Medical School Histology Basics Eye

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Medical School Histology Basics Eye

• VIBS 289 lab

• Larry Johnson
  Texas AM University

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OUTLINE
Aqueous humor

• OVERVIEW
• CELLULAR STRUCTURES THROUGH WHICH LIGHT PASSES
• CORNEA
• LENS
• RETINA
• STRUCTURES WHICH INFLUENCE THE IMAGE
• IRIS
• CILIARY BODIES
• TRABECULAR MESHWORK

Vitreous humor
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Aqueous humor
VITREOUS BODY (VITREOUS HUMOR)
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34412
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Eye conjuctiva on white of eye
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sclera
Conjunctiva
Stratified squamous epithelium with some goblet
cells
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Eye 192 human and 34412 monkey
Aqueous humor
Connective tissue
Nerve
Posterior chamber
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Retina
Cornea
Sclera
Pupil
Optic nerve
Anterior chamber
Lens
Iris
34412
Ciliary body
34412
Chorioid layer
Vitreous body
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Eye corneal layers
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Stratified squamous Epithelium
Bowman's membrane
Corneal endothelium
Corneal stroma
Corneal fibroblasts
Descemet's Membrane
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corneal layers Iris of Eye (toluidine blue)
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Ciliary muscle smooth muscle
Sclera
Lens
Sclera-cornea junction (limbus)
Aqueous humor
Bowman's membrane
Corneal stroma
Aqueous humor
Corneal endothelium
Iris
Descemet's Membrane
Iris
Anterior chamber
Posterior chamber
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292 Ciliary muscle smooth muscle
Ciliary processes
Blood vessel
lens
Nerves
Ciliary muscle
192
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Eye ciliary muscle
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Iris
Pupil
Artifactual space
Conjunctival sac
Ciliary muscle
Sclera-cornea junction (limbus)
Posterior chamber
Ciliary processes
Anterior chamber
Ciliary muscle (smooth muscle)
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192 Eye secretory cells
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Pigmented cells of the ciliary processes become
the dilator muscle of the iris
Pigmented cells
Secretory cells
Secretory cells become the pigmented cells of
the iris
Iris
Ciliary processes
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Eye (toluidine blue)
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Conjunctiva
Ciliary muscle
Iris
Trabecular meshwork
Air
Canal of Schlemm
Anterior chamber
Limbus
Endothelium of trabecular meshwork is continuous
with the transport endothelium of the cornea
Ciliary processes
Iris
Posterior chamber
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Eye trabecular meshwork and canal of Schlemm
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Canal of Schlemm
Ciliary muscle
Limbus
Trabecular meshwork
Anterior chamber with aqueous humor
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Canal of Schlemm
Trabecular meshwork
Iris
Blood vessels
Posterior chamber with aqueous humor
Monkey eye
34412
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Eye (toluidine blue)
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Lens
Anterior chamber
Dilator muscle
Lens capsule
Lens
Posterior chamber
Iris
Iris
pupil
Cuboidal epithelium on anterior surface of
lens
Constrictor muscle
Iris
Pupil
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Eye (toluidine blue)
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Lens
Lens cuboidal epithelium
Lens
Lens capsule
Iris constrictor smooth muscle
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The capsule is a shared basement membrane of the
lens epithelium
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The capsule is a shared basement membrane of the
lens epithelium
Lens
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Lens and iris
192 and 34412
Lens anterior surface
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Pigmented epithelium of iris
Iris
Lens capsule
Posterior chamber
Iris
Lens cuboidal epithelium
34412
Iris constrictor muscle is smooth muscle
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Eye (toluidine blue) elongation of lens cuboidal
cells at bow region
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Lens cuboidal epithelium on its anterior surface
gives rise to elongated lens fibers in the bow
region, and the shared basement membrane of these
cells is the capsule
Capsule
Lens cuboidal epithelium
Capsule
flattened lens fibers
No cuboidal epithelium on the posterior surface
of the lens and the capsule is thinner there
Artifactual space
34412
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34412
Anterior surface
Sites of attachment of zonules to the lens
capsule
Eye monkey
Iris
Anterior surface
Posterior surface
Ligaments (zonules)
lens
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One site of attachment of a zonule to the
capsule on the lens on its posterior surface
lens
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34412
Sclara
Ciliary muscle
Zonules
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Lens fibers
Capsule and cuboidal epithelium on the anterior
surface of lens
Thinner capsule on the posterior surface of the
lens
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Eye monkey
34412
Capillary network in retina
Pigmented layer of epithelial cells
Elaborate network of vessels, the choroid
plexus.
Central artery of the retina
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34412
Cones Rods
Ganglion cell layer
Bipolar cells
Vitreous body
Retinal pigmented epithelium
Artifactual space
Photosensitive portion of rod and cone cells
Retinal pigmented epithelium
Artifactual space
Venule in the choroid plexus
Sclera
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Rods
Cones
Photosensitive portion of rod and cone cells
Nuclei of rod and cone cells outer nuclear
layer
Retinal pigmented epithelium
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Eye - Retina and choroid
Blood vessels in the retina
Artifact space
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Choroid
Choroid plexus
Melanin granules
Retina
Nucleus
Retinal pigment epithelium
Optic nerve
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Retina (toluidine blue)
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Bipolar cells
Artifactual space
Photoreceptor cells
Rods
Optic nerve
Cones
Capillary
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Typical retina
Macula with top two layers pulled back to aid
vision
Ganglion cell layer
Bipolar cells
Rods and cones
Rods and cones
Retinal pigmented epithelium
Retinal pigmented epithelium
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Cornea
Conjunctiva
Sclera
lens
Choroid plexus
Cornea
Iris
Sclera
Retina
Vitreous body
Lens
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Anterior chamber
Optic nerve
Posterior chamber
Aqueous humor
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34412
Pigmented epithelium
Blind spot where optic nerve enters the retina
Choroid
Bipolar cell layer
Ganglion cell layer
Photosensitive region of rods and cones
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Eye (toluidine blue)
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Blind spot where optic nerve enters the retina
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34412
Choroid plexus
Retina
OPTIC CUP AND NERVE HEAD
Retina
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In summary
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Questions on the eye

• 1. The integrity of the relationship among
  structures of the eye is produced/maintained by
• supporting layer of the eye holding pressure
• precise regulation of pressure via aqueous humor
  production and outflow
• the bony structure of the sclera in mammals
• a and b
• a, b, and c

2. Which structure is not correctly paired with
its function? a. the iris regulates the amount
of light that reaches the retina b. ciliary
bodies alter the shape of the lens by the
attached zonules c. the trabecular meshwork
enhances the outflow of vitreous humor d. the
cornea focuses the image on the retina e. the
retinal and choroid blood vessels provide
nutrients to the retina
3. Which function(s) least match(s) that of the
cornea? a. protection b. structural support c.
filter out undesirable light rays d. focus image
on photosensitive portion of the photoreceptor
cells e. none of the above
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Many illustrations in these VIBS Histology
YouTube videos were modified from the following
books and sources Many thanks to original
sources!

• Bruce Alberts, et al. 1983. Molecular Biology
  of the Cell. Garland Publishing, Inc., New York,
  NY.
• Bruce Alberts, et al. 1994. Molecular Biology
  of the Cell. Garland Publishing, Inc., New York,
  NY.
• William J. Banks, 1981. Applied Veterinary
  Histology. Williams and Wilkins, Los Angeles,
  CA.
• Hans Elias, et al. 1978. Histology and Human
  Microanatomy. John Wiley and Sons, New York, NY.
• Don W. Fawcett. 1986. Bloom and Fawcett. A
  textbook of histology. W. B. Saunders Company,
  Philadelphia, PA.
• Don W. Fawcett. 1994. Bloom and Fawcett. A
  textbook of histology. Chapman and Hall, New
  York, NY.
• Arthur W. Ham and David H. Cormack. 1979.
  Histology. J. S. Lippincott Company,
  Philadelphia, PA.
• Luis C. Junqueira, et al. 1983. Basic
  Histology. Lange Medical Publications, Los
  Altos, CA.
• L. Carlos Junqueira, et al. 1995. Basic
  Histology. Appleton and Lange, Norwalk, CT.
• L.L. Langley, et al. 1974. Dynamic Anatomy and
  Physiology. McGraw-Hill Book Company, New York,
  NY.
• W.W. Tuttle and Byron A. Schottelius. 1969.
  Textbook of Physiology. The C. V. Mosby Company,
  St. Louis, MO.

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