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

Define translation phase of gene expression process, Define Translation Pha...

Define Translation Phase of gene expression process? The NDA which the transcript into m RNA is translated into protein with the help of ribosomes, m RNA, amino acids, a number

A dihybrid cross yields 320 f2 offspring, A dihybrid cross yields 320 F2 of...

A dihybrid cross yields 320 F2 offspring. How many are expected to resemble the homozygous recessive parental?

Define the term functional foods, Define the term Functional Foods? The...

Define the term Functional Foods? The term 'functional food' was born in Japan. Functional foods are actually products formulated with naturally occurring chemicals or a combin

Define root-end resection apicoectomy, Define Root-End Resection Apicoectom...

Define Root-End Resection Apicoectomy a. Examine the root surface before cutting for: cracks, anatomical variations, and quality of orthograde obturation. b. Cut the root en

Class of subphylum uniramia - pauropoda, Class of Subphylum Uniramia - Paur...

Class of Subphylum Uniramia - Pauropoda A small group of uniramians, there are 500 species of Pauropoda explained so far. The minute organisms computing about 1.5 mm in length

Chuck darwin knew blending theory, Chuck Darwin knew BLENDING THEORY, but h...

Chuck Darwin knew BLENDING THEORY, but he also knew that if it was true his NOT work because

Skeletal system - hyoid bone, HYOI D BONE - Also called tongue bone...

HYOI D BONE - Also called tongue bone as lies at the base of the tonuge. One in number. Muscles of tongue and throat are attached to it. Not e :- Except

Protozoans - regeneration in invertebrates, Protozoans - Regeneration i...

Protozoans - Regeneration in Invertebrates Most single celled animals such as protists, i.e. protozoans, regenerate very well. If part of the cytoplasm is removed from the

How do the sodium and potassium ions maintain the neuron, How do the sodium...

How do the sodium and potassium ions maintain the resting potential of the neuron? The plasma membrane of the neuron when at rest maintains an electric potential difference amo

Explain trypsin, Trypsin Trypsin is secreted in the inactive  form  try...

Trypsin Trypsin is secreted in the inactive  form  trypsinor  -  which is converted into the active form  trypsin by  the enzyme enterokinase secrated by  the duodenal mucosa.

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