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

Biotechnology, Determine sequence weights for the sequences ACTA, ACTT, CGT...

Determine sequence weights for the sequences ACTA, ACTT, CGTT, and AGAT in problem 1 by using Thompson, Higgins, and Gibson method a) compute pairwise distances between sequences

Multiple alleles, MULTIPLE ALLELES (i)         More than two alternativ...

MULTIPLE ALLELES (i)         More than two alternative forms (alleles) of a gene in a population occupying the same locus on a chromosome or its homologue are known as multiple

What are imago and nymph, Q. What are imago and nymph? Nymphs are larva...

Q. What are imago and nymph? Nymphs are larvae of hemimetabolic insects (like grasshoppers). They are very similar to the adult insect although smaller, In holometabolic insect

Explain classification of lipids, Classification of lipids  A general c...

Classification of lipids  A general classification of lipids based on their structural components is presented in table. Such a classification, however, is possibly too rigid f

Dna primer, what is the function of dna primer

what is the function of dna primer

What is aflatoxin, Q. What is Aflatoxin? Aflatoxins are the most widely...

Q. What is Aflatoxin? Aflatoxins are the most widely studied of all mycotoxins. Knowledge of their existence dates from 1960, when more than 100,000 turkey died in England afte

Amino acid sequence, Amino acid sequence  is also known as the primary stru...

Amino acid sequence  is also known as the primary structure of a protein/polypeptide; the series of amino acids in a protein/polypeptide controlled by the series of DNA bases.

What are the major cells of which poriferans are made, Q What are the major...

Q What are the major cells of which poriferans are made? Sponges have their external wall covered by flat cells called pinacocytes and having pores well-delimited by special ce

Explain acid butt - carbohydrate utilization pattern test, Acid butt - carb...

Acid butt - carbohydrate utilization pattern test ? Acid butt (yellow) and acid slant (yellow) with or without gas production – Glucose along with lactose and/or sucrose, is deg

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