Nervous system - meninges, Biology

Assignment Help:

Meninges (Singular-Meninx) -

  • Ceverings of brain.
  • By infection in meninges meningitis or brain fever is caused.
  • These menings are internally lined by squamous epithelium and of following types -

(i) Duramatter - Outer thick, fibrous attached to inner part of cranium i.e. Endorachis.

(ii) Arachnoid - Middle layer of meninges. Net like in appearance. Made up of squamous epitelium.

(iii) Piamatter - Inner most layer, thin, membranous, blood vessel present. Gives nourishment to brain. This layer enters into dorsal wall of brain & form choroid plexus or tella choroidea. In man choroid plexus are 5 (2 in lateral ventricle, 2 in 3rd ventricle & 1 in 4th ventricle) in rabbit choroid plexus are 2 (1 in dianchephalon & 2nd in medulla oblongeta).

  • Choroid plexus is responsible to form C.S.F. (cerebrospinal fluid). CSF is formed 20 ml/hr.

Note :- Arachnoid and piamatter are collectively known as leptomeninges.

  • In fishes meninx is menias premitiva. In amphibia arachnoid is absent.
  • Between meninges sub dural & sub arachnoid spaces are present filled with little CSF.

2272_meninges.png

MENINGES


Related Discussions:- Nervous system - meninges

Explain about freezing point - properties of solutions, Freezing Point - Pr...

Freezing Point - Properties of Solutions The freezing point of a material is the temperature at which it changes from a liquid to a solid. A liquid freezes when its vapour pre

Diabetes mellitus, 1. How often should she have Glycated hemoglobin (HgbA1C...

1. How often should she have Glycated hemoglobin (HgbA1C) drawn?  What percentage is desired? 2. How often should she see an ophthalmologist or optometrist? 3. What should be

An experiment with a floating egg, An experiment with a floating egg Pl...

An experiment with a floating egg Place an egg in a glass of fresh water and view it. Next add salt to the water and see if you can float the egg. How does this relate to the f

Ultrasonic removal of gutta percha, Ultrasonic removal of Gutta percha: ...

Ultrasonic removal of Gutta percha: -the piezoelestic ultrasonic system. - As the instruments is energized; producing heat to themosoften gutta-percha. - Float gutta-perc

How different are animal cells from plant cells, How different are animal c...

How different are animal cells from plant cells? Whereas plant cells are eukaryotic, autotrophic, photosynthetic and have chloroplasts and cell wall, the animal cells are eukar

What is commensalism, Q. What is commensalism? The Commensalism is the ...

Q. What is commensalism? The Commensalism is the ecological interaction in which one individual benefits while the other is neither benefited nor harmed. The Commensalism is a

Excretory system, what is the excretory organ of agama lizard

what is the excretory organ of agama lizard

Types specimens of echpnodermata, Types specimens of echpnodermata Befor...

Types specimens of echpnodermata Before we begin the study of the selected specimens of the following echinoderms - Feather star, Brittle star, Sea urchin, Sea cucumber and Star

What are the cnidocytes, Q. What are the cnidocytes? What is the name of th...

Q. What are the cnidocytes? What is the name of the capsule inside the cnidocyte? What are the biological functions of this structure? Cnidocytes are specific cells present in

What are the advantages of yoga, What are the advantages of Yoga Yoga h...

What are the advantages of Yoga Yoga has been derived from the Sanskrit word Yuj which means union. It is popular since ancient times. It is also one of the means to maintain f

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