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

Acute complications of diabetes, Q. Show Acute Complications of Diabetes? ...

Q. Show Acute Complications of Diabetes? Acute complications of diabetes include: Hypoglycemia or low blood sugar: The most frequent cause of low blood sugar is poor timing

Water pollutants - water pollution, Water Pollutants - Water Pollution ...

Water Pollutants - Water Pollution Water pollution can occur on account of any one or more of the following agents: 1. Biological: Pathogens such as virus, bacteria,

Define precaution-estimation of nitrogen and protein content, Define Precau...

Define Precautions - Estimation of Nitrogen and Protein Content? 1. The apparatus should be airtight to prevent leakage of NH 3 . 2. The tip of the delivery tube should be i

Explain the penicillium - fungi, Explain the Penicillium - Fungi? Class...

Explain the Penicillium - Fungi? Classification Kingdom - Mycetae Division - Amastigomycota Class - Ascomycetes Subclass - Plectomycetidae Order - Eurotiales

Important aspects of nutritional needs during emergency, Define important a...

Define important aspects of nutritional needs during emergency situations? This unit discussed important aspects of nutritional needs during emergency situations and under envi

Illustrate wild life sanctuaries, Q. Illustrate Wild Life Sanctuaries? ...

Q. Illustrate Wild Life Sanctuaries? You must have seen how some of the parks are fenced. The intention is to keep the animals from wandering out and not to destroy neighbourin

Which are plant tissues that form the plant roots, Which are plant tissues ...

Which are plant tissues that form the plant roots? Roots have a central portion called medulla made of vascular tissue outer phloem and inner xylem. Medulla is delimited by per

Determine the lateral cephalometric skull view, Determine the Lateral Cepha...

Determine the Lateral Cephalometric Skull View The use of this modality is limited in preoperative evaluation in implant placement for advance cases where there is a need for b

How temperature affect the rate of cellular respiration, How does temperatu...

How does temperature affect the rate of cellular respiration? Please explain with great detail!

Concentration gradient and passive and active transport, Q. What is the rel...

Q. What is the relationship between concentration gradient and passive and active transport? Passive transport is the movement of substances across membranes in favour of their

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