Spinal Cord Structure and Function Quiz

Each segment of the spinal cord gives rise to a pair of spinal nerves.

Humans have 31 pairs of spinal nerves, one pair for each side of the midline.

Spinal nerves combine sensory and motor fibers, enabling communication between the central nervous system (CNS) and the body.

The dorsal root contains the cell bodies of sensory neurons, which have two axons.

The peripherally projecting axon collects sensory information from the body and carries it to the spinal cord.

The centrally projecting axon carries sensory information from the dorsal root ganglion to the spinal cord.

The ventral root carries the axons of motor neurons, which are found in the ventral part of the spinal cord.

The ventral root carries motor commands from the spinal cord to skeletal muscles.

The space between the pia mater and arachnoid mater, containing cerebrospinal fluid (CSF) and small blood vessels.

A space located between the dura mater and the vertebral canal, containing small veins and fat.

Carry sensory information from the body towards the spinal cord.

Carry motor commands from the spinal cord to muscles.

A chain of ganglia located on either side of the vertebral column, containing cell bodies of sympathetic neurons.

The area in the grey matter of the spinal cord responsible for processing sensory information.

The area in the grey matter of the spinal cord that houses motor neurons, which control muscle movement.

The thickening of the spinal cord in the lumbar region, giving rise to the lumbar and sacral spinal nerves.

The tapering end of the spinal cord, typically ending around the L1/L2 vertebral level.

A bundle of spinal nerve roots (from L2 to S5 and the coccygeal nerve) that extends down from the conus medullaris through the lumbar cistern.

An enlarged subarachnoid space filled with cerebrospinal fluid (CSF), located between vertebral levels L1/L2 and S2/S3.

A thin structure that extends from the pia mater and anchors the spinal cord to the coccyx.

A procedure to insert a needle into the subarachnoid space within the lumbar cistern (between L3/L4 or L4/L5 vertebrae) to collect CSF.

The butterfly-shaped region of the spinal cord that contains the cell bodies of neurons. It's more prominent in the lumbar and sacral levels.

The outer region of the spinal cord that contains ascending and descending axons. It's more prominent in the cervical levels due to the many tracts.

Carries information about pain, temperature, itch, and light touch from the body to the brain.

Transmits information about fine touch and body awareness (conscious proprioception) from the body to the brain.

Carries information about body position and movement without conscious awareness, essential for coordination and balance.

Controls voluntary, conscious movements and involves the lateral and anterior corticospinal tracts.

Involved in non-conscious muscle control for balance, posture, and reflexes. Examples include reticulospinal and vestibulospinal tracts.

Neurons in the dorsal root ganglion (DRG) carry pain and temperature signals into the spinal cord.

Sensory neurons synapse with interneurons in laminae I or V of the spinal cord, leading to a crossover to the opposite side.

The axons ascend through the brainstem and synapse in the ventral posterior thalamic nuclei, which are organized by body region.

A pathway in the spinal cord that carries sensory information about touch, pressure, and vibration from the body to the brain. It travels ipsilaterally (on the same side) through the dorsal column of the spinal cord.

A specialized tract within the dorsal column of the spinal cord that carries sensory information from the lower body, including the legs, feet, and trunk.

A specialized tract within the dorsal column of the spinal cord that carries sensory information from the upper body, including the arms, hands, and torso.

The primary motor pathway that controls voluntary movement of skeletal muscles. It originates from the primary motor cortex and descends to the spinal cord.

The part of the pyramidal motor pathway where 90% of the fibers cross over (decussate) at the medulla-spinal cord junction, allowing the left brain to control the right side of the body and vice versa.

The part of the pyramidal motor pathway where 10% of the fibers do not cross over (decussate), allowing the brain to control trunk muscles directly.

A region in the grey matter of the spinal cord involved in processing pain signals from nociceptive sensory neurons.