Podcast
Questions and Answers
What type of protein is rhodopsin?
What type of protein is rhodopsin?
- A cytosolic protein
- An enzyme
- A G-protein-coupled receptor (correct)
- A transmembrane protein
What causes the closure of the cGMP-gated Na channels in photoreceptors?
What causes the closure of the cGMP-gated Na channels in photoreceptors?
- An increase in intracellular cGMP
- A decrease in intracellular cGMP (correct)
- A decrease in intracellular Ca2+
- An increase in intracellular Ca2+
What is the final step in phototransduction?
What is the final step in phototransduction?
- Activation of rhodopsin
- Hyperpolarization of the photoreceptor (correct)
- Binding and activation of the G protein, transducin
- Closure of cGMP-gated Na channels
Where does chromophore regeneration occur in photoreceptors?
Where does chromophore regeneration occur in photoreceptors?
What is the chemical reaction induced by photon absorption in photoreceptors?
What is the chemical reaction induced by photon absorption in photoreceptors?
What is the role of G protein, transducin, in phototransduction?
What is the role of G protein, transducin, in phototransduction?