The special senses Flashcards
Where is information from sense organ processed?
-CNS- conscious or unconscious
What are the special senses?
-Sight, hearing, taste, smell
What system deal with taste?
-Gustatory
What system deals with smell?
-Olfactory
What are the accessory structures of the eye?
-Eyebrows, eyelids, eyelashes, conjunctiva, lacrimal, apparatus, extrinsic eye muscles
What is the lacrimal apparatus?
-Gland that is responsible for tears a part of the PNS
What is the conjunctiva?
-Transparent mucous membrane covering the cornea
What are the three tissue layers of the eye wall?
-Fibrous layer (outer), vascular layer and nervous tissue layer (inner)
What does the fibrous layer of the eye contain?
-Sclera (white of the eye) and cornea (front of the eye)
What does the vascular layer of the eye contain?
-Choroid (melanin containing cells), colliery body (cilliary muscles to change thickness of lens), iris (coloured and control pupil size)
What does the nervous tissue layer of the eye contain?
-The retina, outer pigmented to prevent light reflection and inner sensory retina
What are the chambers of the anterior segment?
-Anterior chamber, posterior chamber
How does light pass through the eye?
-Iris allows light into the eye, focused by the cornea, lens and humors onto the retina through the vitreous humour,between sons, ganglion cells and bipolar cells to photoreceptors next to the pigmented layer. Ganglion cell axons run on internal surface and converge at posterior of the eye to form optic nerve
What are the two types of photoreceptors ?
-Rods and cones
What are the features of the rod cells?
-More sensitive to light, allow vision in dim light by only black and white and not sharp
What are the features of cone cells?
-High acuity, so bright light needed. Colour vision, separated into 3 subtypes-blue, red and green