Berry College: BIO 207- Lab 1 (Eye and Ear)

Optic Nerve

axons leave the eye and relay visual information to the brain

Aqueous Humor

provides nutrients to cornea, lens

Lens

focuses light on the retina

Suspensory Ligament

holds lens, adjust lens shape with ciliary body

Vitreous Humor

maintains pressure on retina

Pupil

adjusts amount of light that reaches the retina

Sclera

site of muscle attachment, protects, anchors eye

Cornea

refracts light

Choroid

provides nutrients to retina

Ciliary Body

smooth muscle that adjusts shape of lens to bend light to fovea

Iris

contains muscle that change the size of pupil

Ora Serrata

site where ciliary body meets retina

Retina

responsive to light, phototransduction

Optic Disc

site of axons leaving eye, vessels entering

Macula Lutea

site with high density of photoreceptors, contains, contains fovea centralis

Fovea Centralis

indented center of the macula lutea, allows for detailed vision

Photoreceptors

responsive to light energy, relay signal to bipolar cells

Superior and inferior Rectus Muscles

extrinsic eye muscles that respectively move the eye superiorly and inferiorly

Medial and Lateral Rectus Muscles

extrinsic eye muscles that respectively move the eye medially and laterally

Superior Oblique Muscle

extrinsic eye muscles that moves the eye inferiorly and laterally

Inferior Oblique Muscle

extrinsic eye muscles that elevates eye superiorly and laterally

Blind Spot Test

- Illustrates the fact that the optic disk has no receptors

- focus on x while paper moves closer until the dot disappears

Visual Acuity Test

- tests ability to distinguish outlines and details

- uses Shelleen's Chart

- 20/20 is normal

Astigmatism Test

- tests for distortion of the lens and/or cornea

- if any line in a ray of black lines looks fuzzy or less dark, it could indicate some distortion

Afterimages Test

- exhibits bleaching of pigments in photoreceptors and resynthesis of pigments

- after staring at a light, a positive image appears with eyes closed, and then a negative image appears after a time with eyes open

Color Blindness Test

- tests cones' ability to detect different colors of light

- most genes for color vision appear on the x chromosome

- if one x chromosomes has a defect a normal x chromosome can counter it

- test using images made with various colored dots

Depth Perception Test

- tests retinas ability to accurately triangulate distance

- attempt to quickly place a pencil into a test tube at an arm's length away

Outer Ear

the outermost part of the ear, consisting of the pinna, the external auditory canal, and tympanic membrane

(air filled)

Middle Ear

the chamber between the eardrum and cochlea containing ear ossicles and pharyngotympanic tube

(air filled)

Inner Ear

the innermost part of the ear, containing the cochlea, semicircular canals, vestibule, and vestibulocochlear nerve

(fluid filled)

Auricle (pinna)

external portion of the ear that funnels sound into the ear

External auditory canal

portion of the outer ear that transmits sound waves from the pinna to the tympanic membrane

Tympanic membrane

a structure that separates the outer ear from the middle ear and vibrates in response to sound waves

Ear ossicles

three small bones (malleus, incus, and stapes) located in the middle ear cavity that serve to transmit sound vibrations to the inner ear

Pharyngotympanic tube

connects the middle ear to the nasopharynx

Cochlea

a coiled, bony, fluid-filled tube containing cochlear duct and spiral organ in the inner ear that transmits sound

Semicircular canals

three canals within the inner ear that contain specialized receptor cells that are involved in balance and equilibrium

Vestibule

contains structures that help you sense gravity and linear acceleration

Vestibulocochlear nerve

cranial nerve involved in hearing and balance

Balance/equilibrium test

- demonstrates the brains attempt to regulate input from eyes and vestibular apparatus

- partner spins you on a stool and you attempt to remain focused ahead

- the fluid inside the inner ear continues to move as your head stops

Lab 2 pre-lab: Which of the following hormones is NOT secreted by the hypothalamus?

- growth hormone

Lab 2 pre-lab: (T/F) The pancreas is both an exocrine and an endocrine gland

true

Lab 2 pre-lab: In an individual with Type I diabetes:

Cells of the pancreas are attacked by the immune system

Lab 2 pre-lab: A hormone that causes release of another hormone is referred to as a(n) _________________ hormone

tropic