Organ Systems Brons Fall 2013 Lecture 7 (1 Of 2) 10/1/13

Front 1

Importance of cell body (of neuron)

Back 1

Contains genetic and metabolic machinery for neurotransmitter synthesis and organelles. Vital.

Front 2

Axon

Back 2

Propagates action potentials.

Front 3

Dendrites

Back 3

Axons of other neurons input signaling factors and neurotransmitters to dendrites.

Front 4

Synapse

Back 4

Space between axon terminal and neuron or other target tissue. Can occur on cell bodies, dendrites, or axons.

Front 5

Nomenclature for Peripheral Nervous System (PNS) cell bodies and axons

Back 5

Cell Body = Ganglion
Axon = Nerve

Front 6

Nomenclature for Central Nervous System (CNS) cell bodies and axons

Back 6

Cell Body = Nucleus
Axon = Tract

Front 7

All neurons in the PNS are surrounded by ________

Back 7

Glia (Schwann cells)

Front 8

Function of Schwann cells

Back 8

Surrounds (wraps around) all peripheral nerve axons and cell bodies. Thick layer of phospholipids = myelination. Protective.

Front 9

Nodes of Ranvier

Back 9

Gaps between cells where there is no myelination.

Front 10

What is Laminin?

Where found?

Back 10

Glycoprotein that promotes growth and regeneration of axons and glia. Found in basement membrane.

Front 11

Which type of connective tissue surrounds:

A) whole nerve
B) fascicles of nerve fibers
C) surrounds individual axons

Back 11

A) Epineurium
B) Perineurium
C) Endoneurium

Front 12

Forms a protein interface between Schwann cells and endoneurium.

Back 12

Basement membrane

Front 13

What type of cells secrete the protein matrix that makes up the basement membrane?

Back 13

Schwann cells

Front 14

Clusters of axons targeting single muscles or cutaneous (skin) regions are called __________

Back 14

Nerve fascicles

Front 15

T or F?

A single nerve has one or many fascicles that all innervate the same muscle or region.

Back 15

F

A nerve can have fascicles that separate out as individual nerves (ie femoral).

But True that nerves can have one or many fascicles.

Front 16

Nervi nervorum

Back 16

Bundles of axons innervating the CT layers of nerves (endoneurium, perineurium, and epineurium)

Front 17

Vasa nervorum

Back 17

local blood vessels to CT, axons and glia in nerves

Front 18

Guillain-Barre syndrome

Back 18

Demyelination of mostly motor fibers by auto-immune response to infection, surgery or immunization. Affects the PNS.

Front 19

A demyelination disease that affects the CNS.

Back 19

Multiple Sclerosis

Front 20

Negative symptoms of neuropathy

Back 20

Loss of sensation, muscle weakness, and atrophy.

Front 21

Positive symptoms of neuropathy

Back 21

Parasthesia (burning, tingling, tightness, or pins and needles)

Hyperalgesia (exaggerated pain perception in response to a normally painless stimulus)

Front 22

Causes of neural disease due to damage to axons or glial cells

Back 22

Diabetes, kidney failure, chronic alcoholism, nutritional deficiency, auto-immune disease, trauma

Front 23

Why is painful tingling the first sign of recovery from injury due to temporary compression of nerves?

Back 23

Slow conducting pain neurons are the first to recover from anoxia.

Front 24

What part of the neuron is necessary for nerve regeneration?

Back 24

Cell body.

Front 25

Axon plus Schwann cells (but not basement membrane), distal to injury undergo __________ and ________________

Back 25

Degeneration and Phagocytosis

Front 26

Which part of nerve regenerates by branching ("sprouting")?

Back 26

Axon proximal to injury

Front 27

What guides the axons during "sprouting"?

Back 27

Schwann cells create basement membrane tunnels (using laminin) that lead toward the target neurons. Axons sprout branches into these tunnels.

Front 28

Why is CNS re-growth minimal?

Back 28

Absence of basement membrane.

Front 29

Major neurite-promoting glycoprotein component of the basement membrane that is increased on the surface of Schwann cells and the luminal face of basement membrane following injury.

Back 29

Laminin

Front 30

Nerve growth factor (NGF) re-establishes connections. It is secreted by _________ cells and __________ cells.

Back 30

Schwann cells and target cells.

Front 31

What role do macrophages play in nerve regeneration?

Back 31

Helps to remove debris, specifically myelin and the damaged axon, from the distal injury site. Cleaning or clearing process before nerve regeneration that essentially prepares the distal stump for reinnervation.

Front 32

The H-shaped region in the spinal cord, with cell bodies, dendrites, and proximal axons.

Back 32

The gray matter, composed of ventral and dorsal horns.

Front 33

What causes white color of white matter of spinal cord?

Back 33

Myelin, the glial cells surrounding many axons, "whitens" the tissue.

Front 34

______________ pass longitudinally along spinal cord.

Back 34

Axons

Front 35

The spinal nerve is composed of bundles of axons that come from _________________________.

Back 35

Cell bodies in the ventral and dorsal horns

Front 36

Cluster of cell bodies of sensory neurons

Back 36

Dorsal root ganglion

Front 37

What does pseudo-unipolar mean?

Back 37

It contains an axon that has split into two branches; one branch runs to the periphery and the other to the spinal cord. Pseudounipolar neurons do not have dendrites.

Front 38

Dorsal ramus innervates

Back 38

deep back muscles and overlying skin

Front 39

Ventral ramus innervates

Back 39

remaining muscles, skin, etc.

Front 40

Peripheral Nervous System (PNS)

Back 40

Nerves outside the brain and spinal cord.

Front 41

What structure runs perpendicular to peripheral nerves, and is connected to peripheral nerves by gray and white rami.

Back 41

Sympathetic ganglia