Spinal Cord Anatomy Quiz
Questions: 16 · 10 minutes
1. A small central spinal cord cavity first disrupts fibers crossing near the central canal, producing bilateral segmental loss of pain and temperature sensation. Which structure is most likely affected?
Anterior white commissure
Posterior median septum
Dorsal root ganglion
Fasciculus gracilis
2. What is the correct order of the spinal meninges from outermost to innermost?
Dura mater, arachnoid mater, pia mater
Arachnoid mater, dura mater, pia mater
Dura mater, pia mater, arachnoid mater
Pia mater, arachnoid mater, dura mater
3. Immediately after a dorsal root and a ventral root unite, the resulting spinal nerve contains what type of fibers?
Sensory fibers only
Preganglionic autonomic fibers only
Somatic motor fibers only
Both sensory and motor fibers
4. Which structure extends inferiorly from the conus medullaris and helps anchor the spinal cord and dural sac?
Dorsal root ganglion
Anterior median fissure
Filum terminale
Fasciculus cuneatus
5. Which statement correctly distinguishes the dorsal and ventral roots of a spinal nerve?
Both roots carry only sensory fibers, but from different body regions
The dorsal root carries motor fibers, while the ventral root carries sensory fibers
The dorsal root carries sensory fibers, while the ventral root carries motor fibers
Both roots carry mixed sensory and motor fibers before they unite
6. In a typical upper thoracic spinal cord segment, the lateral horn primarily contains which neurons?
Preganglionic sympathetic neurons
Lower motor neurons supplying the diaphragm
Postganglionic parasympathetic neurons supplying abdominal organs
Somatic sensory neurons receiving input from skeletal muscle
7. A tract is identified in the medial part of the posterior funiculus and carries vibration, fine touch, and conscious proprioception from the lower body. Which tract is it?
Lateral spinothalamic tract
Fasciculus cuneatus
Fasciculus gracilis
Anterior corticospinal tract
8. A lesion selectively interrupts one dorsal root before it joins the spinal cord. Which effect is most directly expected?
Loss of all motor output below the lesion on both sides
Reduced sensory input from the corresponding dermatome, with ventral-root motor output preserved
Loss of pain and temperature sensation from the entire opposite side of the body
Interruption of sensory and motor fibers in every spinal nerve below the lesion
9. Which spinal cord structure consists of tooth-like lateral extensions of pia mater that help stabilize the cord within the dural sac?
Posterior longitudinal ligament
Denticulate ligaments
Filum terminale
Arachnoid trabeculae
10. An MRI shows a bundle of lumbar and sacral nerve roots descending through the vertebral canal below the conus medullaris. What is this bundle called?
Cervical enlargement
Filum terminale
Posterior funiculus
Cauda equina
11. During placement of an epidural anesthetic, medication is delivered outside the dura mater. What normally occupies this spinal epidural space?
Only cerebrospinal fluid and spinal nerve roots
Fat and an internal vertebral venous plexus
Gray commissural tissue and the central canal
Arachnoid trabeculae and denticulate ligaments
12. A lumbar puncture is commonly performed at L3-L4 or L4-L5, below the usual end of the adult spinal cord. From which space is cerebrospinal fluid collected?
The central canal within the conus medullaris
The spinal epidural space
The potential space between pia mater and spinal cord tissue
The subarachnoid space of the lumbar cistern
13. Damage to the right lateral corticospinal tract within the spinal cord would most directly impair which function?
Pain and temperature sensation on the right at the affected segment only
Fine touch from the left side below the lesion
Voluntary movement on the right below the lesion
Autonomic output from both sides of every spinal segment
14. Which description of the spinal cord's central canal is accurate?
It is a venous channel located between the dura mater and vertebrae
It is a small, ependyma-lined channel containing cerebrospinal fluid
It is a white-matter passage carrying descending motor axons
It is the space surrounding each dorsal root ganglion
15. In most adults, at approximately which vertebral level does the spinal cord end as the conus medullaris?
At T6
Between L4 and L5
At S1
Between L1 and L2
16. Why are the cervical and lumbosacral enlargements wider than nearby portions of the spinal cord?
They contain additional neurons serving the upper and lower limbs
They contain the attachment points of the denticulate ligaments
They are the main sites where cerebrospinal fluid is produced
They mark the transition from gray matter to white matter