Class Notes (1,100,000)
CA (630,000)
UTSC (30,000)
BIOB34H3 (300)

BIOB34H3 Lecture Notes - Filum Terminale, Conus Medullaris, Lumbar Vertebrae

Biological Sciences
Course Code
Ted Petit

This preview shows half of the first page. to view the full 3 pages of the document.
Chapters 13/14 The Spinal Cord and Spinal Nerves
Protection and coverings
- Vertebral column
1. the spinal cord is in a canal formed by the vertebral foramina
2. vertebral ligaments also protect
- Fat in the epidural space between wall of vertebral canal and meninges
- Meninges (spinal meninges), cover cord and spinal nerves until they exit vertebral column
External Anatomy
- Extends from brain to second lumbar vertebra
- Two thickened areas
1. cervical enlargement
a. nerves to and from upper limbs arise from this area
2. lumbar enlargement
a. nerves to and from lower limbs arise from this area
- Two grooves
1. anterior median fissure
2. posterior median sulcus
- Conus medullaris
1. end of cord tapers to a cone shape
- Filum terminale
1. extension of pia mater attaches cord to coccyx
- Cauda equina
1. some nerves exit the spinal cord and continue down the vertebral column to exit farther down
- Dorsal and ventral roots fuse to form spinal nerves
Internal Anatomy
- Gray matter
1. has two sides, connected by gray commissure
a. central canal is in center, extends the length of the spinal cord (contains CSF)
b. anterior (ventral) horns - contain cell bodies of motor neurons supplying skeletal muscle
c. posterior (dorsal) horns- contain cell bodies of interneurons, axon terminals of sensory
d. lateral horns- contain cell bodies for autonomic motor neurons which supply
smooth/cardiac muscle and glands, only in thoracic, lumbar and sacral segments
2. function: receives and integrates incoming and outgoing signals
- White matter
1. anterior (ventral) white columns, posterior (dorsal) white columns, lateral white columns
a. ascending (sensory) tracts- carry signals to brain
b. descending (motor) tracts- carry signals away from brain
2. function: transmitting electrical signals
3. ascending tracts
a. spinothalamic (anterior and lateral)
1) carry info on pain, temperature, deep pressure, crude touch (poorly localized)
b. posterior column tracts (fasciculus gracilis, fasciculus cuneatus)
1) carry info on proprioception (sense of body position, comes from muscles, tendons,
joints), fine touch, pressure
You're Reading a Preview

Unlock to view full version