## DESCRIPTION
## Select the sensory transduction component that corresponds to the given function in signaling.
## ENDDESCRIPTION
## KEYWORDS('sensory transduction components','functions in signaling','which one','multiple choice')
## DBsubject('Cell Biology')
## 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 = 0;

#==========================================================
# QUESTION DATA
#==========================================================

# All questions data
@questions_data = (
  {
    'item_name' => '<strong>Receptor that binds odorants and activates G proteins</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'cAMP',
      'Gustducin',
      'IP<sub>3</sub>',
      'TRPM5',
      'Transducin',
      'Phosphodiesterase 6 (PDE6)',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'Olfactory receptor (GPCR)',
  },
  {
    'item_name' => '<strong>GPCR that initiates olfactory signaling in sensory neurons</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'Gustducin',
      'TRPM5',
      'Rhodopsin',
      'Transducin',
      'Phosphodiesterase 6 (PDE6)',
      'CNG channel (rod outer segment)',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'Olfactory receptor (GPCR)',
  },
  {
    'item_name' => '<strong>Odorant-activated GPCR upstream of cAMP production</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'G<sub>olf</sub>',
      'Gustducin',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'Rhodopsin',
      'Transducin',
      'Phosphodiesterase 6 (PDE6)',
      'cGMP',
    ],
    'correct' => 'Olfactory receptor (GPCR)',
  },
  {
    'item_name' => '<strong>Olfactory G protein that activates adenylyl cyclase</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'G<sub>olf</sub>',
      'Adenylyl cyclase (AC3)',
      'CNG channel (olfactory)',
      'IP<sub>3</sub>',
      'TRPM5',
      'Rhodopsin',
      'Tip link (hair cell bundle)',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'G<sub>olf</sub>',
  },
  {
    'item_name' => '<strong>G protein coupling olfactory receptors to cAMP signaling</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'G<sub>olf</sub>',
      'Adenylyl cyclase (AC3)',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'Rhodopsin',
      'Transducin',
      'Phosphodiesterase 6 (PDE6)',
      'CNG channel (rod outer segment)',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'G<sub>olf</sub>',
  },
  {
    'item_name' => '<strong>Heterotrimeric G protein used in olfactory GPCR pathways</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'G<sub>olf</sub>',
      'Gustducin',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'cGMP',
      'CNG channel (rod outer segment)',
      'Tip link (hair cell bundle)',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'G<sub>olf</sub>',
  },
  {
    'item_name' => '<strong>Enzyme that converts ATP to cAMP in olfactory neurons</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'Adenylyl cyclase (AC3)',
      'Gustducin',
      'TRPM5',
      'Rhodopsin',
      'Transducin',
      'cGMP',
      'Tip link (hair cell bundle)',
    ],
    'correct' => 'Adenylyl cyclase (AC3)',
  },
  {
    'item_name' => '<strong>Enzyme that produces cAMP as a second messenger</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'G<sub>olf</sub>',
      'Adenylyl cyclase (AC3)',
      'CNG channel (olfactory)',
      'TRPM5',
      'Rhodopsin',
      'Phosphodiesterase 6 (PDE6)',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'Adenylyl cyclase (AC3)',
  },
  {
    'item_name' => '<strong>ATP-to-cAMP enzyme downstream of G<sub>olf</sub></strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Adenylyl cyclase (AC3)',
      'CNG channel (olfactory)',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'IP<sub>3</sub>',
      'TRPM5',
      'Phosphodiesterase 6 (PDE6)',
      'Tip link (hair cell bundle)',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'Adenylyl cyclase (AC3)',
  },
  {
    'item_name' => '<strong>Second messenger made from ATP that rises during odor detection</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'Adenylyl cyclase (AC3)',
      'cAMP',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'TRPM5',
      'Rhodopsin',
      'Transducin',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'cAMP',
  },
  {
    'item_name' => '<strong>Signaling molecule that helps open olfactory CNG channels</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'G<sub>olf</sub>',
      'cAMP',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'IP<sub>3</sub>',
      'Phosphodiesterase 6 (PDE6)',
      'CNG channel (rod outer segment)',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'cAMP',
  },
  {
    'item_name' => '<strong>Cytosolic second messenger produced downstream of olfactory GPCRs</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Adenylyl cyclase (AC3)',
      'cAMP',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'IP<sub>3</sub>',
      'Phosphodiesterase 6 (PDE6)',
      'CNG channel (rod outer segment)',
      'Tip link (hair cell bundle)',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'cAMP',
  },
  {
    'item_name' => '<strong>Ion channel opened by cyclic nucleotides during odor detection</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'G<sub>olf</sub>',
      'CNG channel (olfactory)',
      'Gustducin',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'IP<sub>3</sub>',
      'Rhodopsin',
      'Phosphodiesterase 6 (PDE6)',
    ],
    'correct' => 'CNG channel (olfactory)',
  },
  {
    'item_name' => '<strong>Cyclic nucleotide gated channel that depolarizes olfactory neurons</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'CNG channel (olfactory)',
      'Gustducin',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'IP<sub>3</sub>',
      'Transducin',
      'Phosphodiesterase 6 (PDE6)',
      'Tip link (hair cell bundle)',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'CNG channel (olfactory)',
  },
  {
    'item_name' => '<strong>Allows Ca<sup>2+</sup> entry that can amplify the olfactory response</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Adenylyl cyclase (AC3)',
      'cAMP',
      'CNG channel (olfactory)',
      'Gustducin',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'IP<sub>3</sub>',
      'TRPM5',
      'Rhodopsin',
    ],
    'correct' => 'CNG channel (olfactory)',
  },
  {
    'item_name' => '<strong>Taste G protein used in bitter and sweet pathways</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'cAMP',
      'Gustducin',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'IP<sub>3</sub>',
      'Transducin',
      'CNG channel (rod outer segment)',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'Gustducin',
  },
  {
    'item_name' => '<strong>G protein that couples taste GPCRs to downstream second messengers</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'cAMP',
      'Gustducin',
      'IP<sub>3</sub>',
      'TRPM5',
      'Transducin',
      'Phosphodiesterase 6 (PDE6)',
      'CNG channel (rod outer segment)',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'Gustducin',
  },
  {
    'item_name' => '<strong>Heterotrimeric G protein in taste receptor signaling</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'G<sub>olf</sub>',
      'Gustducin',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'IP<sub>3</sub>',
      'Transducin',
      'CNG channel (rod outer segment)',
      'Tip link (hair cell bundle)',
    ],
    'correct' => 'Gustducin',
  },
  {
    'item_name' => '<strong>Enzyme that cleaves PIP<sub>2</sub> to generate IP<sub>3</sub></strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'G<sub>olf</sub>',
      'Adenylyl cyclase (AC3)',
      'CNG channel (olfactory)',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'IP<sub>3</sub>',
      'cGMP',
      'Tip link (hair cell bundle)',
    ],
    'correct' => 'Phospholipase C-&beta;2 (PLC-&beta;2)',
  },
  {
    'item_name' => '<strong>PIP<sub>2</sub>-cleaving enzyme in bitter, sweet, and umami taste signaling</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'G<sub>olf</sub>',
      'CNG channel (olfactory)',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'IP<sub>3</sub>',
      'Rhodopsin',
      'Phosphodiesterase 6 (PDE6)',
      'Tip link (hair cell bundle)',
    ],
    'correct' => 'Phospholipase C-&beta;2 (PLC-&beta;2)',
  },
  {
    'item_name' => '<strong>Enzyme that produces IP<sub>3</sub> downstream of taste GPCRs</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Adenylyl cyclase (AC3)',
      'Gustducin',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'TRPM5',
      'Transducin',
      'Phosphodiesterase 6 (PDE6)',
      'cGMP',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'Phospholipase C-&beta;2 (PLC-&beta;2)',
  },
  {
    'item_name' => '<strong>Second messenger that triggers Ca<sup>2+</sup> release from ER stores</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Adenylyl cyclase (AC3)',
      'cAMP',
      'CNG channel (olfactory)',
      'IP<sub>3</sub>',
      'TRPM5',
      'Rhodopsin',
      'Transducin',
      'Tip link (hair cell bundle)',
    ],
    'correct' => 'IP<sub>3</sub>',
  },
  {
    'item_name' => '<strong>Diffusible messenger that raises cytosolic Ca<sup>2+</sup> in taste cells</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'G<sub>olf</sub>',
      'IP<sub>3</sub>',
      'TRPM5',
      'Transducin',
      'Phosphodiesterase 6 (PDE6)',
      'cGMP',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'IP<sub>3</sub>',
  },
  {
    'item_name' => '<strong>Molecule that opens IP<sub>3</sub> receptors on internal Ca<sup>2+</sup> stores</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'G<sub>olf</sub>',
      'Adenylyl cyclase (AC3)',
      'CNG channel (olfactory)',
      'Gustducin',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'IP<sub>3</sub>',
      'Rhodopsin',
    ],
    'correct' => 'IP<sub>3</sub>',
  },
  {
    'item_name' => '<strong>Cation channel activated downstream of Ca<sup>2+</sup> signaling in taste cells</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'Adenylyl cyclase (AC3)',
      'Gustducin',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'TRPM5',
      'Rhodopsin',
      'Phosphodiesterase 6 (PDE6)',
      'CNG channel (rod outer segment)',
    ],
    'correct' => 'TRPM5',
  },
  {
    'item_name' => '<strong>Channel that helps depolarize taste receptor cells after GPCR activation</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'G<sub>olf</sub>',
      'Adenylyl cyclase (AC3)',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'IP<sub>3</sub>',
      'TRPM5',
      'Rhodopsin',
      'cGMP',
      'CNG channel (rod outer segment)',
    ],
    'correct' => 'TRPM5',
  },
  {
    'item_name' => '<strong>Ion channel involved in taste transduction downstream of IP<sub>3</sub></strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'G<sub>olf</sub>',
      'Adenylyl cyclase (AC3)',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'IP<sub>3</sub>',
      'TRPM5',
      'Tip link (hair cell bundle)',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'TRPM5',
  },
  {
    'item_name' => '<strong>Opsin plus retinal that activates transducin when retinal isomerizes</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'G<sub>olf</sub>',
      'Adenylyl cyclase (AC3)',
      'cAMP',
      'CNG channel (olfactory)',
      'Gustducin',
      'Rhodopsin',
      'Transducin',
      'Tip link (hair cell bundle)',
    ],
    'correct' => 'Rhodopsin',
  },
  {
    'item_name' => '<strong>Light-activated GPCR in rod photoreceptors</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Gustducin',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'TRPM5',
      'Rhodopsin',
      'Phosphodiesterase 6 (PDE6)',
      'cGMP',
      'Tip link (hair cell bundle)',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'Rhodopsin',
  },
  {
    'item_name' => '<strong>Photopigment that starts rod phototransduction</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'G<sub>olf</sub>',
      'Gustducin',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'IP<sub>3</sub>',
      'Rhodopsin',
      'CNG channel (rod outer segment)',
      'Tip link (hair cell bundle)',
    ],
    'correct' => 'Rhodopsin',
  },
  {
    'item_name' => '<strong>G protein that activates PDE6 in rod phototransduction</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'Adenylyl cyclase (AC3)',
      'CNG channel (olfactory)',
      'Gustducin',
      'IP<sub>3</sub>',
      'Transducin',
      'cGMP',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'Transducin',
  },
  {
    'item_name' => '<strong>Rod G protein linking rhodopsin to cGMP breakdown</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'G<sub>olf</sub>',
      'Gustducin',
      'IP<sub>3</sub>',
      'Rhodopsin',
      'Transducin',
      'Phosphodiesterase 6 (PDE6)',
      'Tip link (hair cell bundle)',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'Transducin',
  },
  {
    'item_name' => '<strong>Heterotrimeric G protein in the visual cascade</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'G<sub>olf</sub>',
      'cAMP',
      'Gustducin',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'IP<sub>3</sub>',
      'Transducin',
      'Phosphodiesterase 6 (PDE6)',
      'CNG channel (rod outer segment)',
    ],
    'correct' => 'Transducin',
  },
  {
    'item_name' => '<strong>Enzyme that hydrolyzes cGMP in rods after light activation</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'G<sub>olf</sub>',
      'cAMP',
      'Gustducin',
      'IP<sub>3</sub>',
      'Rhodopsin',
      'Phosphodiesterase 6 (PDE6)',
      'CNG channel (rod outer segment)',
    ],
    'correct' => 'Phosphodiesterase 6 (PDE6)',
  },
  {
    'item_name' => '<strong>Enzyme that lowers cGMP concentration during phototransduction</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'G<sub>olf</sub>',
      'Adenylyl cyclase (AC3)',
      'Gustducin',
      'Transducin',
      'Phosphodiesterase 6 (PDE6)',
      'CNG channel (rod outer segment)',
      'Tip link (hair cell bundle)',
    ],
    'correct' => 'Phosphodiesterase 6 (PDE6)',
  },
  {
    'item_name' => '<strong>cGMP-degrading enzyme downstream of transducin</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Adenylyl cyclase (AC3)',
      'Gustducin',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'TRPM5',
      'Rhodopsin',
      'Transducin',
      'Phosphodiesterase 6 (PDE6)',
      'cGMP',
    ],
    'correct' => 'Phosphodiesterase 6 (PDE6)',
  },
  {
    'item_name' => '<strong>Second messenger that keeps rod CNG channels open in the dark</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Adenylyl cyclase (AC3)',
      'CNG channel (olfactory)',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'IP<sub>3</sub>',
      'TRPM5',
      'Transducin',
      'Phosphodiesterase 6 (PDE6)',
      'cGMP',
    ],
    'correct' => 'cGMP',
  },
  {
    'item_name' => '<strong>Signaling nucleotide that falls in light, closing CNG channels</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'G<sub>olf</sub>',
      'Adenylyl cyclase (AC3)',
      'CNG channel (olfactory)',
      'Gustducin',
      'Transducin',
      'Phosphodiesterase 6 (PDE6)',
      'cGMP',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'cGMP',
  },
  {
    'item_name' => '<strong>Cyclic nucleotide that gates rod outer segment ion channels</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'G<sub>olf</sub>',
      'Adenylyl cyclase (AC3)',
      'CNG channel (olfactory)',
      'Gustducin',
      'IP<sub>3</sub>',
      'Rhodopsin',
      'Transducin',
      'cGMP',
    ],
    'correct' => 'cGMP',
  },
  {
    'item_name' => '<strong>Ion channel that closes when cGMP falls, hyperpolarizing the rod</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'G<sub>olf</sub>',
      'Adenylyl cyclase (AC3)',
      'TRPM5',
      'Transducin',
      'Phosphodiesterase 6 (PDE6)',
      'cGMP',
      'CNG channel (rod outer segment)',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'CNG channel (rod outer segment)',
  },
  {
    'item_name' => '<strong>cGMP-gated channel that is open in darkness and closes in light</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Adenylyl cyclase (AC3)',
      'IP<sub>3</sub>',
      'Rhodopsin',
      'Transducin',
      'cGMP',
      'CNG channel (rod outer segment)',
      'Tip link (hair cell bundle)',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'CNG channel (rod outer segment)',
  },
  {
    'item_name' => '<strong>Rod channel controlled by cGMP levels</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'Adenylyl cyclase (AC3)',
      'Gustducin',
      'IP<sub>3</sub>',
      'TRPM5',
      'cGMP',
      'CNG channel (rod outer segment)',
      'Tip link (hair cell bundle)',
    ],
    'correct' => 'CNG channel (rod outer segment)',
  },
  {
    'item_name' => '<strong>Mechanical tether that transmits force to open mechanotransduction channels</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'Adenylyl cyclase (AC3)',
      'Gustducin',
      'TRPM5',
      'Rhodopsin',
      'Phosphodiesterase 6 (PDE6)',
      'CNG channel (rod outer segment)',
      'Tip link (hair cell bundle)',
    ],
    'correct' => 'Tip link (hair cell bundle)',
  },
  {
    'item_name' => '<strong>Link between stereocilia that helps gate transduction channels</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Adenylyl cyclase (AC3)',
      'CNG channel (olfactory)',
      'Gustducin',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'IP<sub>3</sub>',
      'TRPM5',
      'Rhodopsin',
      'Tip link (hair cell bundle)',
    ],
    'correct' => 'Tip link (hair cell bundle)',
  },
  {
    'item_name' => '<strong>Structure whose tension changes during stereocilia deflection</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'G<sub>olf</sub>',
      'cAMP',
      'Gustducin',
      'IP<sub>3</sub>',
      'TRPM5',
      'Rhodopsin',
      'CNG channel (rod outer segment)',
      'Tip link (hair cell bundle)',
    ],
    'correct' => 'Tip link (hair cell bundle)',
  },
  {
    'item_name' => '<strong>Ion channel opened by stereocilia deflection in hearing and balance</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'G<sub>olf</sub>',
      'CNG channel (olfactory)',
      'Gustducin',
      'Rhodopsin',
      'Transducin',
      'cGMP',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'Mechanotransduction channel (hair cell MET channel)',
  },
  {
    'item_name' => '<strong>Mechanically gated channel that allows cation influx in hair cells</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'Olfactory receptor (GPCR)',
      'G<sub>olf</sub>',
      'Adenylyl cyclase (AC3)',
      'Gustducin',
      'TRPM5',
      'Rhodopsin',
      'CNG channel (rod outer segment)',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'Mechanotransduction channel (hair cell MET channel)',
  },
  {
    'item_name' => '<strong>Allows K<sup>+</sup> influx from K<sup>+</sup> rich endolymph to depolarize hair cells</strong>',
    'plural_choice' => 'sensory transduction components',
    'singular_item' => 'function in signaling',
    'choices' => [
      'G<sub>olf</sub>',
      'cAMP',
      'Gustducin',
      'Phospholipase C-&beta;2 (PLC-&beta;2)',
      'TRPM5',
      'Phosphodiesterase 6 (PDE6)',
      'Tip link (hair cell bundle)',
      'Mechanotransduction channel (hair cell MET channel)',
    ],
    'correct' => 'Mechanotransduction channel (hair cell MET channel)',
  },
);

#==========================================================
# SELECT RANDOM QUESTION
#==========================================================

my $local_random = PGrandom->new();
$local_random->srand($problemSeed);

$question_idx = $local_random->random(0, scalar(@questions_data) - 1, 1);
$q = $questions_data[$question_idx];

$item_name = $q->{'item_name'};
$plural_choice = $q->{'plural_choice'};
$singular_item = $q->{'singular_item'};
@choices = @{ $q->{'choices'} };
$correct = $q->{'correct'};

#==========================================================
# 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];

#==========================================================
# BUILD RADIO BUTTONS
#==========================================================

$rb = RadioButtons(
  [@choices],
  $correct,
  labels        => 'ABC',
  displayLabels => 1,
  randomize     => 0,
  separator     => '<div style="margin-bottom: 0.7em;"></div>',
);

#==========================================================
# PGML
#==========================================================

BEGIN_PGML

Which one of the following [$plural_choice]* corresponds to the [$singular_item]* [$item_name]*?

[_]{$rb}

END_PGML

BEGIN_PGML_SOLUTION

The correct answer is: [$correct]*

END_PGML_SOLUTION

ENDDOCUMENT();