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

Polyembryony, what are the types of polyembryony?

what are the types of polyembryony?

Man-made disasters- chemical disasters, Chemical disasters arise from harm...

Chemical disasters arise from harmful and potentially hazardous chemicals, which if released of misused can pose a threat to the environmental. Its range depends upon military and

What property of the dna fragments permits this separation, DNA can be divi...

DNA can be divide into fragments using restriction enzymes.    (a) Outline the technique used to separate these fragments.    (b) What property of the DNA f

Locomotion in annelida, Locomotion in Annelida Before we discuss the ...

Locomotion in Annelida Before we discuss the details of locomotion in annelids, we have to recapitulate the major subdivisions of the phylum Annelida. Phylum Annelida contain

Describe cytokinesis in a plant cell, Describe cytokinesis in a plant cell....

Describe cytokinesis in a plant cell. Vesicles produced by the Golgi apparatus fuse at  the midline of the cell to form the cell plate, a  cell wall that elongates to divide th

Describe class ophiuroidea in general way, Describe Class Ophiuroidea in ge...

Describe Class Ophiuroidea in general way? Brittle stars have a central disc with five long, thin, flexible arms that can be detached from the body at will in times of danger.

Deficiency diseases-rickets, Rickets Rickets is a complex mineral defic...

Rickets Rickets is a complex mineral deficiency disease of young, growing animals. It is characterized by defective mineralization of growing bones, persistence of hypertrophic

Explain texturization - function of protein, Texturization       Protei...

Texturization       Proteins  constitute the basis of structures and texture  in several foods, whether these come from living tissue  (myofibrills in  meat or fish) or from fa

Define stress factors - etiological risk factors in cancer, Define Stress F...

Define Stress Factors - Etiological Risk Factors in Cancer? Emotions playing a part in malignancy are not a new idea. But these relationships are extremely difficult to measure

The social environment - stress of hospitalization, The Social Environment ...

The Social Environment   When the child is admitted to the hospital his social environment is totally changed and all health team members are strangers for him. It is your resp

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