Ch 15 Flashcards
(30 cards)
peripheral vs central nervous system
peripheral - all except brain/spinal cord
central - brain/spinal cord
a neural circuit contains both what
central and peripheral nervous system interactions
the CNS exhibits ___ & ____ and is composed of …..
exhibits centralization and cephalization
composed of grey + white matter
define centralization & cephalization
central- neurons concentrated in central areas NOT randomly dispersed
ceph- concentrated at one end of the body (head)
in the CNS of vertebrates there are both ___ cells and ____
glial cells and neurons
what are neuroglia
= space fillers, protect & nourish neurons
* CANNOT generate action potentials
- # vary between species
4 types of neuroglia
- astrocytes
• many
• maintain blood brain barrier
• guide young neurons
• big role in supporting neurons - oligodendrocyte
• form and maintain myelin sheath in CNS - microglia
• phagocytes = remove debris, damaged cells - ependymal cells
• assist in circulation of cerebrospinal fluid
in vertebrates how is neural tissue protected (4)
- closed in by bone
- meninges
- fluid
- blood brain barrier
mammals have how many meninges ? do all vertebrate have this many? what is in between the meninges layers?
mammals = 3
- dura mater
- arachnoid mater
- pia mater
between layers is cerebrospinal fluid
blood brain barrier is formed by ____
tight junctions
- allows good in and excludes harmful substances
compare white vs grey matter
white - bundles of axons covered in myelin sheath
grey - neuronal cell bodies, dendrites, glial cells
separation of white and grey matter is ____ in all vertebrates, while organization is ____ across vertebrate classes
separation - found in ALL
organization - different across vertebrates
describe spinal cord and 2 pathways
- local circuit (afferent,interneuron,efferent)
ascending and descending pathways
vertebrate brain has __ major regions and ___ subdivisions, name
3 major regions and 5 subdivisions
- forebrain
• tel (motor control, emotions, memory)
• dien (sensory relay, circadian clock) - midbrain
• mesen (visual & auditory) - hindbrain
• meten (motor coordination, lessen motor control)
• myelen (respiratory control)
the human brain has ____ of function
localization of function
?? motor vs sensory homunculus
motor
- sends commands to muscles
- grey matter
sensory
- receives info from muscles
larger brains with more ___ allow for more ___ integration (mammals)
more neurons = more complex integration (forebrain)
forebrain is larger in ___ & ____
mammals and birds
describe PNS
- autonomic
- sympathetic / para
- somatic
- skeletal muscles
what are some organs innervated by both para and symp ? not dually innervated?
innervated
- lungs, heart, stomach, gut
NOT
- liver, gull bladder, sweat glands
what is unique to sympathetic ?
adrenal medulla
parasympathetic are for ___ & ____ dominance ? what about sympathetic and they are both ____ muscles
para - rest & digest
sympathetic - flight or fight
involuntary muscles
describe enteric nervous system
surround the GI tract
- entirely peripheral and receives input from both sympathetic & parasympathetic divisions
* controls gut motility
for sym and para:
origin of pre ganglionic neuron
sym - thoracolumber origin
para - craniosacral origin
