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

Oncogene, Oncogene is the gene in a tumor virus or in the cancerous cells ...

Oncogene is the gene in a tumor virus or in the cancerous cells which, when transferred into the other cells, can cause the transformation (note which only certain cells are susce

Describe respiratory system , Describe Respiratory System? The respirat...

Describe Respiratory System? The respiratory system is responsible for the transport of oxygen and carbon dioxide from outside the body to and from the blood. This process is c

Circulatory system in cockroach, CIRCUL A T O R Y SYSTEM IN COCKROACH ...

CIRCUL A T O R Y SYSTEM IN COCKROACH Type is open or lacunar. i.e. b.v. absent. Organs are dipped in haemolymph. 1 .      HAEMOLYMPH - Blood and lymph are mixed.

Vitamin, fish liver oil is rich in which vitamin ???

fish liver oil is rich in which vitamin ???

How can you describe pleural effusion, Q. How can you describe Pleural Effu...

Q. How can you describe Pleural Effusion? Fluid has a density indistinguishable from soft tissue on a radiograph. Pleural fluid tends to accumulate in the deepest part of the

Explain the chemical methods for control of microorganisms, Explain the Che...

Explain the Chemical Methods for Control of Microorganisms? Different chemicals can be used which can act as disinfectant, antiseptics or even chemical sterilants. These are:

biodegrade xenobiotic compounds , Xenobiotic compounds are man-made chemi...

Xenobiotic compounds are man-made chemicals that are present in the environment at unnaturally high concentrations. The xenobiotic compounds are either not produced naturally, o

Where does hematopoiesis occur, Where does hematopoiesis occur? Hematop...

Where does hematopoiesis occur? Hematopoiesis happens in the bone marrow (mainly within flat bones), where erythrocytes, leukocytes and platelets are made, and in the lymphoid

Define the thin and thick filaments of a sarcomere, When the overlap betwee...

When the overlap between the thin and thick filaments of a sarcomere in a skeletal muscle is decreasing, A. the total length of the I band is increasing in the sarcomere. B.

Locomotion in octopus, LOCOMOTIO N IN OCTOPUS - From the ends of arms ...

LOCOMOTIO N IN OCTOPUS - From the ends of arms or ex-current siphon water is throughn with speed, opposite to it animal moves.

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