The Senses Flashcards
2 general function of the senses
- obtain info from environment
2. help you survive
2 general structures of the senses
- specialized sense organs- act as transducers (transforms energy)
- sense receptors
5 types of sense receptors
- photoreceptors - detect light - eyes
- chemoreceptors - detect chemicals - tongue, nose
- thermoreceptors - detect heat, cold - skin
- mechanoreceptors - detect pressure - skin
- pain receptors - detect pain
2 types of human vision
- binocular vision - 2 eyes
2. stereoscopic vision - see 3D
eyeball diameter
1 inch
3 layers of wall of the eye
- sclera- outer
- choroid- middle
- retina- inner
part of eye under sclera
cornea - transparent front bulge
part of eye under choroid
iris - pigment gives eye color, muscles regulate pupil
3 parts of retina
- photoreceptors
- fovea
- optic disc
2 types of photoreceptors
- cones- bright light, colors
2. rods- dim light, shadows
describe fovea
sharpest point on retina, all cones, no rods
describe optic disc
- blind spot, no rods or cones
2. entry of optic nerve
3 parts of the interior structure of eye
- aqueous humor -fluid between cornea and lens
- vitreous humor - fluid behind lens
- lens- behind pupil
muscles that change the curvature of eye lens are called..
CILIARY muscles
define conjuctiva
membrane covering sclera and inner eyelid; secretes mucus for eye lubrication