Intro to Nervous System and Spinal Cord

Question 1

Central Nervous System

Answer 1

Brain

Spinal Cord

Question 2

Peripheral Nervous System

Answer 2

Autonomic Ganglia
Sensory Ganglia
Nerves and plexuses

Question 3

Nervous tissues is defined as:

Answer 3

those cells and portions of the body characterized by voltage dependent changes in the permeability to the sodium ions

Question 4

Hallmark of nervous system:

Answer 4

its excitability and the conduction of signals

Question 5

The Neuron Theory

Answer 5

Functions of the nervous system reflect the functions of individual neurons, groups of neurons, and their connections

Question 6

Gray matter

Answer 6

where there is a concentration of neuronal cell bodies with dendrites

Question 7

White matter

Answer 7

concentration of axons from one place to another in the CNS

Question 8

Somatic efferents

Answer 8

move skeletal muscle

Question 9

Visceral efferents

Answer 9

move smooth muscle (autonomic)

Question 10

Somatic afferents

Answer 10

give precise localized information

Question 11

Visceral afferents

Answer 11

lots of information but poorly localized

Question 12

Glia Cells of the CNS

Answer 12

Fibrous (white matter) and protoplasmic (grey matter) astrocytes
Oligodendrocytes (myelin forming)
Microglia (scavengers; monocyte derived)
Ependyma (line ventricles and central canal - contribute to choroid plexus)

Question 13

Compared to unmyelintated cells, myelinated cells:

Answer 13

have huge fibers

transmit signals faster

Question 14

What kind of cells make myelin

Answer 14

Oligodendrocytes in CNS

Sheath cells in PNS

Question 15

Peripheral nerves can be described in terms of functional components of the fibers they carry:

Answer 15

Sensory fibers bring information to the CNS (Afferent)

Motor fibers carry information toward muscles in the PNS (Efferent)

Question 16

Sensory Fiber Neurons

Answer 16

Pseudounipolar
Spinal Dorsal Root Ganglia
Cranial Nerve Ganglia

Question 17

Motor Fiber Neurons

Answer 17

Multipolar Neurons
Spinal cord - spinal nerves
Brainstem - cranial nerves

Question 18

Organization of the PNS: Somatic Afferents

Sensory fibers bring information to the CNS (Afferent)

Answer 18

Come from the body (soma) and carry precise information about place
Pain 
Temperature
Light Touch
Vibration

Question 19

Organization of the PNS: Visceral Afferents

Sensory Fibers bring information to the CNS (Afferent)

Answer 19

Come from internal organs (viscus) of the body and carry a lot of information that we cannot perceive
Osmolarity of the portal blood
CO2 in the blood and pressure in the carotid
Na+ in Blood
Pain (contractions/cramping, anoxia, distension)

Question 20

Organization of the PNS: Somatic Efferents

Motor Fibers carry information toward muscles in the PNS (Efferent)

Answer 20

Multipolar neurons of the brainstem and ventral horn of the spinal cord
Connect directly from CNS neurons to cells of striated/skeletal muscles
Produce movement
Under direct voluntary control
May have automatic control but are able to be consciously activated or suppressed
Loss of cells in the CNS or their axons in peripheral nerves results in loss of movement
Weakness in a muscle is an innervation problem