## TITLE('Enzyme Catalytic Strategies and Methods for Lowering Activation Energy')
## DESCRIPTION
## Select the statement that is TRUE or FALSE about Enzyme Catalytic Strategies and Methods for Lowering Activation Energy.
## ENDDESCRIPTION
## KEYWORDS('Enzyme Catalytic Strategies and Methods for Lowering Activation Energy','true/false','multiple choice')
## DBsubject('Biochemistry')
## DBchapter('')
## DBsection('')
## Date('2026-07-12')
## Author('Neil R. Voss')
## Institution('Roosevelt University')
DOCUMENT();
loadMacros(
"PGstandard.pl",
"PGML.pl",
"PGchoicemacros.pl",
"parserRadioButtons.pl",
"PGcourse.pl",
);
TEXT(beginproblem());
$showPartialCorrectAnswers = 1;
#==========================================================
# AUTO-GENERATED GROUPS FROM YAML
#==========================================================
@true_groups = (
[
'Acid-base catalysis involves amino acid side chains donating or accepting protons.',
'Amino acid side chains can participate in proton transfers during catalysis.',
'Amino acid side chains in enzyme active sites often act as proton donors or acceptors.',
],
[
'ATP hydrolysis is used by certain enzymes to drive conformational changes or reaction steps.',
],
[
'Catalysis by approximation involves binding two or more substrates in close proximity.',
'Enzymes enhance catalysis by holding multiple substrates close together and properly aligned.',
'Enzymes increase reaction rates by holding substrates in close proximity and correct orientation.',
'Many enzymes enhance reaction rates by positioning multiple substrates near each other.',
'Orientation of substrate reactive groups by enzyme residues facilitates selective bond formation.',
],
[
'Covalent catalysis involves transient covalent bonds between enzyme and substrate.',
'A transient covalent bond may form between enzyme and substrate to create a reactive intermediate.',
'Covalent bonds between catalytic residues and substrates can form during some reaction mechanisms.',
'In covalent catalysis, the enzyme acts as a temporary electron sink to stabilize intermediates.',
'Nucleophilic residues may form covalent intermediates with the substrate.',
],
[
'Metal ions in the active site stabilize negative charges or mediate redox reactions.',
'Metal ions stabilize negative charges or assist in redox reactions.',
'Electrostatic interactions in the active site can stabilize charged intermediates.',
'In metal ion catalysis, the metal ions can help position water molecules for nucleophilic attack.',
'Positively charged side chains or bound metal ions can stabilize anionic transition states.',
],
[
'Enzymes may use local changes in pH or polarity to provide a favorable active site microenvironment.',
],
[
'Enzymes can distort substrate bonds to resemble the transition state, lowering the activation energy.',
'Enzymes can strain substrate bonds to help lower the activation energy.',
],
);
@false_groups = (
[
'Acid-base catalysis is a mechanism where water is always the proton donor or acceptor.',
'Acid-base catalysis is when an enzyme uses a metal ion to coordinate charges in the active site.',
'Acid-base catalysis requires the active site to be completely nonpolar.',
'Acid-base catalysis requires the substrate to donate a proton to the enzyme.',
'Acid-base catalysis requires the substrate to protonate the enzyme.',
'In acid-base catalysis, the substrate serves as the proton donor to activate the enzyme.',
],
[
'ATP hydrolysis directly powers the chemical step of all enzymatic reactions.',
'ATP hydrolysis is required for enzyme-catalyzed reactions.',
],
[
'Catalysis by approximation brings in a strong nucleophile and electrophile for catalysis.',
'Catalysis by approximation decreases the local concentration of reactants.',
'Catalysis by approximation functions by randomly increasing substrate diffusion.',
'Catalysis by approximation increases entropy to drive reactions.',
'Catalysis by approximation involves aligning enzyme functional groups, NOT substrates.',
],
[
'All enzyme-catalyzed reactions proceed through a covalent enzyme-substrate intermediate.',
'Covalent bonding in the active site permanently links the enzyme to the product.',
'Covalent catalysis avoids charged intermediates by eliminating electron transfer steps.',
'Covalent catalysis eliminates the need for nucleophilic residues in the active site.',
'Covalent catalysis involves stable covalent bonds that permanently link enzyme to product.',
'Covalent catalysis prevents the formation of any charged intermediates.',
],
[
'Metal ion catalysis eliminates the need for substrate binding specificity.',
'Metal ion catalysis is effective only in acidic conditions.',
'Metal ion catalysis is effective only when metal ions form covalent bonds with substrates.',
'Metal ion cofactors in enzymes only serve structural roles.',
'The catalytic role of metal ions is limited to maintaining structural stability.',
'The only function of metal ions is to stabilize the tertiary structure of the enzyme.',
],
[
'The active site microenvironment cannot influence charge stabilization.',
],
[
'Substrate strain slows down enzymatic reactions by destabilizing intermediates.',
'Substrate distortion slows down enzymatic reactions by destabilizing intermediates.',
],
);
#==========================================================
# GLOBAL SETTINGS
#==========================================================
$topic = 'Enzyme Catalytic Strategies and Methods for Lowering Activation Energy';
my $local_random = PGrandom->new();
$local_random->srand($problemSeed);
my @mode_choices = ("TRUE", "FALSE");
$mode = $mode_choices[$local_random->random(0, $#mode_choices, 1)];
$num_distractors = 4;
#==========================================================
# SELECT GROUP
#==========================================================
my (@selected_group, @opposite_groups);
if ($mode eq "TRUE") {
$group_index = $local_random->random(0, scalar(@true_groups)-1, 1);
@selected_group = @{ $true_groups[$group_index] };
@opposite_groups = @false_groups;
} else {
$group_index = $local_random->random(0, scalar(@false_groups)-1, 1);
@selected_group = @{ $false_groups[$group_index] };
@opposite_groups = @true_groups;
}
#==========================================================
# PICK CORRECT + DISTRACTORS
#==========================================================
my $correct_index = $local_random->random(0, $#selected_group, 1);
$correct = $selected_group[$correct_index];
my @available_group_indices = (0 .. $#opposite_groups);
my @selected_distractor_indices = ();
while (@selected_distractor_indices < $num_distractors && @available_group_indices > 0) {
my $random_index = $local_random->random(0, scalar(@available_group_indices)-1, 1);
push @selected_distractor_indices, splice(@available_group_indices, $random_index, 1);
}
@distractors = ();
foreach my $group_idx (@selected_distractor_indices) {
my @group = @{ $opposite_groups[$group_idx] };
my $distractor_index = $local_random->random(0, $#group, 1);
my $distractor = $group[$distractor_index];
push @distractors, $distractor;
}
@choices = ($correct, @distractors);
#==========================================================
# SHUFFLE CHOICES (SEED-STABLE)
#==========================================================
my @choice_indices = (0 .. $#choices);
my @choice_shuffled = ();
while (@choice_indices) {
my $pick = $local_random->random(0, $#choice_indices, 1);
push @choice_shuffled, splice(@choice_indices, $pick, 1);
}
@choices = @choices[@choice_shuffled];
#==========================================================
# RADIO BUTTONS WITH A/B/C/D/E LABELS
#==========================================================
$rb = RadioButtons(
[@choices],
$correct,
labels => ['A','B','C','D','E'],
displayLabels => 1,
randomize => 0,
separator => '',
);
#==========================================================
# PGML
#==========================================================
BEGIN_PGML
[@ $mode eq "TRUE" ? "Which one of the following statements is TRUE about $topic?" : "Which one of the following statements is FALSE about $topic?" @]*
[_]{$rb}
END_PGML
ENDDOCUMENT();