Ch.7 Flashcards
what do axons travel through to get to the spinal cord
corticospinal tracts
how many separate tracts does the corticospinal tract have?
2
what info does the lateral corticospinal tract send
sends info to arms and legs
what info does the anterior/ventral corticospinal tract send
sends info to trunk, control the muscles of the core or midline of the body
what are upper motor neurons
bundles of axons that extend from the cell bodies in the motor cortex found along the corticospinal tract
where are lower motor neurons found
gray matter of the spinal cord
how many nerves are in the spinal cord?
31
what does the spinal cord do?
sends signals to and from the body
what info is processed by the dorsal root?
afferent sensory info
what info is processed by the ventral root?
efferent motor info
what do interneurons do?
connect the dorsal root (sensation) to the lower motor neurons
what is the reflex arc
occurs when someone touches something hot
how does the reflex arc get processed by nuerons
sensory neuron -> interneuron -> lower motor neuron
what are the 3 types of muscles
cardiac, smooth, and skeletal
where is cardiac muscle located
heart
where is smooth muscle located
organs
biofeedback
looks at how we may be able to control more movement than we typically do such as holding breath
what two types of fibers make of the skeletal muscle
extrafusal and intrafusal
what are extrafusal fibers
muscle cells that contract to shorten a muscle
what are intrafusal fibers
-muscle cells that detect changes in muscle length
-sensory receptors monitor stretching
what is the neuromuscular junction
the synapse formed when the axon terminal of a motor neuron positions itself in a section of the extrafusal muscle fiber known as the motor end plate
what is the motor end plate
an area that is highly excitable and appropriate for the initiation of action potentials
what are antagonistic muscles
produce actions that are opposite of one another for example biceps and triceps enable the arm to move toward and away from the body
proprioception
ability to sense the position, orientation, and movement of ones own body