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

Which starch is being broken down by an enzyme, In an investigation to comp...

In an investigation to compare the rates at which starch is being broken down by an enzyme    (a) what test is used    (b) how do you know when the reaction

Determine the benedict test, Determine the Benedict's Test Glucose in u...

Determine the Benedict's Test Glucose in urine is detected by Benedict's method and the test is known as Benedict's test. This test is used to detect glucose in urine (Glycosur

Financing of healthcare - constraints, Financing of Healthcare - Constraint...

Financing of Healthcare - Constraints One of the major constraints to improve the healthcare delivery system in developing countries is weak public sector management. These ec

Hirschsprungs disease, Hirschsprungs Disease (Congenital Megacolon): T...

Hirschsprungs Disease (Congenital Megacolon): This  is also known as congenital megacolon. There is absence of ganglion cells, submucus plexus  and intramural plexus  (parasym

Define the xtensor motor neurons, Which of the following occur in response ...

Which of the following occur in response to an increase in the length of the right knee extensors in response to a quick tap applied to the right patellar tendon?  An increase in t

Is total volume of the reaction is 30 micro liters, You have a 10x enzyme b...

You have a 10x enzyme buffer that you are to use in a particular reaction. The total volume of the reaction is 30 micro liters. How much of the 10x buffer should you add so that th

Radioactive labelling, Radioactive Labelling Radioactive labelling me...

Radioactive Labelling Radioactive labelling method has been effectively applied on the chick blastoderm. The method includes labelling one embryo (donor) and grafting a part

What is the spontaneous generation hypothesis, What is the spontaneous gene...

What is the spontaneous generation hypothesis? The impulsive generation abiogenesis or hypothesys asserts that life on earth has come from nonliving material. For instance, t

Classification of fishes, Q What are the two major classes into which fishe...

Q What are the two major classes into which fishes are divided? Ans. Fishes are divided into two major classes: osteichthyes, bony fishes (tuna, sardines, salmons) , and chondr

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