Please enable JavaScript.
Coggle requires JavaScript to display documents.
Sensory Receptors and Anatomy of the Eye (Sensory receptors based on type…
Sensory Receptors and Anatomy of the Eye
Sensory receptors based on stimulus origin
Interoceptors:
Stimulus from inside (interior).
Location: Internal organs (like heart beating)
Proprioceptors:
Stimulus from muscle / tendons / ligaments / joins
Exteroceptors:
Stimulus from the environment.
Location: Skin, special sense organs (like hearing and sight)
Sensory receptors based on type of stimulus
Chemoreceptor:
Sensitive to chemicals (smell and taste) and checking chemical levels in blood (pH)
Nociceptor:
Sensitive to pain. (Remember Noxious = Danger. Noc = Pain)
Photoreceptor:
Sensitive to light
Mechanoreceptor:
Sensitive to pressure, touch, vibration, stretch
Thermoreceptor:
Sensitive to temperature. There are some receptors for warmth, and some for cold
Baroreceptor:
Type of Mechanoreceptor: Sensitive to blood pressure.
Gross and microscopic anatomy of the eye
Three Tunics (layers) of the eye
Vascular Layer
Choroid -
Vascular and nourishes all other tunics. Also absorbs light and prevents light from scattering. Continuous with the Ciliary body.
Ciliary body -
muscle that changes the shape of the lens
Inner Layer
Retina -
Contains the photoreceptors. Axons from photoreceptors converge to become the optic nerve (in the back of the eye)
Fibrous Layer
Sclera -
Outer Layer (white color) of the eye. Made up of Dense Connective Tissue. Protective layer. It is the anchor for muscles, and gives the eye it's shape.
Cornea -
Transparent, allows light into the eye and helps focus that light.
Functions of Rods and Cones
Rods -
Sensitive to light (shades of light and dark) used mostly in dim light. There are more rods than cones in the eye.
Cones -
Sensitive to color. Cones work best in bright light.
Location and Function of the lens and iris
Iris -
Posterior to cornea, dilate or constrict to allow more or less light into the eye
Pupil -
opening in the iris
Lens -
Posterior to the iris, focuses light onto the retina
Location and function of the Optic Disc, Macula Lutea, and Fovea Centralis
Macula Luea -
Posterior pole, made up of only cones. This is the sharpest vision.
Fovea Centralis -
Center of Macula Lutea
Optic Disc -
Axons converge to form optic nerve (canal in the back of the eye). There are no photoreceptors (rods and cones) in the optic disc. This is the "blind spot"
Posterior and Anterior cavities and their humor
Posterior Segment -
Filled with VITREOUS humor. Viscous liquid transmits light and supports the retina and lens. It helps maintain pressure and the shape of the eye.
Anterior Segment -
Filled with AQEUOUS humor. Aqueous humor is a watery substance that transmits light, nourishes the lens and the cornea, and helps maintain pressure and shape of the eye.