BIO 203 EXAM 1 - PREP FOR FINAL
QUESTIONS & ANSWERS (RATED
A+)
The best experimental design ______.
A) includes a large sample size for each condition
B) includes a control
C) alters only one condition between the controls and the experimental conditions
D) includes a large sample size and a control and alters only one condition between
the controls and the experimental condition - ANSWERD
A solution with a pH of 5 has how many more protons in it than a solution with a pH
of 7?
A) 5 times
B) 10 times
C) 100 times
D) 1000 times - ANSWERC
Consider the HIV enzyme called protease. The amino acid residues at the active site
are highly hydrophobic. In designing a drug that would bind to the active site and jam
it, researchers should use a molecule that is ________.
A) hydrophobic
B) polar
C) charged
D) acidic - ANSWERA
Enzymes that break down DNA catalyze the hydrolysis of the covalent bonds that
join nucleotides together. What would happen to DNA molecules treated with these
enzymes?
A) the phosphodiester linkages of the polynucleotide backbone would be broken
B) the two strands of the double helix would separate
C) the purines would be separated from the deoxyribose sugars
D) all bases would be separated from the deoxyribose sugars - ANSWERA
which statement is TRUE for the model shown to the right:
A) this is a monomer of RNA
B) this is a monomer of DNA
C) the sugar in this molecule contains four carbons
D) the nitrogenous base is guanine - ANSWERA
, Which of the following best describes the tertiary structure of RNA molecules, such
as ribozymes?
A) a double-stranded helix
B) a single nucleotide strand folded on itself in a "stem and loop" structure
C) the sequence AUUGCUUC
D) a single nucleotide strand where multiple stem and loop structures begin to
interact - ANSWERD
Which of the following statements is TRUE about enzyme-catalyzed reactions?
A) The reaction is faster than the same reaction in the absence of the enzyme.
B) The free-energy change of the reaction is opposite from the reaction that occurs
in the absence of the enzyme.
C) An enzyme catalyzes a reaction by raising the activation energy.
D) Enzyme-catalyzed reactions require energy to activate the enzyme. - ANSWERA
The partial negative charge at one end of a water molecule is attracted to the partial
positive charge of another water molecule. What is this attraction called?
A) a hydrogen bond
B) a covalent bond
C) an ionic bond
D) a can der Waals interaction - ANSWERA
Why are the hydrocarbons insoluble in water?
A) the majority of their bonds are polar covalent carbon-to hydrogen linkages
B) the majority of their bonds are nonpolar covalent carbon-to-hydrogen likages
C) they are hydrophilic
D) they are less dense than water - ANSWERB
Why are polymerization reactions endergonic? Polymerization reactions ________.
A) reduce entropy
B) release heat, making the reactant monomers move faster
C) release energy
D) are at equilibrium - ANSWERA
The chemical reaction illustrated in the accompanying figure ________
A) is a hydrolysis reaction
B) joins two fatty acids together
C) results in a peptide bond
D) links two polymers to form a monomer - ANSWERC
QUESTIONS & ANSWERS (RATED
A+)
The best experimental design ______.
A) includes a large sample size for each condition
B) includes a control
C) alters only one condition between the controls and the experimental conditions
D) includes a large sample size and a control and alters only one condition between
the controls and the experimental condition - ANSWERD
A solution with a pH of 5 has how many more protons in it than a solution with a pH
of 7?
A) 5 times
B) 10 times
C) 100 times
D) 1000 times - ANSWERC
Consider the HIV enzyme called protease. The amino acid residues at the active site
are highly hydrophobic. In designing a drug that would bind to the active site and jam
it, researchers should use a molecule that is ________.
A) hydrophobic
B) polar
C) charged
D) acidic - ANSWERA
Enzymes that break down DNA catalyze the hydrolysis of the covalent bonds that
join nucleotides together. What would happen to DNA molecules treated with these
enzymes?
A) the phosphodiester linkages of the polynucleotide backbone would be broken
B) the two strands of the double helix would separate
C) the purines would be separated from the deoxyribose sugars
D) all bases would be separated from the deoxyribose sugars - ANSWERA
which statement is TRUE for the model shown to the right:
A) this is a monomer of RNA
B) this is a monomer of DNA
C) the sugar in this molecule contains four carbons
D) the nitrogenous base is guanine - ANSWERA
, Which of the following best describes the tertiary structure of RNA molecules, such
as ribozymes?
A) a double-stranded helix
B) a single nucleotide strand folded on itself in a "stem and loop" structure
C) the sequence AUUGCUUC
D) a single nucleotide strand where multiple stem and loop structures begin to
interact - ANSWERD
Which of the following statements is TRUE about enzyme-catalyzed reactions?
A) The reaction is faster than the same reaction in the absence of the enzyme.
B) The free-energy change of the reaction is opposite from the reaction that occurs
in the absence of the enzyme.
C) An enzyme catalyzes a reaction by raising the activation energy.
D) Enzyme-catalyzed reactions require energy to activate the enzyme. - ANSWERA
The partial negative charge at one end of a water molecule is attracted to the partial
positive charge of another water molecule. What is this attraction called?
A) a hydrogen bond
B) a covalent bond
C) an ionic bond
D) a can der Waals interaction - ANSWERA
Why are the hydrocarbons insoluble in water?
A) the majority of their bonds are polar covalent carbon-to hydrogen linkages
B) the majority of their bonds are nonpolar covalent carbon-to-hydrogen likages
C) they are hydrophilic
D) they are less dense than water - ANSWERB
Why are polymerization reactions endergonic? Polymerization reactions ________.
A) reduce entropy
B) release heat, making the reactant monomers move faster
C) release energy
D) are at equilibrium - ANSWERA
The chemical reaction illustrated in the accompanying figure ________
A) is a hydrolysis reaction
B) joins two fatty acids together
C) results in a peptide bond
D) links two polymers to form a monomer - ANSWERC
