LAB 7: Nervous Tissue, Spinal Cord and Somatic Reflexes Flashcards
Where is the cell body of a sensory neuron that is bringing pain and temp info from the skin?
Dorsal root ganglion
How does a sensory neurons axon enter the spinal cord?
Dorsal rootlets
Where is the target for the axon of a somatic motor neuron?
Tissues of the skeletal muscles
Where is the cell body of a motor neurons?
Ventral horn of spinal cord
How does a motor neurons axon leave the spinal cord?
Ventral root
Where are cell bodies of motor neurons that are part of the sympathetic nervous system?
Lateral grey horn
What does grey matter contain?
Somas, dendrites, and proximal parts of the neural axons.
Site of synaptic contact (synaptic integration)
What does white matter contain?
Myelin (lots), bundles of axons called tracts
What does central canal contain?
Ependymal cells, CSF
What do dorsal root ganglion contain?
Cell bodies of the sensory neurons
receives sensory nerve fibers- sometimes synapse with an interneuron
What do dorsal grey horns contain?
Sensory information.
Grey matter that extends toward dorsolateral surfaces of cord = sensory/ependymal cells – CSF
What do ventral grey horns contain?
Motor information
ependymal cells – CSF
What is the origin and destination of the cuneate fasciculus tract?
O= T6 (from upper limbs and chest), D= gracile fasciculus
What kind of information does the cuneate fasciculus tract carry?
Touch and proprioception
What is the origin and destination of the gracile fasciculus tract?
O= midthoracic and lower parts of body, D= cuneate fasciculus
What kind of information does the gracile fasciculus tract carry?
Touch and proprioception
What is the origin and destination of the spinothalamic tract?
O= spinal cord, D= thalamus
What kind of information does the spinothalamic tract carry?
Pain and temp
What is the origin and destination of the spinocerebellar tract?
O= limbs and trunk, D= cerebellum at near of brain
What kind of information does the spinocerebellar tract carry?
Proprioception
What is the origin and destination of the corticospinal tract?
O= cerebral cortex, D= limbs
What kind of information does the corticospinal tract carry?
Fine motor control
What is the origin and destination of the tectospinal tract?
O= tectum (in midbrain), D= contralateral side of midbrain
What kind of information does the tectospinal tract carry?
Reflexive movement of head and neck to sound and sight
What is the origin and destination of the reticulospinal tracts?
O= reticular formation of brainstem, D= muscles in upper limbs, especially posture and balance
What kind of information does the reticulospinal tracts carry?
Balance and posture, analgersia
What is the origin and destination of the vestibulospinal tract?
O= brainstem vestibular nuclei, D= neurons that control extensor muscles of limbs
What kind of information does the vestibulospinal tract carry?
Keeps balance and head position
What do autonomic reflexes do?
Activate skeletal muscles, cardiac muscles, and glands of the body.
What do somatic reflexes do?
Stimulates skeletal muscles and may act though the spinal cord or cranial nerves
What is the function of a primary afferent?
Informs brain about small changes in muscle length and sudden body movements
What is the function of a secondary afferent?
Signals ongoing info about the changes in muscle length (slower)
What is the function of a gamma motor neuron?
Maintains tension and sensitivity of the intrafusal fibers (muscle spindles)
What is the function of an alpha motor neuron?
Innervates working part of muscle/ contracts muscle (skeletal Muscles)
What are stretch reflexes important postural reflexes because why?
They act to maintain posture, balance, locomotion and equilibrium
When testing the patellar reflex, what muscle is hammed, what muscle contracts, and what type of movement is at what joint?
H- Quardireps femoris muscle, C- Quadriceps femoris, type of M- Extension of the knee
When testing the biceps reflex, what muscle is hammed, what muscle contracts, and what type of movement is at what joint?
H- Biceps brachii, C- Biceps brachii, Type of M- flexion of the elbow
When testing the triceps reflex, what muscle is hammed, what muscle contracts, and what type of movement is at what joint?
H- Triceps brachii, C- triceps brachii, Type of M- Extension of elbow
When testing the Achilles reflex, what muscle is hammed, what muscle contracts, and what type of movement is at what joint?
H- Gastronemius soleus, C- Gastronemius, Type of M- Plantar flexion of the ankle
