Nervous system - spinal nerves, Biology

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.

Posted Date: 10/3/2012 1:56:47 AM | Location : United States







Related Discussions:- Nervous system - spinal nerves, Assignment Help, Ask Question on Nervous system - spinal nerves, Get Answer, Expert's Help, Nervous system - spinal nerves Discussions

Write discussion on Nervous system - spinal nerves
Your posts are moderated
Related Questions
Q. Explain Femoral Approach? This approach involves the insertion of a catheter over a guidewire i.e. inserted into a sheath in the right femoral artery. Systemic anticoagulati

Define Drug effects on food intake - Cause sore or painful Mouth? This is a common side effect of chemotherapy and can significantly affect food intake. Antineoplastic drugs, u

Q. Carbohydrates requirement during diabetes? Carbohydrates: These to a large extent depend on the food habits. Complex carbohydrates with more fibre are recommended to simple

Clone (verb) is the action of duplicating the genetic material within a vector. To clone the piece of DNA, one would insert it into some type of the vector (like, a plasmid) and p

What about foam stability? Foam stability can be determined by two factors i.e. drainage and bubble size. The volume of the liquid drained due to gravitational forces when foam


List structures found in unicellular organisms that are an adaptation to their free-living life and are not usually found in the cells of multicellular organisms.

Explain about the Cellular senescence - Geriatric Nutrition? Aging brings about an irreversible state of growth arrest at the cellular level. Though the cells are viable and me

A 16 year old boy named Jake was admitted into the emergency room complaining of headache, fever, stiffness of abdominal muscles and difficulty swallowing. The doctor on staff bega

Extraoral Examination It includes examining the following basic structures which are related to oral cavity. TMJ: Rule out any tenderness, crepitus, clicking or snapping