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

What is mean by stability study, Stability studies are req. for the product...

Stability studies are req. for the product stable at their desire time as per specification , which give the expiry date and quality as per the manner.

What is short bowel syndrome, Q. What is Short Bowel Syndrome? Short bo...

Q. What is Short Bowel Syndrome? Short bowel syndrome is a group of problems affecting people who have /had half or more of their small intestine removed. The massive resection

An mrna molecule codifies only one type of protein, An mRNA molecule codifi...

An mRNA molecule codifies only one type of protein? Eukaryotic cells have monocistronic mRNA, i.e., every mRNA codifies only one polypeptide chain. Prokaryotes can present poly

How is gas exchange done in flatworms, How is gas exchange done in flatworm...

How is gas exchange done in flatworms? Platyhelminthes exchange gases exclusively by diffusion by their body surface. This is only possible because all cells are localized rela

Gene recombinations, Which of the recombination process(transformation, con...

Which of the recombination process(transformation, conjugation and transduction) would be most likely to occur in the natural environment?

Humans have selectively bred many radically, Humans have selectively bred m...

Humans have selectively bred many radically different domestic animals(e.g., St. Bernard and Chihuahua dog breeds). Does this activity result in evolution? why or why not?

Protein requirement in chronic diarrhoea, Q. Protein Requirement in chronic...

Q. Protein Requirement in chronic diarrhoea? Requirements are increased only in chronic diarrhoea because of associated tissue depletion. An additional 10 g of protein may be r

Procedures for diagnosis - epidemiological data , Procedures for diagnosis ...

Procedures for diagnosis Epidemiological data:   The epidemiological information with regard to the history, symptoms, morbidity, mortality, seasonality, age, sex, breed and spe

Strobilation - types of asexual reproduction, Strobilation - Types of Asexu...

Strobilation - Types of Asexual Reproduction Strobilation is a type of asexual reproduction in which successive segments are separated off from the body one after other. It is

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