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

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

What are the main negative ions found in living beings, What are the main n...

What are the main negative ions found in living beings? The major anions found in living beings are the chlorine anion (Cl-), the phosphate anion (PO4--), the bicarbonate anion

How to recognition of congenital heart disease, How to Recognition of Conge...

How to Recognition of Congenital Heart Disease ? The manifestations of CE-ID are different in a neonate, an infant or a child. It is often easy to recognise the presence of CHD

Explain antioxidants, Antioxidants  Antioxidants are the substances tha...

Antioxidants  Antioxidants are the substances that can delay onset, or  slow the rate of oxidation of autoxidizable materials. By virtue of this property,  they provide protect

Digestive system, describe the effects of the failure of the pancreas to pr...

describe the effects of the failure of the pancreas to produce sufficient insulin

Deficiency diseases-evaluation of production diseases, Evaluation of produc...

Evaluation of production diseases Generally, production diseases are acute states and respond dramatically to administration of a deficient nutrient or metabolite. The nutriti

What are the physiological systems, What are the physiological systems know...

What are the physiological systems known as integrative systems? Why is this designation justified? The integrative systems are the nervous system and the endocrine system. The

Symbolising and language skills, Language, a powerful tool for communicatio...

Language, a powerful tool for communication should have played a very important part in the evolutionary history of human species. Two relevant questions that could be asked of hum

Differentiate between glycogenesis and glycogenolysis, Differentiate betwee...

Differentiate between glycogenesis and glycogenolysis. The synthesis  of glycogen in liver and muscle  is  called glycogenesis.  The breakdown of glycogen in the liver (glycoge

Available and non-available water, Available and Non-available Water Yo...

Available and Non-available Water You have seen above that water is present even in the apparently dry soils but it is of not much use as far as the plants are concerned. They

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