1. Vision Sense organs: eye Receptor cell: photoreceptor
Receptor signal transduction mechanism: activated opsin membrane receptor (transducin G-protein) activates cGMP path to hyperpolarization in light
Pathway of conduction: photoreceptor  bipolar cell ganglion cell (as optic nerve)  thalamus  visual cortex  visual assoc. area

4. Information passes from retinal photoreceptor cells to bipolar neurons to ganglion neurons. (There is some convergence.)
photoreceptors

7. What effect would a decrease in phosphodiesterase activity in photoreceptor cells have on vision?
A decrease in phosphodiesterase activity would lead to a higher level of intracellular cGMP. This rise would, in turn, keep the gated cation channels open and keep the photoreceptors depolarized.
This would decrease the ability of receptor neurons to respond to photons. And reduce the receipt of visual sensory information.

8. Vision
Pathway of conduction: photoreceptor  bipolar cell ganglion cell (as optic nerve)  thalamus  visual cortex  visual assoc. area

10. ‘Shortsighted’ or ‘Near-sighted’
‘Farsighted’

11. Eye Muscles Superior Oblique (IV) Lateral Rectus (VI) Inferior Rectus
All others (CN III)
Inferior Rectus
Medial Rectus,
Superior rectus
Inferior Oblique
Eye Lid: Levator Palpebrae