W6 Anatomy of the Spinal Cord Flashcards
what different things does the spinal cord process information from?
processes afferent information from muscles, tendons, joints, ligaments, blood vessels, skin and viscera and discharges efferent commands that control muscles and regulate glands
what is the medulla spinalis also known as?
the spinal cord
where does the spinal cord leave the skull from and what does it run through?
leaves from foramen magnum and runs through the vertebral column (from the medulla oblongata to 6th/7th lumbar vertebrae)
what does the centre of the spinal cord contain?
a central canal filled with cerebrospinal fluid and lined with ependymal cells
what do the spinal nerves inervate?
neck, trunk, tail, limbs and caudal and dorsal surfaces of the head
what segments is the spinal cord divided into?
cervical, thoracic, lumbar, sacral and coccygeal
what is the reason for dividing the spinal cord?
divided due to the attachments of dorsal and ventral roots to the cord, each root is made up of thousands of axons
what is the difference between dorsal and ventral roots of the spinal nerves?
dorsal - convey sensory (afferent) input to the spinal cord
ventral - carry motor (efferent) output to the muscles and glands
each spinal cord segment gives rise to what?
gives rise to paired spinal nerves
dorsal and ventral spinal roots arise as a number of rootlets, what else is present on a dorsal root?
a spinal ganglion (cell bodies outside of the spinal cord and brain are called ganglion)
the first how many segments have rootlets that emerge to form spinal roots of the accessory nerve?
the first seven
at what two locations is the spinal cord increased in diameter (seems like a bumps), why is this?
the cervical enlargement that gives rise to nerves that form the brachial plexus that innervates the thoracic limb
the lumbar enlargement which innervates the pelvic cavity and pelvic limbs (segments L5, L6, L7 and part of S1)
what is a nerve plexus?
a complex interwoven network of nerves
what is the brachial plexus formed by?
the ventral branches of C6, C7, C8, T1 and T2
the large somatic nerve plexus gives origin to nerves that supply what?
the thoracic limb
what root/branches innervates epaxial tissues?
dorsal branches
what root/branches innervate hypaxial tissues, including the limbs?
ventral branches
after birth, is there more growth to the spinal cord or the vertebral column?
the vertebral column
all remaining spinal nerves leave the canal through what?
the sacral foramina