Nervous Tissue - E4

Question 1

Composition of the central nervous system

Answer 1

brain and spinal cord

Question 2

Composition of the peripheral nervous system

Answer 2

Somatic NS - voluntary
Autonomic NS - involuntary
Enteric NS - involuntary

Question 3

“Entero”

Answer 3

small intestine

Question 4

sympathetic

parasympathetic

Answer 4

excite
relax
both motor portion of autonomic NS

Question 5

Another name for autonomic NS

Answer 5

visceral NS

Question 6

2 major cell types of the nervous tissue

Answer 6

neurons - conduct action potentials

neuroglia - support/aid neurons

Question 7

what is an action potential?

Answer 7

movement/gradient of chemicals

Question 8

properties of neurons

Answer 8

1. excitability - respond to stimuli
2. conductivity - create electrical signals
3. secretion - release chemical messengers

Question 9

Chromatophilic substance

Answer 9

also called Nissl bodies

dense networks of rough ER in the soma of neurons

Question 10

Dendrites vs Axons

Answer 10

dendrites receive the signals, highly branches

axons send the signals, long w/few branches

Question 11

axoplasm

axolemma

Answer 11

cytoplasm of axon

plasma membrane of axon

Question 12

Terminal arborization

Answer 12

synapses w/another neuron, muscle, gland, or cell

contain terminal boutons that contain the chemical messengers

Question 13

Structural classification of neurons

Answer 13

1. multipolar - many dendrites, 1 axon
2. bipolar - 1 dendrite, 1 axon
3. unipolar - 1 process which branches

Question 14

Functional classification of neurons

Answer 14

based on direction the impulse travels

1. sensory (afferent) - receptor to CNS
2. motor (efferent) - CNS to effector
3. association (interneurons) - connect sensory and motor

SAME

Question 15

Neuroglia in general

Answer 15

supportive cells
cover non-synaptic parts of neurons
can divide and multiply
outnumber neurons

Question 16

CNS neuroglia

Answer 16

1. astrocytes: largest & most common, form supportive network, contribute to blood-brain barrier
2. oligodendrocytes: form myelin sheath in CNS
3. microglia: derived from WBCs, phagocytes
4. ependymal cells: produce cerebrospinal fluid, epithelial cells, line ventricles and central canal

Question 17

PNS neuroglia

Answer 17

1. Schwann cells: form myelin sheath in PNS

2. Satellite cells: support cells in ganglia, surround somas

Question 18

Myelin Sheath

Answer 18

Lipoprotein

Electrically insulates axon

Question 19

Node of Ranvier

Answer 19

myelin sheath gap = bare axolemma

Question 20

Nerve fiber

Answer 20

axon (usually) or dendrite

Question 21

nerve

Answer 21

bundle of fibers in PNS w/C.T. coats

1. epineurium - surrounds entire nerve
2. perineurium - surrounds fascicle
3. endoneurium - surrounds single fibers

Question 22

tract

Answer 22

bundle of fibers in CNS (no C.T.)

Question 23

Ganglion

Answer 23

“knot”

collection of neuron somas in PNS

Question 24

Nucleus

Answer 24

collection of neuron somas in CNS

Question 25

White matter vs. Gray matter

Answer 25

white - myelinated axons (conduction)

gray - somas, unmyelinated axons, neuroglia (decision-making)