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

How dynamic biological processes represented as network, How dynamic biolog...

How dynamic biological processes represented as network? Many dynamic biological processes throughout a wide range of ecological scales are easily represented as dynamical netw

Does ph affect the enzyme activity, Q. Does pH affect the enzyme activity? ...

Q. Does pH affect the enzyme activity? The concentrations of hydrogen ions in solution affect the enzyme activity. Each enzyme has utmost efficiency under an optimum p H . S

What are plant hormones, What are plant hormones? Plant hormones, also ...

What are plant hormones? Plant hormones, also known as phytohormones, are substances that control the embryonic development and the growth of the adult plant.

What are the symptoms causes of fever, During a fever in a human, A. sh...

During a fever in a human, A. shivering can happen when the actual body temperature is higher than the set point for body temperature during the fever. B. the control system

phylum , characters of phylum rynchocephali

characters of phylum rynchocephalia

Phase contrast microscopy, Phase Contrast Microscopy Phase contrast micro...

Phase Contrast Microscopy Phase contrast microscope has the resolving power similar to ordinary light microscope. However, it enables us to observe the cellular organelles in liv

Genetics , Genetics Genetics is the study of heredity. It is an ancien...

Genetics Genetics is the study of heredity. It is an ancient discipline. At least 4000 years ago, in Sumeria, Egypt and other parts of the world, farmers recognized that they

What is the natural habitat of e.coli, What is the natural habitat of E.col...

What is the natural habitat of E.coli? The E.coli was first recognized in the colon region of large intestine and so it was given the name "coli" (found in colon) they are coli

Explain the alterations occurring in meat and poultry, Alterations occurrin...

Alterations occurring in meat and poultry Meat, as you already know, is  rich in proteins and contains most of the essential amino acids.  It is also rich in minerals such as c

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