the eyes

• the peripheral organ of vision, is situated in a

  skeletal cavity, the orbit?

  eyeball
• 1 inch in diameter, 8g. in

  weight?

  eyeball
• The eyeball is embedded in?

  orbital fat
• anterior cavity contains?

  aqueous humor
• posterior cavity is located behind the?

  lens
• posterior cavity contains the?

  vitreous humor
• layers of eyeball?

  fibrous coat, vascular coat, neural coat
• under the fibrous coat?

  sclera and cornea
• under the vascular coat?

  choroid, ciliary body, and iris
• under the neural coat?

  retina
• this helps to maintain the shape of the eye?

  sclera
• sclera provide passageways for nerves of the?

  cornea
• this isit is the anterior, projecting transparent part of the external tunic?

  cornea
• cornea is the major site of?

  refraction of light entering the eye
• this is a thin, highly vascular, dark brown tissue which lines almost the posterior five sixths of the eye?

  choroid
• the choroid is pierced behind by the?

  optic nerve
• it is thicker posteriorly?

  choroid
• choroid is also attached to the retinal pigmented layer?

  true
• this is directly continuous with the choroid behind and with the iris in front?

  ciliary body
• Internally it shows a scalloped periphery where

  it is continuous with the choroid and retina, termed the?

  ora serrata
• ciliry body is the major source of?

  aqueou fluid
• is an adjustable diaphragm around a central aperture ?

  iris
• this controls the amount of light entering the eye?

  pupil
• determining the hue of the iris, the main factor is the concentration of?

  melanocytes
• the muscles of the iris?

  sphincter pupillae, dilator pupillae
• this is a flat annulus of smooth muscle about 0.72mm wide and 0.15mm thick?

  sphincter pupillae
• Its densely packed fusiform myocytes are often arranged in small bundles, as in the?

  ciliary muscle
• thin stratum lying immediately anterior to the epithelium of the posterior iridial surface?

  dilator pupillae
• this muscle fibers are in fact the muscular processes of the anterior layer of this epithelium?

  dilator pupillae
• this is the neural, sensory stratum of the eyeball?

  retina
• retina is thin and being thickest near the?

  optic disc
• retina contains a variety of cell types include?

  photoreceptors (rod and cone cells)
• center of the retina is?

  macula lutea
• and the central depression is, where visual resolution is the highest?


  fovea centralis
• chiefly responsible for high spatial resolution and colour vision in good lighting conditions (photopic vision)?

  cone cells
• this is highly concentrated at the fovea centralis, but they populate the whole retina, intermingled with rods?

  cone cells
• under cone cell there is three types, according to their maximum spectral

  sensitivities?

  red, green, and blue
• provide high monochromatic sensitivity to a much wider range of illumination down to much lower intensities (scotopic vision) a?


  Rod cells
• this are excluded from the fovea?

  rod cells
• This region, where retinal tissues meet the neural elements of the optic nerve?

  optic disc