Chapter 8 Vocab Special Senses

For Anatomy and Physiology for school

Tarsal Glands

Sebaceous glands associated with the eyelid edges

Conjunctiva

Delicate Membrane lines the eyelids & covers part of the outer surface

Lysozyme

Enzyme that destroys bacteria

Sclera

Whiter outer layer that protects the eyeball

Cornea

Transparent layer forming the front of the eye

Choroid

Posterior Vascular layer that contains blood vessels contain a dark pigment

Ciliary Body

Smooth muscle structures attached to the lens

Ciliary Zonule

Suspensory ligament

Iris

Pigmented, has a round opening behind the cornea of the eye

Pupil

Dark circular opening the center of the iris of the eye and regulates the amount of light

Retina

Sensory layer of the back of the eyeball containing cells that are sensitive to light

Photoreceptors

Receptor shaped like rods & cones that responds to light

Rods

Receptor cells that dim light and peripheral vision perception in gray tones shaped like a rod

Cones

Receptor cell detailed color vision, dense center of the retina

Optic Disc

Where the Optic Nerve leaves the eyeball

Fovea Centralis

A tiny pit that contains only lens

Cataracts

Clouding of the eye

Sclera Venous Sinus

Aqueous humor reabsorbed into venous blood

Glaucoma

Eye disease that causes vision loss / blindness by damaging nerve

Refracted Light

Bending of the light

Accommodation

Ability to focus specifically for close object less than 20 ft away

Convergence

Reflexive movements of the eyes medially when viewing close objects

Photopupillary Reflex

When eye is exposed to bright light the pupil constricts & prevents the light from damaging the photoreceptors

Accommodation Reflex

When the pupil constricts reflexively when you view close objects

Emmetropia

State of vision where images are correctly brought to focus on the retina

Myopia

Nearsightedness

Hyperopia

Farsightedness

Presbyopia

Farsightedness caused by elasticity of the lens in the eye which happens middle & old age

Astigmatism

Defect, when the the Cornea has different shape than normal

Mechanoreceptors

Receptors that respond to physical forces like touch or sound

Otitis Media

Inflammation of the middle ear

Ossicles

3 smallest bones in the body in the middle ear

Osseus Labyrinth

Also known as Bony Labyrinth it’s a maze of bony chambers within the temporal bone filled with perilymph

Tectorial Membrane

Gel like membrane that covers the hair bonds in the Cochlea

Perilymph

Fluid between membranous labyrinth (soft tissue) & bone that enclose it.

Membranous Labyrinth

Groups of ducts & chambers filled with endolymphatic fluid

Endolymph

Thicker fluid that is in Membranous Labyrinth

Static Equilibrium

Receptors reports position of the head when the body is at rest

Dynamic Equilibrium

Receptors report angular/rotational movements of the head

Otoliths

Tiny ear stones made of calcium salts

Basilar Membrane

The “basement” membrane in cochlear duct that vibrates to transmit sound waves & houses receptors

Chemoreceptors

Sensory cell/organ responsive to chemical stimuli

Olfactory Receptors

Receptors for sense of smell

Olfactory Hairs

Tiny hairs containing olfactory receptors that bind to odor molecules

Papilae

Peg like projections

Basal cells

Lower part of the epidermis