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

Role of fat or lipids in metabolism, ROLE OF FAT OR LIPIDS - Made up...

ROLE OF FAT OR LIPIDS - Made up of fatty acids & glycerol. Linked by ester bond. Maximum quantity of energy is librated. Helpful in temperature regulation. As stored f

Which type of ecological interaction is competition, What is competition? W...

What is competition? Which type of ecological interaction is competition? Competition is the ecological interaction in which the individuals explore the similar ecological nich

Types of cardiac dopler, There are two types of Doppler examination: 1) ...

There are two types of Doppler examination: 1)  Pulse wave Doppler 2)  Continuous wave Doppler Both these modalities are necessary part of Doppler echocardiography and pro

ZOLOGY, The destruction of the ozone layer may be responsible for an increa...

The destruction of the ozone layer may be responsible for an increase in

Define criteria for assessment of riboflavin status, Define Criteria for As...

Define Criteria for Assessment of Riboflavin Status? Riboflavin status can be assessed by measuring urinary excretion of the vitamin in fasting, random, and 24-hour specimens o

Agro-industrial byproducts, Agro-industrial byproducts Agro-industrial...

Agro-industrial byproducts Agro-industrial by-products in Southeast Asia are available in plenty, due to the emphasis on crop cultivation. By-products of agro-industries repre

How is a prototype drug different from other drugs, How is a prototype drug...

How is a prototype drug different from other drugs in the same class?

Byproducts of low digestibility and low nitrogen, Byproducts of low digesti...

Byproducts of low digestibility and low nitrogen Straws, husks, pods and haulms are the byproducts of this category. Very often the nitrogen content in these byproducts is so l

How sugar is used in icings, How sugar is used in Icings? Sugars provid...

How sugar is used in Icings? Sugars provide sweetness, flavor, bulk and structure to icings and frostings. In addition to sweetness and flavor, icings also function as a barrie

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