Week 7 - Spinal Cord Flashcards
In an adult, the spinal cord originates at the level of ___________, and ends at the level of ____________.
foramen magnum
inter-vertebral disk L1-L2
Arbitrarily, the spinal cord is divided into _________ segments, namely: ___ cervical; ___ thoracic; ___ lumbar; ___ sacral; and ___ coccygeal. The segments are represented by emerging from the spinal cord roots of the _______ nerves.
31 8 12 5 5 1 spinal
The anterior (ventral) roots of each spinal nerve represent a bundle of axons from ___________ and __________ motor neurons of the spinal cord. These neurons (soma) are correspondingly situated within the _______ gray horns and _______ gray horns of the spinal cord.
somatic
visceral
ventral
lateral
The posterior (dorsal) roots of each spinal nerve represent a bundle of axons from__________ and _________ sensory neurons, somas of which are situated within __________ .
somatic
visceral
dorsal root ganglia
The spinal cord is of the following approximate length __________ and width __________. It is flattened in __________________ direction.
45cm
2cm
anterio-posterior
There are two spinal cord enlargements: the ________________ enlargement, which represents the _____________ segments of the spinal cord, supplying upper trunk and upper extremities, and the lumbar enlargement, which represents the segments ________________ of the spinal cord, supplying the lower trunk and the lower extremities.
cervical
C4-T1
T9-T12
The spinal cord is divided onto two halves by the __________ fissure and the __________ sulcus.
anterior median
posterior median
The end of the spinal cord is called ____________ as it is narrows down, and resembles a cone or a sharpened pencil. This structure is anchored to the coccyx by the extension of the pia matter, resembling thin thread. It is called: _____________.
conus medullaris
filum terminale
Horizontally, the spinal cord is anchored to the spinal column by projections of the pia matter, which are called: ________________.
denticulate ligaments
The spinal cord is covered by the following meninges from the outside to inside direction: ____________.
dura mater, arachnoid mater, pia mater
Overall, the spinal cord is protected from the physical injury by the following layers: ________________.
vertebra, epidural space (adipose tissue), dura mater, arachnoid mater, subarachnoid space (CSF), pia mater
The outside matter of the spinal cord is _______________ and represents spinal cord ________________. There are the following white matter columns: __________________________.
white matter
funiculli
anterior white columns, posterior white columns, lateral white columns
List spinal cord tracts to master and whether they are motor or sensory tracts: _______________________________.
pyramidal/corticospinal tracts - motor
dorsal column tracts, spinocerebellar tracts, spinal thalamic tracts - sensory
The gray matter of the spinal cord is in a shape of a _________, and is comprised of ___________. There are ________ horns, ____________ horns, and in some segments (____________) ___________ horns.
H or butterfly horns anterior posterior thoracic, lumbar, sacral (T1-L3, S2-S4) lateral
Posterior or dorsal horns hold ______ neurons. Anterior or ventral horns hold __________ neurons. Lateral horns hold _________ neurons.
somatic & visceral sensory
soma of somatic motor
soma of visceral motor
The cross-bar of the gray matter and surrounding white matter represent the connections between right and left halves of the spinal cord. They are called respectively as the following: __________ and ___________.
median gray commissure
median white commissure
Cortico-spinal (pyramidal) R/L tracts (situated within ____________ and ___________ columns of the spinal cord), are efferent tracts, connecting upper motor neurons of the opposite hemisphere with the lower motor neurons of the _______________. This paired tract provides conscious control of _________________.
lateral
anterior
ventral gray horns of the spinal cord
skeletal muscle contraction
Posterior (dorsal) column R/L tracts are afferent tracts, conducting the following sensations from the body below the head to the opposite hemisphere (somato-sensory areas) via the thalami for the conscious use: ______________.
conscious proprioception, vibration, fine touch, stereognosis
Spino-cerebellar (R/L postero- and antero-lateral) tracts are afferent tracts, carrying the following sensations from the body below the head to the corresponding cerebellar hemispheres for sub-conscious use: __________.
subconcious proprioception, vibration
Spino-thalamic tracts (R/L lateral and anterior) are afferent tracts providing the following sensations from the body below the head to the contra-lateral thalamus, and, subsequently, to the somato-sensory areas of the opposite site hemispheres: _____________________.
pain, temperature, light or crude touch
Spinal nerves are very short. They are only ________cm in length. They are located within _______.
1
intervertebral foramena
First seven cervical spinal nerves emerge from the spinal cord at the level: ____________.
above corresponding vertebrae
The eighth cervical spinal nerve emerges from the spinal cord at the level of: _________________.
between C7 & T1
All subsequent spinal nerves below C8 emerge from the spinal cord at the level of: ___________.
below corresponding vertebra
