About 25 of the 92 natural elements are known to be essential to
life. Which four of these 25 elements make up approximately 96% of
living matter?
A) carbon, sodium, hydrogen, nitrogen
B)
carbon, oxygen, phosphorus, hydrogen
C) oxygen, hydrogen,
calcium, nitrogen
D) carbon, hydrogen, nitrogen, oxygen
E)
carbon, oxygen, nitrogen, calcium
Answer: D
2
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, but not by other organisms such as
bacteria or plants?
A) nitrogen
B) calcium
C) iodine
D) sodium
E) phosphorus
Answer: C
3
Which of the following statements is false?
A) Carbon,
hydrogen, oxygen, and nitrogen are the most abundant elements of
living matter.
B) Some trace elements are very abundant on
Earth.
C) Virtually all organisms require the same elements in
the same quantities.
D) Iron is an example of an element needed
by all organisms.
E) Other than some trace elements, animals are
mostly made up of the same elements as plants, in similar proportions.
Answer: C
4
What factors are most important in determining which elements are
most common in living matter?
A) the relative abundances of the
elements in Earth's crust and atmosphere
B) the emergent
properties of the simple compounds made from these elements
C)
the reactivity of the elements with water
D) the chemical
stability of the elements
E) both the relative abundances of the
elements and the emergent properties of the compounds made from these elements
Answer: E
5
Why is each element unique and different from other elements in
chemical properties?
A) Each element has a unique atomic mass.
B) Each element has a unique atomic weight.
C) Each
element has a unique number of protons in its nucleus.
D) Each
element has a unique number of neutrons in its nucleus.
E) Each
element has different radioactive properties.
Answer: C
6
Knowing just the atomic mass of an element allows inferences about
which of the following?
A) the chemical properties of the
element
B) the number of protons in the element
C) the
number of neutrons in the element
D) the number of protons plus
neutrons in the element
E) both the number of protons and the
chemical properties of the element
Answer: D
7
In what way are elements in the same column of the periodic table
the same?
A) They have the same number of protons.
B) They
have the same number of neutrons.
C) They have the same number
of electrons.
D) They have the same number of electrons in their
valence shell.
E) They have the same number of electron shells.
Answer: D
8
Oxygen has an atomic number of 8 and a mass number of 16. Thus,
what is the atomic mass of an oxygen atom?
A) exactly 8 grams
B) exactly 8 daltons
C) approximately 16 grams
D)
approximately 16 daltons
E) 24 amu (atomic mass units)
Answer: D
9
) 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 and an
atomic number of 14.
E) The nitrogen atom has a mass number of
14 and an atomic mass of approximately 14 daltons.
Answer: E
10
Molybdenum has an atomic number of 42. Several common isotopes
exist, with mass numbers of 92, 94, 95, 96, 97, 98, and 100.
Therefore, which of the following can be true?
A) Molybdenum
atoms can have between 50 and 58 neutrons.
B) The isotopes of
molybdenum have different electron configurations.
C) The
isotopes of molybdenum can have between 50 and 58 protons.
D)
The isotopes of molybdenum have between 50 and 58 neutrons and have
different electron configurations.
E) The isotopes of molybdenum
have between 50 and 58 protons and have different electron configurations.
Answer: A
11
Carbon-12 is the most common isotope of carbon, and has an atomic
mass of 12 daltons. A mole of carbon in naturally occurring coal,
however, weighs slightly more than 12 grams. Why?
A) The atomic
mass does not include the mass of electrons.
B) Some carbon
atoms in nature have an extra proton.
C) Some carbon atoms in
nature have more neutrons.
D) Some carbon atoms in nature have a
different valence electron distribution.
E) Some carbon atoms in
nature have undergone radioactive decay.
Answer: C
12
Which of the following best describes the relationship between the
atoms described below? [SEE IMAGE]
A) They are isomers.
B)
They are polymers.
C) They are isotopes.
D) They contain 1
and 3 protons, respectively.
E) They each contain 1 neutron.
Answer: C
13
The precise weight of a mole of some pure elements like silicon
(Si) can vary slightly from the standard atomic mass, or even from
sample to sample. Why?
A) The element may undergo radioactive
decay.
B) The element may react with itself and gain or lose
subatomic particles.
C) The atoms of the element form chemical
bonds with each other, and that changes the weight of the element.
D) The element may have multiple stable isotopes, and the
isotopic composition may vary from sample to sample.
E) The
amount of energy absorbed by the element affects the mass of its
electrons, and thus the atomic mass can vary slightly.
Answer: D
14
One difference between carbon-12 (12/6 C) is that carbon-14 (14/6
C) has
A) two more protons than carbon-12.
B) two more
electrons than carbon-12.
C) two more neutrons than carbon-12.
D) two more protons and two more neutrons than carbon-12.
E) two more electrons and two more neutrons than carbon-12.
Answer: C
15
An atom has 6 electrons in its outer shell. How many unpaired
electrons does it have?
A) 0
B) 2
C) 4
D) 6
E) 2 or 4
Answer: B
16
The atomic number of nitrogen is 7. Nitrogen-15 is heavier than
nitrogen-14 because the atomic nucleus of nitrogen-15 contains how
many neutrons?
A) 6
B) 7
C) 8
D) 12
E) 14
Answer: C
17
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 away 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,
and become a radioactive isotope.
E) the atom would become a
negatively charged ion, or anion.
Answer: A
18
The atomic number of neon is 10. Therefore, which of the following
is most 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) It has 8 electrons in its outer
electron shell and it is inert.
E) It has 8 electrons in its
outer electron shell, it is inert, and it has an atomic mass of 10 daltons.
Answer: D
19
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) 15 protons and 15 electrons.
Answer: E
20
Atoms whose outer electron shells contain 8 electrons tend
to
A) form ions in aqueous solutions.
B) form hydrogen
bonds in aqueous solutions.
C) be stable and chemically
nonreactive, or inert.
D) be gaseous at room temperature.
E) be both chemically inert and gaseous at room temperature.
Answer: E
21
The atomic number of each atom is given to the left of each of the
elements below. Which of the atoms has the same valence as carbon
(12/6 C)?
A) ₇N nitrogen
B) ₉F flourine
C) ₁₀Ne neon
D) ₁₂Mg magnesium
E) ₁₄Si silicon
Answer: E
22
Two atoms appear to have the same mass number. These atoms
A)
must have the same atomic number.
B) must have the same number
of electrons.
C) must have the same chemical properties.
D) must have the same number of protons + neutrons.
E)
must have the same atomic number, the same number of protons +
neutrons, the same number of electrons, and the same chemical properties.
Answer: D
23
Fluorine has an atomic number of 9 and a mass number of 19. How
many electrons are needed to complete the valence shell of a
fluorine atom?
A) 1
B) 3
C) 0
D) 7
E) 9
Answer: A
24
24) What is the maximum number of electrons in a single 2 p orbital of an atom?
Chapter 2
In a single molecule of water, two hydrogen atoms are bonded to a
single oxygen atom by
A) hydrogen bonds.
B) nonpolar
covalent bonds.
C) polar covalent bonds.
D) ionic bonds.
E) van der Waals interactions.
Answer: C
2
The slight negative charge at one end of one water molecule is
attracted to the slight positive charge of another water molecule.
What is this attraction called?
A) a covalent bond
B) a
hydrogen bond
C) an ionic bond
D) a hydrophilic bond
E) a van der Waals interaction
Answer: B
3
The partial negative charge in a molecule of water occurs because
A) the oxygen atom acquires an additional electron.
B) the
electrons shared between the oxygen and hydrogen atoms spend more time
around the oxygen atom nucleus than around the hydrogen atom nucleus.
C) the oxygen atom has two pairs of electrons in its valence
shell that are not neutralized by hydrogen atoms.
D) the oxygen
atom forms hybrid orbitals that distribute electrons unequally around
the oxygen nucleus.
E) one of the hydrogen atoms donates an
electron to the oxygen atom.
Answer: B
4
Sulfur is in the same column of the periodic table as oxygen, but
has electronegativity similar to carbon. Compared to water molecules,
molecules of H₂S
A) will ionize more readily.
B) will have
greater cohesion to other molecules of H₂S.
C) will have a
greater tendency to form hydrogen bonds with each other.
D) will
have a higher capacity to absorb heat for the same change in
temperature.
E) will not form hydrogen bonds with each other.
Answer: E
5
Water molecules are able to form hydrogen bonds with
A)
compounds that have polar covalent bonds.
B) oils.
C)
oxygen gas (O₂) molecules.
D) chloride ions.
E) any
compound that is not soluble in water.
Answer: A
6
Which of the following effects is produced by the high surface
tension of water?
A) Lakes don't freeze solid in winter, despite
low temperatures.
B) A water strider can walk across the surface
of a small pond.
C) Organisms resist temperature changes,
although they give off heat due to chemical reactions.
D)
Evaporation of sweat from the skin helps to keep people from
overheating.
E) Water flows upward from the roots to the leaves
in plants.
Answer: B
7
Which of the following takes place as an ice cube cools a drink?
A) Molecular collisions in the drink increase.
B) Kinetic
energy in the drink decreases.
C) A calorie of heat energy is
transferred from the ice to the water of the drink.
D) The
specific heat of the water in the drink decreases.
E)
Evaporation of the water in the drink increases.
Answer: B
8
A dietary Calorie equals 1 kilocalorie. Which of the following
statements correctly defines 1 kilocalorie?
A) 1,000 calories,
or the amount of heat required to raise the temperature of 1 g of
water by 1,000°C
B) 100 calories, or the amount of heat required
to raise the temperature of 100 g of water by 1°C
C) 10,000
calories, or the amount of heat required to raise the temperature of 1
kg of water by 1°F
D) 1,000 calories, or the amount of heat
required to raise the temperature of 1 kg of water by 1°C
E)
1,000 calories, or the amount of heat required to raise the
temperature of 100 g of water by 100°C
Answer: D
9
The nutritional information on a cereal box shows that one serving
of a dry cereal has 200 kilocalories. If one were to burn one serving
of the cereal, the amount of heat given off would be sufficient to
raise the temperature of 20 kg of water how many degrees Celsius?
A) 0.2°C
B) 1.0°C
C) 2.0°C
D) 10.0°C
E) 20.0°C
Answer: D
10
Liquid water's high specific heat is mainly a consequence of the
A) small size of the water molecules.
B) high specific
heat of oxygen and hydrogen atoms.
C) absorption and release of
heat when hydrogen bonds break and form.
D) fact that water is a
poor heat conductor.
E) higher density of liquid water than
solid water (ice).
Answer: C
11
Which type of bond must be broken for water to vaporize?
A)
ionic bonds
B) both hydrogen bonds and ionic bonds
C)
polar covalent bonds
D) hydrogen bonds
E) both polar
covalent bonds and hydrogen bonds
Answer: D
12
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
Answer: C
13
Why does evaporation of water from a surface cause cooling of the
surface?
A) The breaking of bonds between water molecules
absorbs heat.
B) The water molecules with the most heat energy
evaporate more readily.
C) The solute molecules left behind
absorb heat.
D) Water molecules absorb heat from the surface in
order to acquire enough energy to evaporate.
E) The expansion of
water vapor extracts heat from the surface.
Answer: B
14
Why does ice float in liquid water?
A) The high surface
tension of liquid water keeps the ice on top.
B) The ionic bonds
between the molecules in ice prevent the ice from sinking.
C)
Ice always has air bubbles that keep it afloat.
D) Hydrogen
bonds stabilize and keep the molecules of ice farther apart than the
water molecules of liquid water.
E) The crystalline lattice of
ice causes it to be denser than liquid water.
Answer: D
15
Hydrophobic substances such as vegetable oil are
A) nonpolar
substances that repel water molecules.
B) nonpolar substances
that have an attraction for water molecules.
C) polar substances
that repel water molecules.
D) polar substances that have an
affinity for water.
E) charged molecules that hydrogen-bond with
water molecules.
Answer: A
16
One mole (mol) of glucose (molecular mass = 180 daltons) is
A) 180 × 10²³ molecules of glucose.
B) 1 kg of glucose
dissolved in 1 L of solution.
C) the largest amount of glucose
that can be dissolved in 1 L of solution.
D) 180 kilograms of
glucose.
E) both 180 grams of glucose and 6.02 × 10²³
molecules of glucose.
Answer: E
17
How many molecules of glucose (C₆H₁₂O₆ molecular mass = 180
daltons) would be present in 90 grams of glucose?
A) 90 × 10²³
B) (6.02/180) × 10²³
C) (6.02/90) × 10²³
D) (90 x
6.02) × 10²³
E) (90/180) × 6.02 × 10²³
Answer: E
18
How many molecules of glycerol (C₃H₈O₃; molecular mass = 92) would
be present in 1 L of a 1 M glycerol solution?
A) 1 × 10⁶
B) 14 × 6.02 × 10²³
C) 92 × 6.02 × 10²³
D) 6.02 ×
10²⁶
E) 6.02 × 10²³
Answer: E
19
When an ionic compound such as sodium chloride (NaCl) is placed in
water, the component atoms of the NaCl crystal dissociate into
individual sodium ions (Na⁺) and chloride ions (Cl⁻). In contrast, the
atoms of covalently bonded molecules (e.g., glucose, sucrose,
glycerol) do not generally dissociate when placed in aqueous solution.
Which of the following solutions would be expected to contain the
greatest number of solute particles (molecules or ions)?
A) 1 L
of 0.5 M NaCl
B) 1 L of 0.5 M glucose
C) 1 L of 1.0 M NaCl
D) 1 L of 1.0 M glucose
E) 1 L of 1.0 M NaCl and 1 L of
1.0 M glucose will contain equal numbers of solute particles.
Answer: C
20
The molar mass of glucose is 180 g/mol. Which of the following
procedures should you carry out to make a 1 M solution of glucose?
A) Dissolve 1 g of glucose in 1 L of water.
B) Dissolve
180 g of glucose in 1 L of water.
C) Dissolve 180 g of glucose
in 180 g of water.
D) Dissolve 180 milligrams (mg) of glucose in
1 L of water.
E) Dissolve 180 g of glucose in 0.8 L of water,
and then add more water until the total volume of the solution is 1 L.
Answer: E
21
The molar mass of glucose (C₆H₁₂O₆) is 180 g/mol. Which of the
following procedures should you carry out to make a 0.5 M solution of
glucose?
A) Dissolve 0.5 g of glucose in a small volume of
water, and then add more water until the total volume of solution is 1
L.
B) Dissolve 90 g of glucose in a small volume of water, and
then add more water until the total volume of the solution is 1 L.
C) Dissolve 180 g of glucose in a small volume of water, and
then add more water until the total volume of the solution is 1 L.
D) Dissolve 0.5 g of glucose in 1 L of water.
E) Dissolve
180 g of glucose in 0.5 L of water.
Answer: B
22
You have a freshly prepared 0.1 M solution of glucose in water.
Each liter of this solution contains how many glucose molecules?
A) 6.02 × 10²³
B) 3.01 × 10²³
C) 6.02 × 10²⁴
D) 12.04 × 10²³
E) 6.02 × 10²²
Answer: E
Chapter 3
When biologists wish to study the internal ultrastructure of cells,
they can achieve the finest resolution by using
A) a
phase-contrast light microscope.
B) a scanning electron
microscope.
C) a transmission electronic microscope.
D) a
confocal fluorescence microscope.
E) a super-resolution
fluorescence microscope.
Answer: C
2
The advantage of light microscopy over electron microscopy is that
A) light microscopy provides for higher magnification than
electron microscopy.
B) light microscopy provides for higher
resolving power than electron microscopy.
C) light microscopy
allows one to view dynamic processes in living cells.
D) light
microscopy provides higher contrast than electron microscopy.
E)
specimen preparation for light microcopy does not produce artifacts.
Answer: C
3
A primary objective of cell fractionation is to
A) view the
structure of cell membranes.
B) sort cells based on their size
and weight.
C) determine the size of various organelles.
D) separate the major organelles so that their particular
functions can be determined.
E) separate lipid-soluble from
water-soluble molecules.
Answer: D
4
In the fractionation of homogenized cells using centrifugation, the
primary factor that determines whether a specific cellular component
ends up in the supernatant or the pellet is
A) the relative
solubility of the component.
B) the size and weight of the
component.
C) the percentage of carbohydrates in the component.
D) the presence or absence of nucleic acids in the component.
E) the presence or absence of lipids in the component.
Answer: B
5
Which of the following correctly lists the order in which cellular
components will be found in the pellet when homogenized cells are
treated with increasingly rapid spins in a centrifuge?
A)
ribosomes, nucleus, mitochondria
B) chloroplasts, ribosomes,
vacuoles
C) nucleus, ribosomes, chloroplasts
D) vacuoles,
ribosomes, nucleus
E) nucleus, mitochondria, ribosomes
Answer: E
6
Green fluorescent protein (GFP) can be used to fluorescently label
a specific protein in cells by genetically engineering cells to
synthesize the target protein fused to GFP. What is the advantage of
using GFP fusions to visualize specific proteins, instead of staining
cells with fluorescently labeled probes that bind to the target
protein?
A) GFP fusions enable one to track changes in the
location of the protein in living cells; staining usually requires
preserved cells.
B) GFP fusions enable higher resolution than
staining with fluorescent probes.
C) GFP permits the position of
the protein in the cell more precisely than fluorescent probes.
D) GFP permits visualization of protein-protein interactions;
fluorescent probes do not.
E) GFP fusions are not subject to
artifacts; fluorescent probes may introduce background artifacts.
Answer: A
7
What is the reason that a modern electron microscope (TEM) can
resolve biological images to the subnanometer level, as opposed to
tens of nanometers achievable for the best super-resolution light
microscope?
A) The focal length of the electron microscope is
significantly longer.
B) Contrast is enhanced by staining with
atoms of heavy metal.
C) Electron beams have much shorter
wavelengths than visible light.
D) The electron microscope has a
much greater ratio of image size to real size.
E) The electron
microscope cannot image whole cells at one time.
Answer: C
8
What technique would be most appropriate to use to observe the
movements of condensed chromosomes during cell division?
A)
light microscopy
B) scanning electron microscopy
C)
transmission electron microscopy
D) confocal fluorescence
microscopy
E) super-resolution fluorescence microscopy
Answer: A
9
All of the following are part of a prokaryotic cell except
A)
DNA.
B) a cell wall.
C) a plasma membrane.
D)
ribosomes.
E) an endoplasmic reticulum.
Answer: E
10
The volume enclosed by the plasma membrane of plant cells is often
much larger than the corresponding volume in animal cells. The most
reasonable explanation for this observation is that
A) plant
cells are capable of having a much higher surface-to-volume ratio than
animal cells.
B) plant cells have a much more highly convoluted
(folded) plasma membrane than animal cells.
C) plant cells
contain a large vacuole that reduces the volume of the cytoplasm.
D) animal cells are more spherical, whereas plant cells are
elongated.
E) plant cells can have lower surface-to-volume
ratios than animal cells because plant cells synthesize their own nutrients.
Answer: C
11
A mycoplasma is an organism with a diameter between 0.1 and 1.0 µm.
What does the organism's size tell you about how it might be
classified?
A) It must be a single-celled protist.
B) It
must be a single-celled fungus.
C) It could be almost any
typical bacterium.
D) It could be a typical virus.
E) It
could be a very small bacterium.
Answer: E
12
Which of the following is a major cause of the size limits for
certain types of cells?
A) limitation on the strength and
integrity of the plasma membrane as cell size increases
B) the
difference in plasma membranes between prokaryotes and eukaryotes
C) evolutionary progression in cell size; more primitive cells
have smaller sizes
D) the need for a surface area of sufficient
area to support the cell's metabolic needs
E) rigid cell walls
that limit cell size expansion
Answer: D
13
Which of the following statements concerning bacteria and archaea
cells is correct?
A) Archaea cells contain small
membrane-enclosed organelles; bacteria do not.
B) Archaea cells
contain a membrane-bound nucleus; bacteria do not.
C) DNA is
present in both archaea cells and bacteria cells.
D) DNA is
present in the mitochondria of both bacteria and archaea cells.
Answer: A
14
The evolution of eukaryotic cells most likely involved
A)
endosymbiosis of an aerobic bacterium in a larger host cell–the
endosymbiont evolved into mitochondria.
B) anaerobic archaea
taking up residence inside a larger bacterial host cell to escape
toxic oxygen–the anaerobic bacterium evolved into chloroplasts.
C) an endosymbiotic fungal cell evolved into the nucleus.
D) acquisition of an endomembrane system, and subsequent
evolution of mitochondria from a portion of the Golgi.
Answer: A
15
Prokaryotes are classified as belonging to two different domains.
What are the domains?
A) Bacteria and Eukarya
B) Bacteria
and Archaea
C) Archaea and Protista
D) Bacteria and
Protista
E) Bacteria and Fungi
Answer: B
16
If radioactive deoxythymidine triphosphate (dTTP) is added to a
culture of rapidly growing bacterial cells, where in the cell would
you expect to find the greatest concentration of radioactivity?
A) nucleus
B) cytoplasm
C) endoplasmic reticulum
D) nucleoid
E) ribosomes
Answer: D
17
Which organelle or structure is absent in plant cells?
A)
mitochondria
B) Golgi vesicles
C) microtubules
D)
centrosomes
E) peroxisomes
Answer: D
18
Large numbers of ribosomes are present in cells that specialize in
producing which of the following molecules?
A) lipids
B)
glycogen
C) proteins
D) cellulose
E) nucleic acids
Answer: C
19
The nuclear lamina is an array of filaments on the inner side of
the nuclear membrane. If a method were found that could cause the
lamina to fall into disarray, what would you expect to be the most
likely consequence?
A) the loss of all nuclear function
B) the inability of the nucleus to divide during cell division
C) a change in the shape of the nucleus
D) failure of
chromosomes to carry genetic information
E) inability of the
nucleus to keep out destructive chemicals
Answer: C
20
Recent evidence shows that when chromosomes decondense during
interphase, their DNA molecules do not intermingle. Instead, they
occupy distinct territories within the nucleus. Considering the
structure and location of the following structures, which is most
likely to be involved in chromosome location?
A) nuclear pores
B) the nucleolus
C) microfilaments
D) the nuclear
lamina
E) the nuclear matrix
Answer: E
21
A cell with a predominance of free ribosomes is most likely
A) producing primarily proteins for secretion.
B)
producing primarily cytoplasmic proteins.
C) constructing an
extensive cell wall or extracellular matrix.
D) digesting
large food particles.
E) enlarging its vacuole.
Answer: B
22
Which type of organelle or structure is primarily involved in the
synthesis of oils, phospholipids, and steroids?
A) ribosome
B) lysosome
C) smooth endoplasmic reticulum
D)
mitochondrion
Chapter 6