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

Plantae, significance of amoebozoa

significance of amoebozoa

Determine the characteristics of soil profile, Characteristics of Soil Prof...

Characteristics of Soil Profile  The profile characteristics studied in the field consist of locating the soil hor izons (based on its colour description that includes the  col

Define role of lipids in controlling gene expression, Define role of Lipids...

Define role of Lipids in Controlling Gene Expression? In the lipogenic pathway, the genes that encode the enzymes of the fatty acid synthase complex are co-ordinately expressed

Protist, Members of phylum animal like protist that are only free living

Members of phylum animal like protist that are only free living

Define some usual doubts of children related to food, Define some Usual Dou...

Define some Usual Doubts of Children related to Food? Before embarking yourself to go through this unit, here is an activity for you to perform, Talk to 2-3 school' boys and gi

Define precaution-estimation of nitrogen and protein content, Define Precau...

Define Precautions - Estimation of Nitrogen and Protein Content? 1. The apparatus should be airtight to prevent leakage of NH 3 . 2. The tip of the delivery tube should be i

What is the spinal cord, What is the spinal cord? Of which elements is the ...

What is the spinal cord? Of which elements is the spinal cord constituted? The spinal cord is the dorsal neural cord of vertebrates. It is the kind of the central nervous syste

Developmental biology, pioneers of developmental biology and their contribu...

pioneers of developmental biology and their contribution

Surgical treatment of infective endocarditis, Cardiac surgical intervention...

Cardiac surgical intervention has an increasingly important role in the treatment of intracardiac complications of endocarditis. Retrospective data suggest that mortality is unacce

Define advantages for underwater weighing method, Define Advantages for und...

Define Advantages for underwater weighing method? This method is currently considered the "gold standard in percent body fat measurement (with the coming up of DEXA, the de

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