The Visual Nervous System and Upper Cranial Nerves Flashcards
The somatic nervous system innervates what?
Musculoskeletal muscle and sense organs of the skin
The sympathetic nervous system has a what type of outflow?
Thoracolumbar
The parasympathetic nervous system has a what type of outflow?
Cervicosacral
Your lateral rectus eye muscle does what?
Abducts the eye
Label the following muscles of the eye.
What does the superior rectus do?
Ellevates, adduct and intort the eyeball
What does your inferior rectus do?
Depress, adduct and extort the eyeball
What does your superior oblique muscle do?
Abduct, depress and intort the eyeball.
What is the sclera of the eye?
The tough fibrous outer coating.
What does the cornea do?
Refracts the light entering the eye
What are the two layers of the choroid of the eye, what do they do?
Outer pigmented layer that absrobs light
Inner highly vascular layer
What does the ciliary body do?
The ciliary body produces the fluid in the eye called aqueous humor. It also contains the ciliary muscle.
What does the ciliary muscle do?
Changes the shape of the lens when your eyes focus on a near object.
What are the two layers of the retina?
Outer pigmented layer and inner nervous layer
What is the function of the pigmented layer of the eye?
To absorb light
What is the macula lutea?
An oval yellowish area surrounding the fovea near the centre of the retina in the eye, which is the region of keenest vision.
How do photoreceptor cells work?
Phototransuction:
Photoreceptor cells absorb photons triggering membrane potentials, converting light into biological messages.
Outline the rods of the eye.
- Rods are responsible for vision at low light levels.
- Do not mediate colour vision
- Low spatial acuity
Outline cone cells, their function and when they are used.
- Active at higher light levels (phototopic).
- Capable of colour vision.
- Responsible for high spatial acuity.
What are the three types of cone cells?
Short, middle and long-wavelength sensitive.