Nervous System Organization and Spinal Cord Flashcards Preview

Anatomy > Nervous System Organization and Spinal Cord > Flashcards

Flashcards in Nervous System Organization and Spinal Cord Deck (38):
1

What is a dendrite?

Highly branched processes that typically function as the “receiving end” for information coming to the neuronal cell body

2

What is an axon hillock?

point of axon origin from the cell body

3

What is an axon terminal?

where the neuron communicates with other cells

4

What is an axon?

A single process arising from the
neuronal cell body that carries information away from the cell body toward other cells

5

What is a neuronal cell body? (soma)

Neuronal cytoplasm contains organelle
that provide energy and synthesize chemical signaling molecules (neurotransmitters) that are critical in cell-to-cell communication.

6

Define synapse

the specialized site of the axon where the neuron communicates with another cell

7

What do synaptic vesicles do?

filled with chemical neurotransmitters that are released upon stimulation

8

What is a synaptic cleft?

narrow gap between pre- and post- synaptic cells into which neurotransmitters are released

9

What are bipolar neurons?

have two distinct processes – one dendrite and one axon. They are found in special sense organs where they relay information about sight, smell or hearing.

10

What are unipolar neurons?

have a dendrite and axon that are basically continuous. This is the typical shape of sensory neurons of the peripheral nervous system.

11

What are multipolar neurons?

have two or more dendrites and an axon. They are the most common type of neuron. This is the typical shape of a motor neuron controlling skeletal muscles.

12

What are the 5 functions of astrocytes?

• help to create and maintain the blood-brain barrier that isolates the CNS from substances circulating in blood
• Provide structural support
• Regulate ion, nutrient and
dissolved gas concentrations in
fluid surrounding neurons
• Take up and recycle
neurotransmitters
• Form scar tissue after neural
injury

13

What are the 6 functions of microglia?

• Migratory cells that continuously move through neural tissue
• Scavenge and remove cellular debris, wastes and pathogens by phagocytosis
• Help to remodel synapses
• Fight microbes and cancer
• Repair trauma
• Respond to autoimmune
diseases

14

What are the 2 functions of oligodendrocytes?

• Provide a structural framework in the CNS by stabilizing the positions of axons
• Produce myelin, a membranous wrapping around CNS axons that functions like insulation on a wire, increasing the speed of nerve impulse transmission

15

What is the function of a Schwann cell?

Produce myelin, a membranous wrapping around PNS axons that functions like insulation on a wire, increasing the speed of nerve impulse transmission
Participate in repair of damaged nerves in the peripheral nervous system

16

Where does the spinal cord end?

Between the L1 and L2 vertebrae

17

What is the cauda equina?

the spinal nerve roots that extend inferiorly beyond the tapered end of the spinal cord resemble a horse’s tail and are called the cauda equina.

18

How many vertebrae are there?

33

19

How many pairs of spinal nerves are there?

31

20

The C1 spinal nerve exits ________ the C1 vertebra pedicle and is somatic motor only.

ABOVE

21

The C8 spinal nerve exits _________ the C7 vertebra pedicle

BELOW

22

At all levels below, spinal nerves exit _______ the corresponding vertebral pedicle.

Below

23

What does the cervical enlargement innervate?

shoulder and upper extremity

24

What does the lumbar enlargement innervate?

pelvis and lower extremity

25

What is the conus medullaris

tapered end of spinal cord

26

What is cauda equina

Nerve roots extending beyond the tapered end of the spinal cord; bundle of nerve roots looks like a “horse’s tail”

27

What is filum terminale

Slender fibrous strand that extends to the coccyx providing longitudinal support to the spinal cord

28

What are the spinal meninges?

3 layers of membranes that surround the spinal cord and provide physical stability and shock absorption. They are continuous with the cranial meninges that surround the brain.

29

What are the functions of cerebrospinal fluid?

this fluid functions as a shock absorber and a diffusion medium for dissolved gases, nutrients, chemical messengers and wastes

30

In a lumbar puncture where is the needle inserted?

Between the 3rd and 4th lumbar vertebrae

31

What is gray matter

Contains the cell bodies of neurons and neuroglial cells

32

What is white matter

contains myelinated axons that are running in bundles carrying either information that is ascending toward the brain or descending from the brain.

33

What do dorsal roots do

carry sensory information into the CNS.

34

What do ventral roots do

carry motor information out of the CNS.

35

What do spinal nerves do

carry both sensory and motor information.

36

What is the directions of sensory information

IN over dorsal root; coming from sensory receptors

37

What is the directions of motor information

OUT over ventral root; going to skeletal muscles

38

Where are sensory neuron cell bodies located?

Dorsal root ganglion