260 likes | 339 Views
Sensory Division. Sight Hearing Smell Taste Touch. Vision. Specialized organs: the eyes Role: Light image sensing 3 layers in eyes. Outer Layer. Sclera ( “ whites”) Maintains shape and attaches muscle Cornea Clear, protective layer Light entry. Middle Layer.
E N D
Sensory Division Sight Hearing Smell Taste Touch
Vision Specialized organs: the eyes Role: Light image sensing 3 layers in eyes
Outer Layer • Sclera (“whites”) • Maintains shape and attaches muscle • Cornea • Clear, protective layer • Light entry
Middle Layer • Anterior Chamber • Filled with aqueous humor
Middle Layer • Iris - pigmented • Holds blood vessels • Regulates pupil size muscles
Middle Layer • Pupil • Black disk • Opening to interior of the eye
Middle Layer • Lens • Immediately behind pupil • Convex • Bends light for focus
Middle Layer • Vetreous Chamber • Filled with vetreous humor
Inner Layer • Retina • Photoreceptors • Makes images
Photoreceptors • Rods – 125 million • Black & white (used in dim light) • Cones – 7 million • 3 types • Color (used in bright light)
Hearing Specialized organs: the ears Role: Detecting sound (pitch & volume)
Hearing • Auditory canal Tympanic membrane (eardrum) 3 bones • Malleus (hammer) • Incus (anvil) • Stapes (stirrups)
Cochlea • Moves sound to the auditory nerve • Organ of Corti contains hair cells that bend and create action potentials
Balance The ear is also responsible for maintaining balance But how, Mr. Schoedel?!
Balance • 3 fluid-filled semicircular canals in the inner ear • Filled with fluid • Lined with hair cells that have otoliths (calcium carbonate) on their heads
Smell Perceived by specialized chemoreceptors in the nasal passage called olfactory receptors Not much else is known
Taste • Related to smell • Perceived by specialized chemoreceptors called taste buds • Four types: Sweet, Salty, Sour, Bitter
Touch • Variety of receptors • Touch • Pressure • Tension • Temperature • Pain
Touch • Number of receptors vary • 3 heat for 1 cold • More touch receptors in the face, lips, fingers, and toes • More pain receptors at hands and mouth
Touch • Types of pain sensations • Burning pain • Prickling pain • Aching pain