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

Molluscs., what are the economic and ecological importance of molluscs

what are the economic and ecological importance of molluscs

State the types of bone density, State the types of bone density Misch ...

State the types of bone density Misch classified bone density into following types (1988) D1. Dense cortical bone- which is almost never observed in maxilla and approximatel

Parasternal position, Examination is begun by placing the transducer in l...

Examination is begun by placing the transducer in left parasternal region, usually in the third or fourth left intercostal space. From this position, a sector image of the heart

Zoology, explain in detail various types of epithelial tissue

explain in detail various types of epithelial tissue

Special anatomic considerations in posterior maxilla, What are the special ...

What are the special anatomic considerations in posterior maxilla?  Posterior maxilla has very poor  quality of bone demanding special consideration in implant placement. These

Define the glucose tolerance test, Q. Define the Glucose Tolerance Test? ...

Q. Define the Glucose Tolerance Test? In Glucose Tolerance Test (GTT) if the blood sample is to be taken in the morning, patient is advised to follow fasting instructions i.e.

Bacterial diseases-actinomyces, Actinomyces Members of the genus Actin...

Actinomyces Members of the genus Actinomyces are facultative anerobic, gram-positive, non acid-fast, non-spore forming, nonhaemolytic rods. All Actinomyces require rich media

Management of hypertension, Q. Management of hypertension? the manageme...

Q. Management of hypertension? the management of hypertension, angina pectoris and myocardial infarction. It must be clear to you that some aspects of dietary management may di

Define the need for classification of plants and animals, Define the Need f...

Define the Need for classification of Plants and Animals? First of all there is a need to know what classification is? Let us define in simple term. Classification is placing o

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