Lab Practical Final (2025)

Superior Rectus

Moves eye upwards

Inferior Rectus

Moves eye downwards

Lateral Rectus

Moves eye laterally (to ears)

Medial Rectus

Moves eyes medially (to nose)

Superior Oblique

Moves the eye both downward and laterally

Inferior Oblique

Moves the eye both upward & laterally

Accessory structures of the eye

protect the eyeball, no role in vision

-eyebrows, eyelashes, upper and lower eyelids, conjunctiva, lacrimal apparatus, extrinsic eye muscles

Eyebrows (accessory structures of the eye)

superior to each orbit, act as partial filters. They protect our eyes from sweat and sunlight

Upper and lower eyelids (palpebrae)

Protects our eyes from bright lights and foreign objects. shades our eyes during sleep and lubricates the eyeballs by spreading lubrication around from mucous membranes

Eyelashes

They help protect our eyes from foreign objects, sweat, and sunlight

Conjunctive

Thin mucous membranes covering the inner wall of the eyelid and the anterior eye surface.

It keeps the front surface of the eyelids moist.

Lacrimal apparatus

produces and drains tears

-lacrimal gland

-lacrimal canals

-lacrimal sac

- nasolacrimal duct

Lacrimal gland

produce and drain tears into the eye. (#3 on picture)

Lacrimal sac and lacrimal duct

drains into the eye. (#1 on picture)

nasolacrimal duct

drains into the nasal cavity. (# 5 on picture)

lacrimal canals (canaliculi)

Drain tears from at medial side of the eyes into the lacrimal sac. (#2 on the picture)

Sclera

The white of the eye. A coat of dense connective tissue that adds to the shape of the eye and provides protection of the internal eye structures.

Cornea

The anterior most portion of the sclera. It appears cloudy in preserved specimens. The cornea is the first portion of the eye to receive light.

Optic nerve

Cranial nerve II can be seen exiting the back of the eye en route to the brain. This nerve carries information regarding visual stimuli to the occipital lobe.

Ciliary body

A black pigmented body that appears as a halo encircling the lens. It consists of mostly muscle for controlling the tension of the suspensory ligaments. The ciliary body also secretes the aqueous humor that circulates in the anterior cavity of the eye.

Lens

A biconvex structure that is hard and opaque in preserved specimens. The shape of the lens determines where light will be focused on the retina.

Suspensory ligaments

A halo of delicate fibers attaching the lens to the ciliary body. A change in the tension of the suspensory ligaments will alter the shape of the lens and affect the focusing of light on the retina.

Iris

Anterior continuation of the ciliary body penetrated by the pupil. This portion of the eye gives the eye its color.

Choroid

Posterior continuation of the ciliary body. It appears brownish-black in humans, but is iridescent in nocturnal animals (tapetum lucidum).

Retina

Delicate yellowish-white membrane that easily separates from the choroid layer during dissection. The retina contains the photoreceptors necessary for vision. Neurons from sensory cells in the retina exit the eye to form the optic nerve at the optic disc.

Tapetum lucidum (Choroid Coat)

Iridescent layer found in nocturnal animals for maximizing vision under low intensity light

Aqueous humor

The watery liquid secreted by the ciliary body that circulates in the anterior cavity of the eye. The aqueous humor must be drained to avoid an increase in intraocular pressure (glaucoma results from a blockage in the aqueous humor drainage system).

Vitreous humor

A thick, gelatinous substance located in the posterior cavity of the eye behind the lens. This humor helps to maintain the position of the retina against the choroid layer of the eye.

Anterior Cavity

The fluid-filled space inside the eye between the iris and the cornea's innermost surface, the endothelium. Aqueous humor is the clear fluid that fills the anterior chamber.

Posterior chamber of the eye

filled with a watery fluid known as the aqueous humor, or aqueous. Produced by a structure alongside the lens called the ciliary body, the aqueous passes into the posterior chamber and then flows forward through the pupil into the anterior chamber of the eye.

Vitreous Chamber

largest of the three chambers and is located behind the lens and in front of the optic nerve. This chamber is filled with a thick, clear gel-like substance called the vitreous humor (also vitreous body). The humor plays a crucial role in supporting the posterior side of the lens.

Pupil

a hole located in the center of the iris of the eye that allows light to strike the retina. It appears black because light rays entering the pupil are either absorbed by the tissues inside the eye directly, or absorbed after diffuse reflections within the eye that mostly miss exiting the narrow pupil.

Optic Disc

the raised disk on the retina at the point of entry of the optic nerve, lacking visual receptors and so creating a blind spot.

Fovea Centralis

a small depression in the retina of the eye where visual acuity is highest. The center of the field of vision is focused in this region, where retinal cones are particularly concentrated.

Macula Lutea

an oval yellowish area surrounding the fovea near the center of the retina in the eye, which is the region of keenest vision.

Suspensory ligaments of the eye

a series of fibers that connect the ciliary body of the eye with the lens, holding it in place.

Ciliary Body

includes the ciliary muscle, which controls the shape of the lens, and the ciliary epithelium, which produces the aqueous humor. The vitreous humor is produced in the the non-pigmented portion of the ciliary body.

Longitudinal fissure

Frontal lobe

Parietal lobe

Temporal lobe

Occipital lobe

What are sulcus (sulci)?

grooves in the brain

what are gyrus (gyri)?

elevated ridges of the brain

Arachnoid mater

Identify the membrane

Cerebellar hemispheres

Identify the hemisphere G

Superior Colliculi

Inferior Colliculi

Olfactory bulbs

Optic nerves

Optic chiasma

Optic tracts

Infundibulum

Mammillary bodies

Midbrain

Cerebral peduncles

Pons

Medulla oblongata

Spinal cord

Lateral ventricle

Identify the star

Choroid plexus

Fourth Ventricle

Cerebral Aqueduct

Cerebral peduncle

dura mater

Identify the covering.

cerebrum

Identify the major brain region.

cerebellum

Identify the major brain region.

olfactory bulb

Identify the tip.

optic nerve

Identify the nerve by name.

optic tract

Identify the structure.

pituitary gland

Identify the structure.

infundibulum

Identify the structure.

mammillary body

Identify the structure.

cerebral peduncle

Identify the structure.

pons

Identify the structure.

pons

Identify the structure.

medulla oblongata

Identify the structure.

medulla oblongata

Identify the structure.

thalamus

Identify the structure.

hypothalamus

Identify the structure.

corpora quadrigemina

Identify the multi-part structure.

superior colliculus

Identify the structure (dorsal view of midbrain).

superior colliculus

Identify the structure.

inferior colliculus

Identify the structure (dorsal view of midbrain).

inferior colliculus

Identify the structure.

pineal gland

Identify the structure (dorsal view of midbrain).

pineal gland

Identify the structure.

arbor vitae

Identify the branching structure.

corpus collosum

Identify the structure.

fornix

Identify the structure.

septum pellucidum

Identify the membrane.

What is cranial nerve I?

olfactory nerve

What is cranial nerve II?

optic nerve

Identify as many cranial nerves as you can

Check for correction