions
 
 1.
All organisms on your campus make up
a.
 an ecosystem.
b.
 a community.
c.
 a population.
d.
 an experimental group.
e.
 a taxonomic domain.
 
 2.
Which of the following is a correct sequence of levels in life’s hierarchy, proceeding downward from an individual animal?
a.
 brain, organ system, nerve cell, nervous tissue
b.
 organ system, population of cells, nervous tissue, brain
c.
 organism, organ system, tissue, cell, organ
d.
 nervous system, brain, nervous tissue, nerve cell
e.
 organ system, tissue, molecule, cell
 
 3.
Which of the following is not an observation or inference on which Darwin’s theory of natural selection is based?
a.
 Poorly adapted individuals never produce offspring.
b.
 There is heritable variation among individuals.
c.
 Because of overproduction of offspring, there is competition for limited resources.
d.
 Individuals whose inherited characteristics best fit them to the environment will generally produce more offspring.
e.
 A population can become adapted to its environment.
 
 4.
Systems biology is mainly an attempt to
a.
 understand the integration of all levels of biological organization from molecules to the biosphere.
b.
 simplify complex problems by reducing the system into smaller, less complex units.
c.
 model one level of biological organization based on an understanding of the lower levels of organization.
d.
 provide a systematic method for interpretation of large amounts of biological data.
e.
 speed up the technological application of scientific knowledge.
 
 5.
Protists and bacteria are grouped into different domains because
a.
 protists eat bacteria.
b.
 bacteria are not made of cells.
c.
 bacterial cells lack a nucleus.
d.
 bacteria decompose protists.
e.
 protists are photosynthetic.
 
 6.
Which of the following best demonstrates the unity among all organisms?
a.
 matching DNA nucleotide sequences
b.
 descent with modification
c.
 the structure and function of DNA
d.
 natural selection
e.
 emergent properties
 
 7.
Which of the following is an example of qualitative data?
a.
 The temperature decreased from 20°C to 15°C.
b.
 The plant’s height is 25 centimeters.
c.
 The fish swam in a zig-zag motion.
d.
 The six pairs of robins hatched an average of three chicks.
e.
 The contents of the human stomach are mixed about every 20 seconds.
 
 8.
Which of the following best describes the logic of hypothesis-based science?
a.
 If I generate a testable hypothesis, tests and observations will support it.
b.
 If my prediction is correct, it will lead to a testable hypothesis.
c.
 If my observations are accurate, they will support my hypothesis.
d.
 If my hypothesis is correct, I can expect certain test results.
e.
 If my experiments are set up right, they will lead to a testable hypothesis.
 
 9.
A controlled experiment is one that
a.
 proceeds slowly enough that a scientist can make careful records of the results.
b.
 may include experimental groups and control groups tested in parallel.
c.
 is repeated many times to make sure the results are accurate.
d.
 keeps all environmental variables constant.
e.
 is supervised by an experienced scientist.
 
 10.
Which of the following statements best distinguishes hypotheses from theories in science?
a.
 Theories are hypotheses that have been proved.
b.
 Hypotheses are guesses; theories are correct answers.
c.
 Hypotheses usually are relatively narrow in scope; theories have broad explanatory power.
d.
 Hypotheses and theories are essentially the same thing.
e.
 Theories are proved true in all cases; hypotheses are usually falsified by tests.
 
 11.
An element is to a (an) ____ as an organ is to a (an) ____.
a.
 atom; organism
b.
 compound; organism
c.
 molecule; cell
d.
 atom; cell
e.
 compound; organelle
 
 12.
In the term trace element, the modifier trace means
a.
 the element is required in very small amounts.
b.
 the element can be used as a label to trace atoms through an organism’s metabolism.
c.
 the element is very rare on Earth.
d.
 the element enhances health but is not essential for the organism’s long-term survival.
e.
 the element passes rapidly through the organism.
 
 13.
Compared to 31P, the radioactive isotope 32P has
a.
 a different atomic number.
b.
 one more neutron.
c.
 one more proton.
d.
 one more electron.
e.
 a different charge.
 
 14.
Atoms can be represented by simply listing the number of protons, neutrons, and electrons-for example, 2p+; 2n0; 2e- for helium. Which atom represents the 18O isotope of oxygen?
a.
 6p+; 8n0; 6e-
b.
 8p+; 10n0; 8e-
c.
 9p+; 9n0; 9e-
d.
 7p+; 2n0; 9e-
e.
 10p+; 8n0; 9e-
 
 15.
The atomic number of sulfur is 16. Sulfur combines with hydrogen by covalent bonding to form a compound, hydrogen sulfide. Based on the electron configuration of sulfur, we can predict that the molecular formula of the compound will be ____.
a.
 HS
b.
 HS2
c.
 H2S
d.
 H3S2
e.
 H4S
 
 16.
Review the valences of carbon, oxygen, hydrogen, and nitrogen, and then determine which of the following molecules is most likely to exist.
a.
 O = C-H
b.
 H   H
|     |
H – O – C – C = O
|
H
c.
 H      H
|      |
H- C- H – C = O
|
H
d.
 O
|
H – N = H
 
 17.
The reactivity of an atom arises from
a.
 the average distance of the outermost electron shell from the nucleus.
b.
 the existence of unpaired electrons in the valence shell.
c.
 the sum of the potential energies of all the electron shells.
d.
 the potential energy of the valence shell.
e.
 the energy difference between the s and p orbitals.
 
 18.
Which of these statements is true of all anionic atoms?
a.
 The atom has more electrons than protons.
b.
 The atom has more protons than electrons.
c.
 The atom has fewer protons than does a neutral atom of the same element.
d.
 The atom has more neutrons than protons.
e.
 The net charge is 1-.
 
 19.
What coefficients must be placed in the blanks so that all atoms are accounted for in the products? 

C6H12O6 ____C2H6O + ____CO2

a.
 1; 2
b.
 2; 2
c.
 1; 3
d.
 1; 1
e.
 3; 1
 
 20.
Which of the following statements correctly describes any chemical reaction that has reached equilibrium?
a.
 The concentration of products equals the concentration of reactants.
b.
 The rate of the forward reaction equals the rate of the reverse reaction.
c.
 Both forward and reverse reactions have halted.
d.
 The reaction is now irreversible.
e.
 No reactants remain.
 
 21.
What is the best explanation of the phrase “fitness of the environment” as used in this chapter?
a.
 Earth’s environment is constant.
b.
 It is the physical environment, not life, that has changed.
c.
 The environment of Earth has adapted to life.
d.
 Life as we know it depends on certain environmental qualities on Earth.
e.
 Water and other aspects of Earth’s environment exist because they make the planet more suitable for life.
 
 22.
Many mammals control their body temperature by sweating. Which property of water is most directly responsible for the ability of sweat to lower body temperature?
a.
 water’s change in density when it condenses
b.
 water’s ability to dissolve molecules in the air
c.
 the release of heat by the formation of hydrogen bonds
d.
 the absorption of heat by the breaking of hydrogen bonds
e.
 water’s high surface tension
 
 23.
For two bodies of matter in contact, heat always flows from
a.
 the body with greater heat to the one with less heat.
b.
 the body of higher temperature to the one of lower temperature.
c.
 the denser body to the less dense body.
d.
 the body with more water to the one with less water.
e.
 the larger body to the smaller body.
 
 24.
A slice of pizza has 500 kcal. If we could burn the pizza and use all the heat to warm a 50-L container of cold water, what would be the approximate increase in the temperature of the water? (Note: A liter of cold water weighs about 1 kg).
a.
 50°C
b.
 5°C
c.
 10°C
d.
 100°C
e.
 1°C
 
 25.
The bonds that are broken when water vaporizes are
a.
 ionic bonds.
b.
 bonds between water molecules.
c.
 bonds between atoms within individual water molecules.
d.
 polar covalent bonds.
e.
 nonpolar covalent bonds.
 
 26.
Which of the following is an example of a hydrophobic material?
a.
 paper
b.
 table salt
c.
 wax
d.
 sugar
e.
 pasta
 
 27.
We can be sure that a mole of table sugar and a mole of vitamin C are equal in their
a.
 mass in daltons.
b.
 mass in grams.
c.
 number of molecules.
d.
 number of atoms.
e.
 volume.
 
 28.
How many grams of acetic acid (C2H4O2)would you use to make 10 L of a 0.1 M aqueous solution of acetic acid? (Note: The atomic masses, in daltons, are approximately 12 for carbon, 1 for hydrogen, and 16 for oxygen.)
a.
 10.0 g
b.
 0.1 g
c.
 6.0 g
d.
 60.0 g
e.
 0.6 g
 
 29.
Acid precipitation has lowered the pH of a particular lake to 4.0. What is the hydrogen ion concentration of the lake?
a.
  
b.
  
c.
  
d.
  
e.
 4%
 
 30.
What is the hydroxide ion concentration of the lake described in question 9?
a.
  
b.
  
c.
  
d.
  
e.
 10 M
 

 

 
         Start Over

Scientific Method Web Quest: Compare Questions, Methods, and Evidence

Biology Foundations and Lab Skills Teaching Resources · High school biology; AP extensions where noted.

This guided reading task asks students to compare descriptions of scientific inquiry and then design a testable investigation on paper. The aim is to explain how evidence is used, rather than copy a list of steps from a website.

Learning goals and preparation

  • Distinguish questions, explanations, predictions, and evidence.
  • Compare a simplified classroom sequence with inquiry in practice.
  • Credit a source and explain an idea in original words.

Prerequisite: scientific method notes. Materials: paper or a document editor and access to the two readings below. The teacher should open the readings before assigning them; a printed excerpt selected under the source’s terms or a teacher explanation can replace web access.

Reading stations

  1. OpenStax: The Process of Science. Find how the reading distinguishes a hypothesis from a prediction and how evidence is used to examine an explanation.
  2. College Board: AP Biology Lab Manual Resource Center. Read the overview of inquiry-based investigations. Identify examples of decisions students can make about methods, measurements, or analysis. This is a source about teaching inquiry, not a required procedure for this activity.

Student response sheet

Record the title, organization, URL, and date accessed for each reading. In your own words, answer:

  1. What makes a question investigable with scientific evidence?
  2. How does a prediction differ from a proposed explanation?
  3. Why might a researcher return to an earlier question or revise a method?
  4. What useful role does a classroom sequence play? What does it leave out?
  5. How could observations contribute to an investigation without a manipulated treatment?

Apply what you learned

Plan a paper investigation of how water availability might affect seed germination. Define “germinated,” the measurement period, treatment levels, independent experimental units, conditions kept comparable, and an appropriate comparison. Explain what pattern would support your prediction and what alternative explanation would still need attention. No seeds, chemicals, or organisms are handled during this web quest.

Teacher feedback

A useful plan names observable outcomes and avoids treating “better growth” as a measurement. If seeds share a container, students should consider whether the container rather than each seed is the independently treated unit. A good response credits sources, distinguishes the two readings’ purposes, and acknowledges uncertainty. Do not require an “if–then” sentence as the only acceptable form of a scientific hypothesis.

Assessment: check accurate concepts, specific design choices, reasons for those choices, and source credit. For AP extension, ask students to identify a confound and propose a better sampling or treatment-assignment strategy.

Related teaching resources

Sources and further reading