Microanatomy Special Senses

Eyes, Ears

What embryonic layer do the lens, outer corneal epithelium, and eyelid epithelium come from

Ectoderm

What embryonic origin do the corneal stroma, sclera, extraocular muscles, ciliary muscles, and tunica vasculosa come from

Mesoderm

What forms the optic cup

Neuroectoderm of diencephalon

What are the 2 layers of the optic cup

Retina

Pigment epithelium

What is the name of the bony socket of the skull where the eye sits

Orbit

What is another name for the eyeball

Globe

The eye is composed of a lens and what 3 layers

Outer fibrous tunic

Middle vascular (uveal) tunic

Inner retinal (neuroepithelial) tunic

Accessory ocular structures are also called

The adnexa

What structures are considered part of the adnexa

Palpebrae (eyelids), third eyelid and conjunctiva, and lacrimal apparatus

Which tunic includes the sclera and cornea

Fibrous tunic

Which tunic of the eye includes the iris, ciliary body, and choroid

Vascular tunic

Which tunic of the eye includes the pigmented layer and neural layer

Neuroepithelial (retinal) tunic

What are the functions of the sclera

Protect the eye

Maintain eye shape

Insertion points for tendons of extraocular muscles

The sclera is a white opaque layer of ____ (dense vs loose) ______ (regular vs irregular) connective tissue

Dense irregular

Sclera is found on anterior or posterior portion of eye

Posterior

The cornea is found on the anterior or posterior portion of the eye

Anterior

T/F: the cornea is vascular and transparent

False

It IS transparent, but it is avascular

Why is the cornea relatively dehydrated

To maintain transparency

T/F: the corneal epithelium has good regenerative capacity

True

What are the cornea layers from outermost to innermost

Anterior epithelium

Anterior limiting membrane / basal layer of anterior epithelium

Substantia propria

Posterior limiting membrane / Descemet’s membrane

Posterior epithelium / corneal endothelium