## DESCRIPTION ## Match each of the following alterations to chromosome structure with their corresponding descriptions. ## ENDDESCRIPTION ## KEYWORDS('alterations to chromosome structure','descriptions') ## DBsubject('Genetics') ## DBchapter('') ## DBsection('') ## Date('2026-07-12') ## Author('Neil R. Voss') ## Institution('Roosevelt University') DOCUMENT(); loadMacros( 'PGstandard.pl', 'PGML.pl', 'PGchoicemacros.pl', 'parserPopUp.pl', 'parserUtils.pl', 'PGgraders.pl', 'PGcourse.pl' ); our @ALPHABET = ('A' .. 'Z'); # ================================ # Full matching data # ================================ %match_data = ( 'non-disjunction' => [ 'the failure of sister chromatids to separate properly during cell division', 'the failure of homologous chromosomes to separate properly during cell division', ], 'deletion' => [ 'portion of the chromosome is missing', 'a sequence of DNA is left out during DNA replication', 'a part of a chromosome is left out during DNA replication', 'when a chromosome breaks a part of it is lost', 'can result from genes recombination where a part of a chromosome is lost', 'chromosome in which is missing a group of genes', ], 'duplications' => [ 'portion of the chromosome has been copied, resulting in extra genetic material', 'portion of the chromosome has been copied, resulting extra copies of a gene', 'can result from genes recombination where a part of a chromosome is replicated', 'chromosome that has an extra copy of a group of genes', ], 'reciprocal translocation' => [ 'can change a metacentric chromosome into a submetacentric chromosome', 'a pair of non-homologous chromosomes swapping genes with each other', 'the exchange of broken chromosome segments between two nonhomologous chromosomes', 'two detached fragments of two different chromosomes are switched', 'the Philadelphia chromosome is formed from this alteration of chromosomes 9 and 22', 'segments from two different chromosomes have been exchanged', ], 'non-reciprocal translocation' => [ 'the transferring of a chromosome segment from one chromosome to another non-homologous chromosome', 'the one-way transfer of a chromosomal segment from one non-homologous chromosome to another', 'a complete chromosome that also has a group of genes from another chromosome', ], 'paracentric inversion' => [ 'can change two monocentric chromosomes into an acentric chromosome', 'can change two monocentric chromosomes into a dicentric chromosome', 'the reversal of the gene order within a chromosome that does NOT include the centromere', 'two breaks and reversal of the genes occur on one arm of the chromosome', 'does NOT include the centromere and both breaks occur in one arm of the chromosome', 'a portion of a single chromosome arm has broken off, turned upside down, and reattached', 'a portion of a single chromosome arm has broken off, reversed, and reattached in its original place', 'can result from genes recombination where a part of a single chromosome arm is reversed', 'a group of genes on one arm of the chromosome is the reverse of the normal order', ], 'pericentric inversion' => [ 'a pair of homologous chromosomes that both have duplicated genes and missing genes', 'the reversal of the gene order in a chromosome that includes the centromere', 'two breaks and reversal of the genes occurs on both arms or sides of the centromere', 'centromere is included in the reversed loop that is formed during synapsis', 'reversal of the genes that includes both arms of the chromosome', 'includes the centromere and there is a break point in each arm', 'a portion of a chromosome that includes both arms has broken off, turned upside down, and reattached', 'a portion of a chromosome that includes both arms has broken off, reversed, and reattached', 'a group of genes including the centromere is the reverse of the normal order', ], 'Robertsonian translocation' => [ 'can change two acrocentric chromosomes into a metacentric chromosome', 'fusion of two chromosomes that have short p arms', 'caused by breaks at or near the centromeres of two acrocentric chromosomes', 'in humans, these alterations only occur with chromosomes 13, 14, 15, 21, and 22', 'entire chromosome has attached to another at the centromere', ], ); # ------------------------------- # Select N random keys # ------------------------------- my $n = 5; @all_keys = PGsort(sub { $_[0] lt $_[1] }, keys %match_data); my $local_seed = (defined($problemSeed) && $problemSeed ne '') ? $problemSeed : 1; my $local_random = new PGrandom($local_seed); my @indices = (0 .. $#all_keys); my @shuffled = (); while (@indices) { my $pick = $local_random->random(0, $#indices, 1); push @shuffled, splice(@indices, $pick, 1); } my @selected_keys = @all_keys[@shuffled[0..$n-1]]; # ------------------------------- # Build question/answer pairs # ------------------------------- # Each entry: [prompt, choice] @q_and_a = (); foreach my $key (@selected_keys) { my $values_ref = $match_data{$key}; my $i = $local_random->random(0, $#$values_ref, 1); my $value = $values_ref->[$i]; push @q_and_a, [ $value, $key ]; } # ------------------------------- # Randomize the questions # ------------------------------- my @q_indices = (0 .. $#q_and_a); my @q_shuffled = (); while (@q_indices) { my $pick = $local_random->random(0, $#q_indices, 1); push @q_shuffled, $q_and_a[splice(@q_indices, $pick, 1)]; } @q_and_a = @q_shuffled; # ------------------------------- # Sort the choices alphabetically # ------------------------------- @answers = (); push(@answers, (map { $_->[1] } @q_and_a)); @answers_sorted = PGsort(sub { $_[0] lt $_[1] }, @answers); # ------------------------------- # HTML-safe answer labels # ------------------------------- %answer_html = ( 'non-disjunction' => 'non-disjunction', 'deletion' => 'deletion', 'duplications' => 'duplications', 'reciprocal translocation' => 'reciprocal translocation', 'non-reciprocal translocation' => 'non-reciprocal translocation', 'paracentric inversion' => 'paracentric inversion', 'pericentric inversion' => 'pericentric inversion', 'Robertsonian translocation' => 'Robertsonian translocation', ); @answers_sorted_html = map { $answer_html{$_} || $_ } @answers_sorted; # ------------------------------- # Create answer index lookup # ------------------------------- our %answer_index; for (my $i = 0; $i <= $#answers_sorted; $i++) { $answer_index{$answers_sorted[$i]} = $i; } # ------------------------------- # PopUp/DropDown compatibility # ------------------------------- sub make_popup { return defined &DropDown ? DropDown(@_) : PopUp(@_); } # ------------------------------- # Create popup objects (blank default) # ------------------------------- my @answer_letters = @ALPHABET[0 .. $#answers_sorted]; my @answer_letters_with_blank = ('', @answer_letters); @answer_dropdowns = map { make_popup([ @answer_letters_with_blank ], $answer_index{$q_and_a[$_][1]} + 1 ) } 0 .. $#q_and_a; # ------------------------------- # Render the question # ------------------------------- HEADER_TEXT(< .pgml-bold { font-weight: 700; } .two-column { display: flex; flex-wrap: wrap; gap: 2rem; align-items: center; justify-content: space-evenly; } END_STYLE $question_text = 'Match each of the following alterations to chromosome structure with their corresponding descriptions.'; $note_text = 'Note: Each choice will be used exactly once.'; BEGIN_PGML [$question_text]* [$note_text]* [@ MODES(HTML => '

') @]* [@ join( "\n\n", map { '[_]{$answer_dropdowns[' . $_ . ']} ' . '*' . ($_ + 1) . '.* ' . '[$q_and_a[' . $_ . '][0]]*' } 0 .. $#q_and_a ) @]** [@ MODES(HTML => '

') @]* [@ join( "\n\n", map { chr(65 + $_) . '\\.' . ' ' . '[$answers_sorted_html[' . $_ . ']]*' } 0 .. $#answers_sorted ) @]** [@ MODES(HTML => '

') @]* END_PGML # ------------------------------- # Dynamic Partial Credit Based on $n # ------------------------------- $showPartialCorrectAnswers = 0; my @thresholds; my @scores; for (my $i = 1; $i <= $n; $i++) { push @thresholds, $i; push @scores, sprintf("%.2f", $i / $n); } install_problem_grader(~~&custom_problem_grader_fluid); $ENV{grader_numright} = [@thresholds]; $ENV{grader_scores} = [@scores]; $ENV{grader_message} = 'You can earn partial credit.'; # ------------------------------- # Solution # ------------------------------- $answer_list = join(', ', map { ($_ + 1) . '-' . $ALPHABET[$answer_index{$q_and_a[$_][1]}] } 0 .. $#q_and_a); BEGIN_PGML_SOLUTION The correct answers are: [$answer_list]. END_PGML_SOLUTION ENDDOCUMENT();