unit 6 Flashcards
List the parts of a muscle.
Muscle fiber
Endomysium
Fascicle
Perimysium
Epimysium
Fascia
difference between isometric
contractions and isotonic contractions
isometric tendon change lengeth isotonic stays the same
difference between the muscle
origin and insertion
Origin – the end that attaches to the more
stationary bone
Insertion – the end that attaches to the more
moveable bone
prime mover
– the main muscle that triggers a
movement
Synergist
– the muscle that assists the prime
mover
Antagonists
oppose the action of the prime
mover to help with control of the movement
Roles of the nervous system
Sensing
◦ Integrating
◦ Responding
CNS
CNS consists of the brain and spinal cord and the name of the nervous system
division
PNS
consists of the network of nerves throughout
the body is the name of the nervous system
division that includes the nerves that extend to
the outlying parts of the body
Sensory
(afferent) division carries signals
from the nerve endings to the CNS
Motor
division transmits information
from the CNS to the rest of the body
Oligodendrocytes
form the myelin sheath
in the brain and spinal cord
Oligodendrocytes
– form the myelin sheath
in the brain and spinal cord
Ependymal cells –
line the spinal cord and
cavities of the brain
Microglia
perform phagocytosis of microorganisms and cellular debris
Astrocytes
– nourish neurons in the brain
tissue
Schwann cells
– form the myelin sheath
around nerves in the PNS
Satellite cells
– nourish the neurons (same
as astrocytes in CNS)
Interneurons
connect incoming sensory pathways with outgoing
motor pathways
Multipolar
One axon multiple dendrites
Brain and spinal cord
Bipolar have
Axon and dendrite
Retina eye
Olfactory nerve (
Unipolar have
Axon branch only
Soma are
The cell body
◦ Control centre that contains the nucleus
Dendrites
Receive signals from the other neurons and send
the information towards the soma
Axon
Carry signals away from the soma
Myelin sheath
Insulates the axon
Nodes of Ranvier
Gaps in the myelin sheath that assist with
conduction of impulses
Synaptic knob are
Neurotransmitter-containing vesicles at the end of
the axon branches
Nerve Impulses
Wave of electrical disturbance that travels
along the surface of a neuron membrane
. Resting potential
Outside the cell = Na+; inside = K+ and negative
ions
Depolarization
Stimulus causes Na+ to enter cell
Repolarization
K+ flows out of the cell; electrical balance is
restored
◦ Na+ and K+ are now on the wrong side
Refractory period
◦
Sodium-potassium pump works to return Na+ and
K+ to the correct side
Electrical synapse
the neurons touch which
allows an action potential to pass directly from
one neuron to the next
Chemical synapse
the neurons do not touch
so neurotransmitters are used to cross the
synaptic cleft and carry the message
Cauda equina
Bundle of nerve roots that protrude from the end of
the spinal cord
Cauda equina
Bundle of nerve roots that protrude from the end of
the spinal cord
Ascending tract
conveys sensory signals up the spinal cord
Descending tracts
conveys impulses down the spinal cord to the
skeletal muscles
Gray matter vs white matter
Gray matter contains no myelin White matter contains myelin
Meningeal layers
Pia mater – innermost layer that contains blood
vessels
Arachnoid mater
what is middle layer (very thin)
what is Dura mater
the tough, outer layer
Subarachnoid space
Between the pia mater and the arachnoid mater
◦ Contains cerebrospinal fluid
The Spinal Cord
has
8 cervical
12 thoracic
5 lumbar
5 sacral
1 coccygeal
Total: 31
