Question

Outline the pathway in reflex arc in respond to shining a bright light into the eye​

Answer 1

Answer:

The eye's arc reflex to changes in light intensity is called photomotor reflex. whose pathway includes: a receptor in cells of the retina, an afferent pathway  -Optic nerve-, reception and processing center in Pretectal nucleus and efferent pathway given by oculomotor nerve and short ciliary nerves, whose efector is Pupil constricting muscles.

Explanation:

The reflex arch of the eye is what allows the pupil to close or open -by contracting or relaxing of pupil constrictor muscle, respectively- in response to changes in light intensity. This reflex has a direct pathway for each eye, and a cross pathway (consensual reflex) that stimulates the opposite eye.

The photomotor reflex -reflex arc- pathway is:

• Receptor: photoreceptor cells in the retina.
• Afferent pathway: Optic nerve
• Reception and processing center: Pretectal nucleus of the Midbrain.
• Efferent pathway: Parasympathetic nuclei of the oculomotor nerve → neurons of the ciliary ganglion → short ciliary nerves.
• Effector: Pupil constricting muscles.

The response will be a contraction of the constrictor muscle -pupil closure or myosis- in bright light, and a relaxation -pupil opening or midiriasis- in dark environments.