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 are the consequences of pem, What are the Consequences of PEM? Th...

What are the Consequences of PEM? The consequences of PEM are most often long lasting and irreversible. The common consequences include: • Irreversible growth retardation

Left border of the heart, Connect point A and D by line which is convex to ...

Connect point A and D by line which is convex to the left. The left border is formed by the left ventricle except at its upper end which is formed by the left auricle where there i

What is the life cycle of the schistosome, What is the life cycle of the sc...

What is the life cycle of the schistosome? Male and female adult schistosomes live in blood vessels of the human intestines. The females release eggs that trespass the vessel w

Lower invertebrates, adaptation of the phylum protozoa to its function

adaptation of the phylum protozoa to its function

Define metabolic activity and cell constituents, Define Metabolic Activity ...

Define Metabolic Activity and Cell Constituents? Metabolic activity like amount of acid produced or CO 2 produced is directly proportional to the number of bacteria present, s

Explain functions of proteins, Explain Functions of proteins Functions ...

Explain Functions of proteins Functions of proteins are included herewith. These include: Source of energy: Constituent amino acids can be deaminated and metabolized to

Why is it important for chromosomes to be condensed, Why is it important fo...

Why is it important for chromosomes to be condensed during mitosis and decondensed during interphase? During mitosis the major problem to be solved is the correct separation of

Explain about bioactive materials, Explain about Bioactive materials Bi...

Explain about Bioactive materials Bioactive materials: Certain glasses, ceramics, and glass-ceramics that contain oxides of silicon, sodium, calcium and phosphorus (SiO 2 , Na

Give three examples of artificial selection, Give three examples of artific...

Give three examples of artificial selection. Include examples of both animals and plants.  Answers will vary, but could include domestic cats, domestic dogs, cattle, sheep, an

Briefly explain how amniocentesis used in genetic screening, Briefly explai...

Briefly explain how amniocentesis and chorionic villi sampling are used in genetic screening. A small sample is removed from the amniotic fluid surrounding the fetus or from t

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