Sheep Eye Dissection

Purpose of this Lab: To review the structure and function of the eye and to dissect a mammalian eyeball. Eye Labeling: Correct identify each structure labeled below in the picture. Structure A Choroid coat Structure B Retina Structure C Vitreous humor Structure D Sclera Structure E Cornea Structure F Pupil Structure G Lens Structure H Iris Structure I Optic nerve Eye Muscle Labeling: Correctly identify each extrinsic eye muscle labeled in the picture below. Structure A Inferior Rectus Muscle Structure B Inferior Oblique Muscle Structure C Superior Oblique Muscle Structure D Superior Rectus Muscle Structure E Lateral Rectus Muscle Lacrimal Apparatus Labeling: Label the structures of the lacrimal apparatus shown in the picture below. Structure A Lacrimal sac Structure B Lacrimal gland Structure C Excretory ducts of lacrimal gland Structure D Inferior canaliculi Structure E Nasolacrimal duct Which of the following shows the correct order of the structures and fluids through which light passes as it travels through the eye? Cornea -> Aqueous humor -> Lens -> Pupil -> Vitreous humor -> Retina Cornea -> Aqueous humor -> Pupil -> Lens -> Vitreous humor -> Retina Retina -> Vitreous humor -> Lens -> Aqueous humor -> Cornea Cornea -> Vitreous humor -> Pupil -> Lens -> Aqueous humor -> Retina What is the difference between rods and cones? Rods are long and thin; Cones are short and blunt Rods do colorless vision; Cones do color vision Rods show general outlines (shapes); Cones show very sharp, detailed images All of the above are true Which layer of the eye was the most difficult to cut during the dissection? Cornea Sclera Lens Optic nerve What type of tissue is responsible for the toughness of the sclera? Loose connective (areolar) Adipose Vascular Dense connective Where in the eye is aqueous humor located? In the anterior cavity In the posterior cavity In the lens In the choroid coat How do you compare the shape of the sheep's pupil with your own pupil? Your pupil is oval; the sheep's pupil is round Your pupil is round; the sheep's pupil is oval Both your pupil and the sheep's pupils are round Both your pupil and the sheep's pupils are oval What is the function of the choroid coat in the eye? To help the refraction of light waves To help maintain the spherical shape of the eyeball To absorb excess light; keep the inside of the eye dark To hold photoreceptors; send nerve impulses to the brain What eye structure controls the amount of light entering the inside of the eye? Cornea Retina Iris Pupil Dissection Eye Labeling: Identify each eye part labeled in the picture below. Structure 1 Cornea Structure 2 Sclera Structure 3 Optic Nerve Structure 4 Iris Structure 5 Pupil Structure 7 Ciliary Body Structure 8 Choroid Coat Structure 9 Tapetum Lucidum Structure 10 Retina Structure 11 Lens Structure 12 Vitreous Humor