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

Describe the features common in ventricular outflow, Describe the Features ...

Describe the Features common in ventricular outflow obstruction ? An ejection systolic murmur (ESM) due turbulent flow of blood through the obstruction. Hypertrophy of the cham

Female accessory sex organs, Normal 0 false false false ...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

What are the problems that vertebrates required, What are the problems that...

What are the problems that vertebrates required to solve to adapt to the terrestrial environment as they came from the aquatic habitat? How evolution does solve those problems?

Explain the appearance of a single e. coli colony, Describe the appearance ...

Describe the appearance of a single E. coli colony. Why can it be considered genetically homogenous?

Which statement about asexual reproduction is false, Which statement below ...

Which statement below about asexual reproduction is FALSE? a.With asexual reproduction, offspring are genetically identical to the parent. b.Asexual reproduction requires no

Prawn, explain excretory system of prawn?

explain excretory system of prawn?

Alcoholic fermenting organisms used in bread and cake, Q. Why in bread and ...

Q. Why in bread and cake manufacture are alcoholic fermenting organisms used and not lactic fermenting organisms? Fermentation has the function of making breads and cakes grow

Do sea urchins have teeth, Do sea urchins have teeth? Sea urchins have ...

Do sea urchins have teeth? Sea urchins have a teeth-like structure juxtaposed to the mouth and made of five teeth linked to ossicles and muscle fibers. This structure, called a

Define drug effects on metabolism of dietary components, Define Drug effect...

Define Drug effects on Metabolism of dietary components? Drugs can also compete with, or inhibit, the metabolic conversion of some micronutrients to their active metabolites,

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