Eyeball - choroid, Biology

Assignment Help:

CHOROID -

  • Thin, net like made up of connective tissue, rich in blood vessels.
  • Pigment present, red in rabbit, brown or black in man. It reduces internal reflection.
  • Except cornea this layer is attached to sclerotic.
  • In front of cornea this layer froms a thin coloured partition i.e. iris. IRIS -
  • It is perforated in the middle by an aperture pupil. Iris is highly muscular
  • Circular and radial muscles are present. Circular muscles are sphincter type. Radial muscles are dilator type.
  • On contraction of circular muscles diameter of pupil is reduced it is myosis, it takes place in sharp light.
  • On contraction of radial muscles diameter of pupil is increased, it is mydriosis, it occurs in dimlight.
  • Atropine is used to dialate pupil.

2037_choroid.png

  • Basal part of iris is highly muscular having circular, radial and obligue muscles. It is known as cilliary body.
  • On its free surface 70 - 80 cilliary processes present secretes aquous humour in aquous chamber.
  • Cilliary body also affects convexity of lens.

1261_choroid1.png


Related Discussions:- Eyeball - choroid

Define the protective of vitamin c role as an antioxidant, Define the Prote...

Define the Protective of Vitamin C role as an antioxidant? Vitamin C is a powerful antioxidant because it can donate a hydrogen atom and form a relatively stable ascorbyl free

Phylogeny, why do i do it for class/

why do i do it for class/

What are the symptoms of mitral stenosis, Q. What are the Symptoms of Mitra...

Q. What are the Symptoms of Mitral stenosis? The cardinal symptom of mitral stenosis is dyspnoea on exertion. Typically it progresses over a period of years. As the severity in

What are the processes that autotrophic beings, What are the processes that...

What are the processes that autotrophic beings use to produce organic material from inorganic substances? The Autotrophic beings make organic material by photosynthesis or by c

Define integrity of epithelial tissues, Define Integrity of Epithelial Tiss...

Define Integrity of Epithelial Tissues? Vitamin A is essential for the integrity of the mucous-secreting cells. In fact vitamin A maintains the health of epithelial cells that

Effect of alcoholic beverage, Q. Why does the urinary volume increase when ...

Q. Why does the urinary volume increase when alcoholic beverages are ingested? Alcohol inhibits the ADH (antidiuretic hormone) secretion by the hypophysis and Low ADH reduces t

Free racials, Which of the following could potentially be a free radical? A...

Which of the following could potentially be a free radical? Answer oxygen (atomic number 8) helium (atomic number 2) neon (atomic number 10)

Hiv, The chances of transmission in female is mor than males

The chances of transmission in female is mor than males

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd