BIOL 1303 Lecture Outline
Nervous System III- Spinal Cord and Spinal Nerves
Chapter 13
I. Functions
A. Spinal nerves: carry sensory information to and motor information from the CNS
B. Spinal cord: help maintain homeostasis with quick reflexive responses to stimuli and carry
sensory and motor information to and from the brain
II. Protection of Spinal Cord
A. Veterbral column
1. bone of vertebrae provide physical protection
2. spinal cord lies within the vertebral canal (vertebral foramina)
B. Meninges: three layered connective tissue covering of the brain and spinal cord
1. epidural space
a. between the vertebrae and dura mater
b. cushion of fat and CT
2. dura mater
a. most superficial
b. dense irregular CT
3. subdural space
a. between dura mater and arachnoid mater
b. filled with interstitial fluid
4. arachnoid mater
a. collagen and elastic fibers
5. subarachnoid space
a. between arachnoid mater and pia mater
-1-
, b. filled with cerebrospinal fluid
6. pia mater
a. thin connective tissue
b. highly vascular
c. adheres to surface of brain and spinal cord
d. denticulate ligaments
1. thick extensions of pia mater that fuse with arachnoid and dura mater
2. protect against shock and sudden displacement (hold SC to dura mater)
7. HINT: PAD= Pia, Arachnoid, Dura
C. Cerebrospinal fluid (CSF)
1. provides cushioning of CNS
2. in subarachnoid space, ventricles of brain, and central canal of SC
3. ependymal cells produce and circulate CSF
III. Structure of Spinal Cord
A. Location
1. inferior to brain
2. connect to medulla oblongata
3. within the vertebral canal
B. Longitudinal Section
1. cervical enlargement (C4-T1): nerves of upper limbs arise here
2. lumbar enlargement (T9-T12): nerves of lower limbs arise here
3. conus medullaris: between L1 and L2, termination of SC
4. cauda equine: “horse tail” nerve axons that arise from the inferior SC and continue
down vertebral canal before exiting
-2-
Nervous System III- Spinal Cord and Spinal Nerves
Chapter 13
I. Functions
A. Spinal nerves: carry sensory information to and motor information from the CNS
B. Spinal cord: help maintain homeostasis with quick reflexive responses to stimuli and carry
sensory and motor information to and from the brain
II. Protection of Spinal Cord
A. Veterbral column
1. bone of vertebrae provide physical protection
2. spinal cord lies within the vertebral canal (vertebral foramina)
B. Meninges: three layered connective tissue covering of the brain and spinal cord
1. epidural space
a. between the vertebrae and dura mater
b. cushion of fat and CT
2. dura mater
a. most superficial
b. dense irregular CT
3. subdural space
a. between dura mater and arachnoid mater
b. filled with interstitial fluid
4. arachnoid mater
a. collagen and elastic fibers
5. subarachnoid space
a. between arachnoid mater and pia mater
-1-
, b. filled with cerebrospinal fluid
6. pia mater
a. thin connective tissue
b. highly vascular
c. adheres to surface of brain and spinal cord
d. denticulate ligaments
1. thick extensions of pia mater that fuse with arachnoid and dura mater
2. protect against shock and sudden displacement (hold SC to dura mater)
7. HINT: PAD= Pia, Arachnoid, Dura
C. Cerebrospinal fluid (CSF)
1. provides cushioning of CNS
2. in subarachnoid space, ventricles of brain, and central canal of SC
3. ependymal cells produce and circulate CSF
III. Structure of Spinal Cord
A. Location
1. inferior to brain
2. connect to medulla oblongata
3. within the vertebral canal
B. Longitudinal Section
1. cervical enlargement (C4-T1): nerves of upper limbs arise here
2. lumbar enlargement (T9-T12): nerves of lower limbs arise here
3. conus medullaris: between L1 and L2, termination of SC
4. cauda equine: “horse tail” nerve axons that arise from the inferior SC and continue
down vertebral canal before exiting
-2-
