AP Biology Test Midterm 1
Multiple Choice
Identify the letter of the choice that best completes the statement or answers the question.
1. 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, chlorine, nitrogen
B)
carbon, sulfur, phosphorus, hydrogen
C)
oxygen, hydrogen, calcium, sodium
D)
carbon, hydrogen, nitrogen, oxygen
E)
carbon, oxygen, sulfur, calcium
2. Different atomic forms of an element contain the same number of protons but a different number of neutrons. What
are these different atomic forms called?
A)
ions
B)
isotopes
C)
neutronic atoms
D)
isomers
E)
radioactive atoms
3. What do atoms form when they share electron pairs?
A)
elements
B)
ions
C)
aggregates
D)
isotopes
E)
molecules
4. A covalent bond is likely to be polar when
A)
B)
C)
D)
E)
5. A polar covalent bond can form when
A)
B)
C)
D)
E)
one of the atoms sharing electrons is much more
electronegative than the other atom.
the two atoms sharing electrons are equally electronegative.
the two atoms sharing electrons are of the same element.
it is between two atoms that are both very strong electron
acceptors.
the two atoms sharing electrons are different elements.
there is the loss of one or more electrons from one atom to
another atom of the same molecule.
there is the gain of one or more electrons from one atom to
another atom of the same molecule.
one of the atoms has a greater affinity for electrons than the
other atom of the same molecule.
one of the atoms has a greater affinity for neutrons than the
other atom of the same molecule.
two atoms of a molecule attract electrons equally.
6. Which of the following molecules contains the strongest polar covalent bond?
A)
H2
B)
O2
C)
CO2
D)
H2O
E)
CH4
7. The ionic bond of sodium chloride is formed when
A)
chlorine gains an electron from sodium.
B)
sodium and chlorine share an electron pair.
C)
sodium and chlorine both lose electrons from their outer
valence shells.
D)
sodium gains an electron from chlorine.
E)
chlorine gains a proton from sodium.
8. What is the difference between covalent bonds and ionic bonds?
A)
Covalent bonds involve the sharing of protons between atoms,
and ionic bonds involve the sharing of electrons between
atoms.
B)
Covalent bonds involve the sharing of neutrons between atoms,
and ionic bonds involve the sharing of electrons between
atoms.
C)
Covalent bonds involve the sharing of electrons between atoms,
and ionic bonds involve the electrical attraction between atoms.
D)
Covalent bonds involve the sharing of protons between atoms,
and ionic bonds involve the sharing of neutrons between atoms.
E)
Covalent bonds involve the transfer of electrons between
atoms, and ionic bonds involve the sharing of neutrons between
atoms.
9. Explains most specifically the attraction of water molecules to one another.
A)
nonpolar covalent bond
B)
polar covalent bond
C)
ionic bond
D)
hydrogen bond
E)
hydrophobic interaction
10. Water is able to form hydrogen bonds because
A)
B)
C)
oxygen has a valence of 2.
the water molecule is shaped like a tetrahedron.
the bonds that hold together the atoms in a water molecule are
polar covalent bonds.
D)
the oxygen atom in a water molecule has a weak positive
charge.
E)
each of the hydrogen atoms in a water molecule is weakly
negative in charge.
11. What determines the cohesiveness of water molecules?
A)
hydrophobic interactions
B)
nonpolar covalent bonds
C)
D)
E)
ionic bonds
hydrogen bonds
both A and C
12. Which of the following is possible due to 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)
Water can act as a solvent.
E)
The pH of water remains exactly neutral.
13. 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.
14. Which of the following solutions has the greatest concentration of hydrogen ions [H+]?
A)
gastric juice at pH 2
B)
vinegar at pH 3
C)
tomato juice at pH 4
D)
black coffee at pH 5
E)
household bleach at pH 12
15. Which of the following is not one of the four major groups of macromolecules found in living organisms?
A)
glucose
B)
carbohydrates
C)
lipids
D)
proteins
E)
nucleic acids
16. A molecule with the chemical formula C16H32O16 is probably a
A)
carbohydrate.
B)
lipid.
C)
protein.
D)
nucleic acid.
E)
hydrocarbon.
17. A polypeptide can best be described as a
A)
B)
C)
D)
E)
monomer of a protein polymer.
polymer containing 20 amino acid molecules.
polymer containing 19 peptide bonds.
polymer containing 20 peptide bonds.
polymer of amino acids.
18. Of the following functions, the major purpose of RNA is to
A)
transmit genetic information to offspring.
B)
function in the synthesis of protein.
C)
make a copy of itself, thus ensuring genetic continuity.
D)
act as a pattern or blueprint to form DNA.
E)
form the genes of higher organisms.
19. Which of the following best describes the flow of information in eukaryotic cells?
A)
DNA RNA proteins
B)
RNA proteins DNA
C)
proteins DNA RNA
D)
RNA DNA proteins
E)
DNA proteins RNA
20. Which of the following descriptions best fits the class of molecules known as nucleotides?
A)
a nitrogenous base and a phosphate group
B)
a nitrogenous base and a pentose sugar
C)
a nitrogenous base, a phosphate group, and a pentose sugar
D)
a phosphate group and an adenine or uracil
E)
a pentose sugar and a purine or pyrimidine
21. All of the following nitrogenous bases are found in DNA except
A)
thymine.
B)
adenine.
C)
uracil.
D)
guanine.
E)
cytosine.
22.Which of the following are prokaryotic cells?
A)
B)
C)
D)
E)
plants
fungi
bacteria
animals
B and C only
23. 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.
24. Which of the following comparisons between prokaryotic and eukaryotic cells is incorrect?
A) The lack of organelles in prokaryotes means that they are structurally less complex than eukaryotes.
B) The lack of internal membranes means that prokaryotes cannot compartmentalize function to the same extent as
eukaryotes.
C)All membrane function in prokaryotes is accomplished in the plasma membrane, while in eukaryotes, these
functions are more distributed among the organelles.
D)The specialization of function in organelles suggests that eukaryotes will contain a wider variety of
phospholipids than prokaryotes.
E)The lack of organelles in prokaryotes means that the basic cellular
25. Which of the following organelles is not a common destination for small vesicles that bud off the Golgi apparatus?
A)plasma membrane
B)lysosomes
C)vacuole
D)endoplasmic reticulum
E)all of the above
26. Which structure is the site of the synthesis of proteins that may be exported from the cell?
A)rough ER
B) lysosomes
C)plasmodesmata
D)Golgi vesicles
E)tight junctions
27. All of the following molecules are part of the cell membrane except
A)lipids.
B)nucleic acids.
C)proteins.
D)phosphate groups.
E)steroids.
28. According to the fluid mosaic model of cell membranes, which of the following is a true statement about
membrane phospholipids?
A)They can move laterally along the plane of the membrane.
B)They frequently flip-flop from one side of the membrane to the other.
C)They occur in an uninterrupted bilayer, with membrane proteins restricted to the surface of the membrane.
D)They are free to depart from the membrane and dissolve in the surrounding solution.
E) They have hydrophilic tails in the interior of the membrane.
29. Of the following functions, which is most important for the glycoproteins and glycolipids of animal cell
membranes?
A)facilitated diffusion of molecules down their concentration gradients
B)active transport of molecules against their concentration gradients
C)maintaining the integrity of a fluid mosaic membrane
D)maintaining membrane fluidity at low temperatures
E) a cell's ability to distinguish one type of neighboring cell from another
30. What kinds of molecules pass through a cell membrane most easily?
A)large and hydrophobic
B)small and hydrophobic
C)large polar
D)ionic
E)monosaccharides such as glucose
31. Which of the following would likely move through the lipid bilayer of a plasma membrane most rapidly?
A)CO2
B)an amino acid
C)glucose
D)K+
E)starch
32.Which of the following statements is correct about diffusion?
A)It is very rapid over long distances.
B)It requires an expenditure of energy by the cell.
C)It is a passive process in which molecules move from a region of higher concentration to a region of lower
concentration.
D)It is an active process in which molecules move from a region of lower concentration to one of higher
concentration.
E)It requires integral proteins in the cell membrane.
33. Celery stalks that are immersed in fresh water for several hours become stiff and hard. Similar stalks left in a salt
solution become limp and soft. From this we can deduce that the cells of the celery stalks are
A)hypotonic to both fresh water and the salt solution.
B)hypertonic to both fresh water and the salt solution.
C)hypertonic to fresh water but hypotonic to the salt solution.
D)hypotonic to fresh water but hypertonic to the salt solution.
E)isotonic with fresh water but hypotonic to the salt solution.
34. The main difference(s) between facilitated diffusion and active transport is (are)
A)facilitated diffusion moves substances down their concentration gradient and active transport moves them
against their gradient.
B)facilitated diffusion does not rely on cellular energy and active transport does.
C)facilitated diffusion uses channel or carrier proteins and active transport does not.
D)A and B only
E) A, B, and C
35. Which term most precisely describes the cellular process of breaking down large molecules into smaller ones?
A)
catalysis
B)
metabolism
C)
anabolism
D)
dehydration
E)
catabolism
36. Which of the following statements correctly describe(s) catabolic pathways?
A)They do not depend on enzymes.
B)They consume energy to build up polymers from monomers.
C)They release energy as they degrade polymers to monomers.
D)They lead to the synthesis of catabolic compounds.
E)both A and B
37. What is the term used for the metabolic pathway in which glucose (C6H12O6) is degraded to carbon dioxide (CO2)
and water?
A)cellular respiration
B)glycolysis
C)fermentation
D)citric acid cycle
E)oxidative phosphorylation
38. Which of the following statements describes the results of this reaction?
C6H12O6 + 6 O2 6 CO2 + 6 H2O + Energy
A)
C6H12O6 is oxidized and O2 is reduced.
B)
O2 is oxidized and H2O is reduced.
C)
CO2 is reduced and O2 is oxidized.
D)
C6H12O6is reduced and CO2 is oxidized.
E)
O2 is reduced and CO2 is oxidized.
39. Where does glycolysis takes place?
A)
B)
C)
D)
E)
40. The ATP made during glycolysis is generated by
A)substrate-level phosphorylation.
B)electron transport.
C)photophosphorylation.
D)chemiosmosis.
E)oxidation of NADH to NAD+.
mitochondrial matrix
mitochondrial outer membrane
mitochondrial inner membrane
mitochondrial intermembrane space
cytosol
41. The oxygen consumed during cellular respiration is involved directly in which process or event?
A)glycolysis
B)accepting electrons at the end of the electron transport chain
C)the citric acid cycle
D)the oxidation of pyruvate to acetyl CoA
E)the phosphorylation of ADP to form ATP
42. During glycolysis, when glucose is catabolized to pyruvate, most of the energy of glucose is
A)
transferred to ADP, forming ATP.
B)
transferred directly to ATP.
C)
retained in the pyruvate.
D)
stored in the NADH produced.
E)
used to phosphorylate fructose to form fructose-6-phosphate.
43. In addition to ATP, what are the end products of glycolysis?
A)CO2 and H2O
B)CO2 and pyruvate
C)NADH and pyruvate
D)CO2 and NADH
E)H2O, FADH2, and citrate
44. A young relative of yours has never had much energy. He goes to a doctor for help and is sent to the hospital for
some tests. There they discover his mitochondria can use only fatty acids and amino acids for respiration, and his
cells produce more lactate than normal. Of the following, which is the best explanation of his condition?
A)His mitochondria lack the transport protein that moves pyruvate across the outer mitochondrial membrane.
B)His cells cannot move NADH from glycolysis into the mitochondria.
C)His cells contain something that inhibits oxygen use in his mitochondria.
D)His cells lack the enzyme in glycolysis that forms pyruvate.
E)His cells have a defective electron transport chain, so glucose goes to lactate instead of to acetyl CoA.
45. Cellular respiration harvests the most chemical energy from which of the following?
A)substrate-level phosphorylation
B)chemiosmotic phosphorylation
C)converting oxygen to ATP
D)transferring electrons from organic molecules to pyruvate
E)generating carbon dioxide and oxygen in the electron transport chain
46. The primary role of oxygen in cellular respiration is to
A)
yield energy in the form of ATP as it is passed down the
respiratory chain.
B)
act as an acceptor for electrons and hydrogen, forming water.
C)
combine with carbon, forming CO2.
D)
combine with lactate, forming pyruvate.
E)
catalyze the reactions of glycolysis.
47. Inside an active mitochondrion, most electrons follow which pathway?
A)
glycolysis NADH oxidative phosphorylation ATP oxygen
B)
citric acid cycle FADH2 electron transport chain ATP
C)
electron transport chain citric acid cycle ATP oxygen
D)
pyruvate citric acid cycle ATP NADH oxygen
E)
citric acid cycle NADH electron transport chain oxygen
48. Organisms that can exist with light as an energy source and an inorganic form of carbon and other raw materials
A)
are called photoautotrophs.
B)
do not exist in nature.
C)
are called heterotrophs.
D)
are best classified as decomposers.
E)
both C and D
49. Which type of organism obtains energy by metabolizing molecules produced by other organisms?
A)autotrophs
B)heterotrophs
C)decomposers
D)B and C
E)A, B, and C
50.Which of the following are products of the light reactions of photosynthesis that are utilized in the Calvin cycle?
A)
CO2 and glucose
B)
H2O and O2
C)
ADP, Pi, and NADP+
D)
electrons and H+
E)
ATP and NADPH
51. What is the primary function of the light reactions of photosynthesis?
A)
to produce energy-rich glucose from carbon dioxide and water
B)
to produce ATP and NADPH
C)
to produce NADPH used in respiration
D)
to convert light energy to the chemical energy of PGAL
E)
to use ATP to make glucose
52.Which of the following statements best describes the relationship between photosynthesis and respiration?
A)
Respiration is the reversal of the biochemical pathways of
photosynthesis.
B)
Photosynthesis stores energy in complex organic molecules,
while respiration releases it.
C)
Photosynthesis occurs only in plants and respiration occurs
only in animals.
D)
ATP molecules are produced in photosynthesis and used up in
respiration.
E)
Respiration is anabolic and photosynthesis is catabolic.