Nervous system - spinal nerves, Biology

Assignment Help:

SPINAL NERVES

  • 31 Pairs. Mixed type. Total weight 150 gms.
  • At the base of origin of spinal nerves gland of swammardon or calcarious ganglion is present.
  • Composed of medulated nerve fibres.
  • Classified into five groups -

1. Cervical                          - 8 pairs

 

2. Thoracic                         - 12 pairs

 

3. Lumber                           - 5 pairs

 

4. Sacral                            - 5 pairs

 

5. Coccygeal                      - 1 pair

  • Each spinal nerve is originated from spinal cord from dorsal root and ventral root.
  • In dorsal root, root ganglion is present. Both roots fuse in neural canal to form spinal nerve.
  • It comes out of vertebral column from inter vertebral foramen.
  • Out side vertebral column each spinal nerve is divided into three parts - 

                    (i) Dorsal branch or Ramus dorsalis

                    (ii) Ventral branch or Ramus ventralis

                    (iii) Visceral branch or Ramus communicans

  • Dorsal branch to skin and muscle of dorsal side.
  • Ventral branch to skin & muslce of ventral side.
  • Visceral branch is attached to ganglions of A.N.S.
  • In rabbit 37 pairs spinal nerves present -

1. Cervical                          - 8 pairs

2. Thoracic                         - 12 pairs

3. Lumber                           - 7 pairs

4. Sacral                            - 4 pairs

5. Caudal                           - 6 pairs

In rabbit caudal nerves combine with filum terminalis to form cauda equina.


Related Discussions:- Nervous system - spinal nerves

What is the process of evolution, Why acquired traits are not directly rela...

Why acquired traits are not directly related to the process of evolution? As acquired traits are not genetically determined, they cannot be passed on to offspring. Therefore,

How different are animal cells from plant cells, Q. How different are anima...

Q. How different are animal cells from plant cells? While plant cells are eukaryotic, photosynthetic, autotrophic and have chloroplasts and cell wall, the animal cells are hete

Define mobilization of bone calcium and phosphorous, Define Mobilization of...

Define Mobilization of bone calcium and phosphorous? It is now firmly established that vitamin D 3 is metabloized first in the liver to 25-hydroxyvitamin D (25 OH- D) (calcicl

Flow cytometry, The following histograms were produced using flow cytometry...

The following histograms were produced using flow cytometry after labelling B-cell lymphocytes with propidium iodide. Histogram A is from a healthy individual while Histogram B is

Describe the factors of maintenance of implants, What are the special consi...

What are the special considerations required to be taken in maintenance of implants? The procedures for maintenance of patients with implants are similar to those with natural

Explain the hormonal control of the reproductive system, Explain the hormon...

Explain the hormonal control of the reproductive system in human male. Define totipotency. Verify the two different routes of regenerating plantlets from callus culture.

Simple squamous epithelium - stratified squamous epithelium, Q. How differe...

Q. How different is the simple squamous epithelium from the stratified squamous epithelium? Where can these epithelia are found in the human body? The simple squamous epitheliu

Excretion, What is the excretion for agamalizard

What is the excretion for agamalizard

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