Eyes

optic disc (blind spot)

*site where optic nerve leaves the eye *lacks photoreceptors

Blind spot

An area toward the back of the retina that doesn't register incoming light rays

Lysozyme

An enzyme in tears that inhibits the growth of bacteria on the front of the eyeball

Cornea

Anteriormost clear part of fibrous tunic

Sclera

Fibrous tunic, white and opaque

aqueous humor

Fluid that fills the anterior segment of the eye, provides nutrients to the lens and cornea

Optic nerve

Formed by ganglion neurons, transmits impulses from the retina to the brain

Anterior cavity of eye

Further broken into anterior chamber-fro cornea to iris and posterior chamber-fro iris to ciliary body

vitreous humor

Gel-like substance, filling the posterior segment of the eyeball, helps reinforce the eyeball

vitreous humor

Helps support lens Rolds retina in place Contributes to intraoculsr pressure

Conjunctiva

Thin transparent mucous membrane covering the inner surfaces of the eyelids and outer surface of eyes

Lens

This structure aids in focusing light rays on the retina

Retina

Tunic concerned w image formation

Retina kept in place by the

Vitreous humor

Lacriminal glands

Within the orbits, secretes tears

Iris

a ring of muscle tissue that forms the colored portion of the eye around the pupil and controls the size of the pupil opening, has two layers of smooth muscle fibers

macula lutea

a yellowish central area of the retina that is rich in cones and that mediates clear detailed vision

The lens and cornea have no capillaries and are nourished by

aqueous humor

fovea centralis

area of acute or discriminatory vision

Optic disk

area of retina that lacks photoreceptors

anterior cavity of eye

between cornea and lens, filled with aqueous humor

anterior cavity of eye

between cornea and lens, filled with aqueous humor -helps maintain intraocular pressure n imp route for nutrients n waste transport, blackage in circulation o aqueous humor results in glaucoma

posterior chamber of eye

between iris and lens or ciliary body

Posterior cavity

filled with vitreous humor

lacriminal apparatus

group of structures involved in producing and draining tears

Choroid coat

heavily pigmented tunic that prevents light scattering within the eye

Fibrous tunic

provides support/protection, serves as attachment surface for extra-ocular muscles, and has structures to assist in focusing

Muscle that moves eyeball

rectus muscle

Aqueous humor, cornea, lens, vitreous humor

refractory media of the eye

Iris

regulates the size of the pupil

Nervous tunic

retina

Fibrous tunic

sclera and cornea

suspensory ligaments

secures the lens to the ciliary body

Pigmented retina

single layer of cells; filled with melanin. With choroid, enhances visual acuity by isolating individual photoreceptors, reducing light scattering -keeps lite fro being reflected back into eyes

Canal of Schlemm

small veins that reabsorb aqueous humor

Ciliary body and iris

smooth muscle structures (sites of intrinsic eye muscles)

anterior chamber of eye

space between cornea and iris

nasolacrimal duct

takes tears to the nasal cavity

Sclera

the firm white fibrous outer layer of the eyeball; protects and maintains eyeball shape -made of collagen and elastic fibers -thick in back and thin at front -vessels and nerves penetrate to reach organs

vitreous chamber

the main interior portion of the eye, filled with vitreous humor

Cornea

the transparent layer forming the front of the eye. -beneath epithelium is dense matrix made of collagen fibers -no bld vessels, receives oxygen n nutrients fro tears -most sensitive part of eye, lots of nerve endings -damage can cause blindness

Fovea centralis

tiny pit or depression in the retina that is the region of clearest vision -area of greatest visual activity, contains only cone cells

Sclera

white hard part of the eye

Choroid layer

Contains a dark blue pigment to absorb light and prevent glare within the eyeball

Choroid

Contains extensive capillary network delivering oxygen n nutrition to retina, n contains scattered melanocytes

Rods

Contains rhodopsin and detect the presence of light

Myopia

Corrected with concave lens

The white outer tough cn tissue covering of the eyeball

Sclera

Blockage of the whi is suspected in glaucoma?

Scleral venous sinus

aqueous humor

The liquid that fills the anterior section of the eyeball, giving it shape

Choroid

The middle layer of eyeball which contains a black pigment and prevents extraneous light from "reflecting around" inside the eye

Cornea

The transparent part of the sclera layer, it is located on the front surface of the eyeball and aids in focusing light rays as they enter the eye

Cornea

The transparent part of the sclera that reflects light

Hyperopia

A condition in which visual images come to a focus behind the retina of the eye and vision is better for distant than for near objects -- called also farsightedness, coreccting possible w convex lens

vitrous body

A gel-like material that fills the posterior section of the eyeball, giving it shape

Conjunctiva

A thin membrane that lines the eyelids and covers the whites of the eyes

conjunctiva

A thin mucous membrane layer that provides lubrication and covers the cornea and posterior surfaces of the eyelids

Fovea

A very small area on the retina of sharpest focus of incoming light rays

Iris

Colored part of the eyewhich regulated the amount of light entering the eye

Canal of Schlemm

Drains the aqueous humor of the eye

Optic nerve

Exiting at the back of the eye, this structure carries nerve impulses for vision in the brain

Trace the pathway that the secretion of the lacriminal glands takes from the surface of the eye by designing a number to each structure

Lacriminal glands Lacriminal sac Nasolacriminal duct Nasal cavity

Number the proper sequence inolved in process of vision

Light rays➡ Cornea Aqueous humor Lens Vitreous humor Retina Optic nerve

vascular tissue

Middle layer of eye

Extrinsic muscles

Move the eyeball side to side or up and down

Iris

Pigmented "diaphragm" of the eye

Cones

Receptors that detect color

Receptors for vision located in whi pt of eye?

Retina

Rods

Retinal nerve cells sensitive to low levels of light intensity but not to color

Cones

Retinal nerve cells used for color vision

Optic disc

The area of the retina where the optic nerve passes through; no rods or cones are present

Pupil

The hole through which light enters the eye

Retina

The inner layer of the eyeball that's made of light sensitive nerve cells called rods and cones

Retina

The layer of the eyeball which contains visual receptors

Lens

The only adjustable part of the light retracting system

Sclera

The outer layer of the eyeball that provides protection

Fovea

The part of the retina that contains only cones

suspensory ligaments

The structures that hold the lens of the eye in place

Vascular coat of eyeball, deeply pigmented

choroid

Vascular tunic

choroid, ciliary body, iris, pupil

Muscle responsible for altering shape of lens

ciliary muscle

lacriminal apparatus

consists of the lacrimal gland and a series of ducts that drain the tears into the nasal cavity

Eyelids

contain skeletal muscle; spread tears across the front of the eyeball

Vascular tunic

contains most of the blood vessels of the eye and intrinsic eye muscles -provide route for bld vessels regulatin amt o lite entering eye, secretin n absorbin Aquarius humor n controllin shape o lens

Posterior cavity

contains vitreous humor

ciliary body

contracts to change the shape of the lens

Nervous tunic

inner retinal layer made of nervous tissue

Bacterial growth on the front of the eyeball is inhibited by

lysozyme in tears

Ciliary body

muscular structure that manipulates the lens

Choroid coat

nutritive (vascular) tunic of the eye

Fibrous tunic

outer layer of the eye made of cn tissue