Chapter 13: The spinal cords internal structure

Question 1

What are the 2 main areas of the internal structure of the spinal cord?

Answer 1

White matter and grey matter

Question 2

What is the white matter made up of?

Answer 2

Largely consists of myelinated axons for rapid nerve impulse condition

Question 3

What are the 3 pairs of anatomical areas in the white matter?

Answer 3

Dorsal funiculi - separated by median sulcus

lateral funiculi - separated by grey matter

ventral funiculi - separated at ventral median fissure

Question 4

What are spinal cord tracts?

Answer 4

Functionally related groups of neurons

Question 5

What are the two general types of spinal cord tracts?

Answer 5

Ascending/sensory tracts and the descending/motor tracts

Question 6

What are the fasciculus gracilis and cuneatus ascending/sensory tracts?
HINT: WHAT ARE SENSORY NEURONS

Answer 6

They go through the dorsal columns and are mainly for touch.

Question 7

What are the dorsal and ventral spinocerebellar ascending/sensory tracts?
HINT: WHAT ARE SENSORY NEURONS

Answer 7

they go through the lateral funiculi and are used for proprioception

Question 8

What are the lateral and ventral spinothalamic ascending/sensory tracts?
HINT: WHAT ARE SENSORY NEURONS

Answer 8

go through the lateral and ventral funiculi for pain and temperature (PNS)

Question 9

How Many descending/motor tracts are there?

Answer 9

There are 7 pairs that conduct nerve impulses down from the brain through the spinal cord.

Question 10

What are the lateral and ventral corticospinal/Pyramidal tracts responsible for? (descending/motor tracts)

Answer 10

voluntary skeletal muscle movements

Question 11

What are rubrospinal, medial and lateral reticulospinal, vestibulospinal, and tectospinal tracts responsible for? (descending/motor tracts)

Answer 11

involuntary postural skeletal muscle actions

Question 12

What grey matter in the spinal cord?

Answer 12

Includes nonmyelinated parts of neurons and synapses; more complex functions take place here compared to white matter.

Question 13

What is the gray commissure?

Answer 13

Connects the 2 halves of gray matter; neurons cross over here; central cancel goes through

Question 14

What are the lateral horns?

Answer 14

Project laterally from gray commissure; only in thoracic and lumbar regions of the spinal cord; contain parts of neurons of the SANS (sympathetic autonomic system)

Question 15

What are the dorsal horns?

Answer 15

Project dorsally from gray commissure; involved in sensory functions

Question 16

What are the ventral horns?

Answer 16

project ventrally from gray commissure; involved in motor functions