## TITLE('The Structure of xDNA and XNA')
## DESCRIPTION
## Select the statement that is TRUE or FALSE about the structure of xDNA and XNA.
## ENDDESCRIPTION
## KEYWORDS('the structure of xDNA and XNA','true/false','multiple choice')
## DBsubject('Biotechnology')
## DBchapter('')
## DBsection('')
## Date('2026-05-31')
## 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 = (
[
'XNA has more than four nucleobase letters',
],
[
'XNA has a modified sugar backbone',
],
[
'XNA can base pair with natural DNA',
],
[
'XNA stands for Xeno Nucleic Acid',
],
[
'xDNA is wider than natural DNA',
],
[
'xDNA contains an extra benzene ring in its nucleobases',
],
[
'xDNA can base pair with natural DNA',
],
[
'xDNA stands for expanded DNA because it is larger',
],
[
'xDNA is also known as benzo-homologated DNA',
],
);
@false_groups = (
[
'xDNA has more than four nucleobase letters',
],
[
'xDNA has a modified sugar backbone',
],
[
'XNA cannot base pair with natural DNA',
],
[
'XNA stands for Xylo Nucleic Acid',
'XNA stands for Xenon Nucleic Acid',
'XNA stands for Xylose Nucleic Acid',
'XNA stands for Xylene Nucleic Acid',
'XNA stands for Xyloid Nucleic Acid',
'XNA stands for Xenopus Nucleic Acid',
'XNA stands for Xerotic Nucleic Acid',
'XNA stands for expanded DNA',
],
[
'XNA is wider than natural DNA',
],
[
'XNA contains an extra benzene ring in its nucleobases',
],
[
'xDNA cannot base pair with natural DNA',
],
[
'xDNA stands for extra DNA because it has more letters',
'xDNA stands for expanded DNA because it has more letters',
'xDNA stands for exon DNA because it has no introns',
'xDNA stands for excreted DNA because it is exported from the cell',
'xDNA stands for extinct DNA because it is obtained from ancient species',
'xDNA stands for extreme DNA because it does NOT denature even in boiling water (100°C)',
],
[
'XNA is also known as benzo-homologated DNA',
],
);
#==========================================================
# GLOBAL SETTINGS
#==========================================================
$topic = 'the structure of xDNA and XNA';
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();