## TITLE('The Enzyme Function of Chymotrypsin')
## DESCRIPTION
## Select the statement that is TRUE or FALSE about the enzyme function of Chymotrypsin.
## ENDDESCRIPTION
## KEYWORDS('the enzyme function of Chymotrypsin','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 = (
[
'Chymotrypsin prefers to cleave after large aromatic amino acids.',
],
[
'The shape of the S1 pocket of Chymotrypsin helps determine which residues are cut.',
'The amino acid tyrosine fits well into the S1 pocket of Chymotrypsin.',
'The amino acid phenylalanine fits well into the S1 pocket of Chymotrypsin.',
'The amino acid tryptophan fits well into the S1 pocket of Chymotrypsin.',
],
[
'The S1 pocket of Chymotrypsin is designed to bind hydrophobic side chains.',
'The S1 pocket of Chymotrypsin is deep and hydrophobic.',
'The substrate specificity of Chymotrypsin is mostly due to the properties of its S1 pocket.',
],
[
'Chymotrypsin helps break down dietary proteins into smaller peptides.',
'Chymotrypsin is used to digest proteins in the small intestine.',
],
[
'Chymotrypsin sometimes cleaves after hydrophobic amino acids, leucine and methionine.',
],
[
'Chymotrypsin works in two main phases, cutting and resetting.',
'The free Chymotrypsin enzyme is regenerated using water in the second phase of the reaction.',
],
[
'Chymotrypsin contains a cleft where peptide bonds are broken.',
],
);
@false_groups = (
[
'Chymotrypsin prefers to cleave after positively charged amino acids.',
'Chymotrypsin cleaves randomly along the protein backbone.',
'Chymotrypsin prefers to cleave after negatively charged amino acids.',
'Chymotrypsin prefers to cleave after small, polar amino acids.',
'Chymotrypsin cleaves only at the N-terminus of peptides.',
],
[
'The S1 pocket of Chymotrypsin is shallow and positively charged.',
'The S1 pocket of Chymotrypsin is shallow and negatively charged.',
'The S1 pocket of Chymotrypsin is deep and positively charged.',
'The S1 pocket of Chymotrypsin is deep and negatively charged.',
'The S1 pocket of Chymotrypsin prefers charged polar side chains.',
],
[
'Chymotrypsin only acts on carbohydrate side chains.',
'Chymotrypsin only acts on triglyceride fatty acid side chains.',
'Chymotrypsin works to break down polysaccharides.',
'Chymotrypsin assembles peptide chains from free amino acids.',
'Chymotrypsin digests carbohydrates in the stomach.',
'Chymotrypsin digests fats and oils in the stomach.',
'Chymotrypsin is primarily used to digest nucleic acids.',
'Chymotrypsin is active in the acidic environment of the stomach.',
],
[
'Chymotrypsin sometimes cleaves after small amino acids, glycine and alanine.',
'Chymotrypsin sometimes cleaves after polar amino acids, serine and threonine.',
'Chymotrypsin sometimes cleaves after the negatively charged amino acid, glutamine.',
'Chymotrypsin sometimes cleaves after the positively charged amino acid, lysine.',
],
[
'Chymotrypsin cuts proteins all at once, without forming intermediates.',
],
[
'Water has no role in the enzyme function of Chymotrypsin.',
'Chymotrypsin does NOT require water at any point in its mechanism.',
],
[
'Chymotrypsin requires ATP to cleave peptide bonds.',
],
[
'The S1 pocket of Chymotrypsin binds metal ions to stabilize the substrate.',
],
);
#==========================================================
# GLOBAL SETTINGS
#==========================================================
$topic = 'the enzyme function of Chymotrypsin';
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();