Chapter 3: Anatomy of the Nervous System

nerves in the sympathetic nervous system project the synapse on….

second stage neurons at distance from their organs 

Parasympatheic system act on 3 principles

1. stimulate organize and mobilize energy in threating situations

2. automatic targets receive opposing sympathetic and parasympathetic impulses 

3. sympathetic changes are indicative of psychological arousal whereas parasympathetic indicates relaxation 

cranial nerves

12 pairs of crucial nerves which project from the brain 

sensory nerves: 

1. olfactory 

2. optic  

vagus nerves

longest cranial nerve which contains motor and sensory fields travelling to and from the gut

afferent nerves…

approach arrive advance to the CNS

efferent nerves….

exit, escape, embark to the CNS

sympathic nerves 

autonomic motor nerves that project from the CNS in the lumbar and thoracic regions of the spinal cord 

parasympathetic nerves

autonomic motor nerves that project from the brain and sacral region of the spinal cord

Subarachorid spaces, central canal and cerebral ventricles connected by…

a series of openings thus forming a single reservoir

choroid plexuses

networks of capillaries that protrude into ventricles from the Pia mater which is traditionally thought to be where cerebrospinal fluid is produced

Chanel proteins

channel in which certain molecules can pass

signal proteins

transfers signals to the inside of the neruon when particular molecules bond to them on the outside of the membrane

neruons are classified by their…

number of processes emanating from their cell bodies

oligedendrocytes 

glial cells with extensions that wrap around the axons of some neurons of the CNS 

astrocytes seem to play a role in…

allowing the passing of some chemicals from the blood into CNS neurons and in blocking other chemicals

glial network

thought to be dwelling places of thoughts 

astrocytes have 15 distinct types with….

their own physiology, structure, and specific location in the brain

2 types of neuroanatomical tracing techniques

1. anterograde tracing methods

2. retrograde tracing methods

anterograde tracing method

used to trace the paths of axons projecting away from cell bodies located in a particular area (injected into cell body)

retrograde tracing methods 

used to trace paths of axons projecting into a particular area (injected into buttons)

Each spinal nerves are divided as they near the cord and axons are joined via:

1. the dorsal root

2. the ventral root

dorsal root

1. sensory info

2. afferent

ventral root

1. motor info

2. efferent