Intro to Nervous system

Question 1

Define components of CNS and PNS

Answer 1

CNS: brain and spinal cord. Transforamation of sensory-motor information. PNS is split into somatic and visceral nervous system. PNS consist of spinal, cranial, and splanchnic nerves. Motor, sensory, and automatic signals between CNS and body.

Question 2

What types of tissues or organs are innervated by the somatic nervous system?

Answer 2

Somatomotor: voluntary and reflex contraction of skeletal muscle somatosensory: sensory innervation of skin, muscles, and joints

Question 3

What types of tissues or organs are innervated by the visceral nervous system?

Answer 3

visceromotor (ANS)- involuntary contraction of smooth muscle, cardiac muscle, adn glands viscerosensory-modulates blood pressure, and chemistry, respiration.

Question 4

Describe the common morphoogical features of the spinal cord.

Answer 4

gray matter- neuronal cell bodies white matter-conatians myelinated axons.

white matter-myelinated axons-carries info from outside world.

Question 5

Describe unique features of the cervical and lumbar parts of spinal cord.

Answer 5

• Cervical and lumbar parts of the spinal cord have large ventral horns that contain motor neurons that innervate either the upper or lower limbs
• Dorsal white matter in the cervical cord contains axons for transmission of sensory information from all parts of the body
• Dorsal white matter in the lumbar cord contains axons for transmission of sensory information from the lower limbs

Question 6

Describe unique features of the thoracic spinal cord.

Answer 6

Thoracic spinal cord has:

• small ventral horns that contain neurons that innervate trunk muscles
• a special area of gray matter (lateral horn) that houses the cell bodies for sympathetic (preganglionic) neurons.
• dorsal white matter contains axons for transmission of sensory information from the trunk and lower limbs

Question 7

What are the components of the dorsal primary ramus? What tissues/muscles does it innervate?

Answer 7

innervates the deep back muscles and overlying skin.

Posterior cutaneous nerves: has somatosensory and ANS

musculocutaneous: has somatamotor, somatasensory, ANS

Question 8

What are the components of the ventral pimrary ramus and what tissues does it innervate?

Answer 8

Innervates the rest of the muscles of neck, trunk, limbs, and overlying skin.

Question 9

What are the nerve components of the ventral and dorsal root?

Answer 9

ventral root-contain motor fibers only-carries motor info from spinal cord to the periphery

dorsal roots-contain sensory fibers only-carries sensory info into dorasal horn of spinal cord from periphery. composed of sensory axons whose cell bodies are in the dorsal root ganglion.

Question 10

Define dermatone and list three important ones.

Answer 10

A dormatone is the area of skin that is innervated by the sensory cutaneous fibers of a single pair of spinal nerves or spinal cord segment.

• nipple-T4
• Umbilicus-T10
• Pubic bone-L1