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

Genetic diversity of population, Genetic Diversity of Population The b...

Genetic Diversity of Population The biological diversity of animals, plants, and microorganisms is of fundamental importance to human survival. The term "gene resources" may b

Explain assessment of iron status - transferrin receptors, Explain assessme...

Explain assessment of iron status - Transferrin receptors? Transferrin receptors: As iron deficiency progresses into second stage, the number of transferrin receptors on the ce

How different are pteridophytes from bryophytes, Q. How different are pteri...

Q. How different are pteridophytes from bryophytes regarding substance transport? Pteridophytes are tracheophyte (vascular) plants that are they have tissues specialized in con

What is autophagic intracellular digestion?, Autophagic intracellular diges...

Autophagic intracellular digestion is the cellular internal digestion of waste and residual materials. In general it is completed by lysosomes. Autophagic intracellular digestio

Public-private dichotomy in providing health services, Normal 0 ...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

Zoology, Give the salient features of phylum protozoa

Give the salient features of phylum protozoa

Determine the proecss of contrast sense, Contrast sense Sense of contr...

Contrast sense Sense of contrast is the ability to perceive slight changes in luminance between regions which are not separated by definite borders. This is as important as to

What is the meaning of term - plasticity, What is the meaning of term - Pla...

What is the meaning of term - Plasticity The notion of brain plasticity has been of interest to researchers and clinicians alike for decades. The outcome of injury is the resul

What does fungus looks like, Q. What does this fungus looks like? Ans...

Q. What does this fungus looks like? Ans. The important characteristic features of aflatoxicosis are jaundice, cirrhosis. Long term exposure to aflatoxins could lead to

Describe about investigative tools and their optimal use, Describe about In...

Describe about Investigative Tools and their Optimal Use ? The investigative tools that are available for diagnosis of CHD include ECG, chest X-ray, 2D and Doppler echocardiog

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