Nervous Tissue

Front 1

What are the two divisions of the nervous system?

Back 1

Central Nervous System (CNS) and Peripheral Nervous System (PNS)

Front 2

What are the two components of the CNS?

Back 2

Brain and spinal cord

Front 3

Describe the three divisions of the PNS.

Back 3

1. Sensory/Motor Divisions

2. Visceral/Somatic sensory divisions and Visceral/Somatic motor divisions

3. Sympathetic/Parasympathetic Division (branches out from Visceral motor division)

Front 4

Neurons

Back 4

Conduct action potentials (only ones to do this)

Front 5

Neuroglia

Back 5

Nervous connective tissue; support cells

Front 6

What are the two major cell types of the CNS?

Back 6

Neurons and Neuroglia

Front 7

What are the parts of the PNS?

Back 7

All the parts of the nervous system except for the brain and spinal cord

Front 8

What is a nerve fiber?

Back 8

Axon

Front 9

What is a nerve?

Back 9

Bundle of nerve fibers (axons) wrapped in fibrous connective tissue

Front 10

What are the connective tissue wrappings of a nerve, from superficial to deep, and what does each encase?

Back 10

Epineurium- surrounds entire nerve

Perineurium- surrounds bundle of fibers (fascicle)

Endoneurium- surrounds single fiber

Front 11

What is tract?

Back 11

Bundle of fibers in the CNS (no connective tissue)

Front 12

What is a ganglion?

Back 12

Grouping of neuronal cell bodies outside the CNS

Front 13

What is the nucleus?

Back 13

Grouping of neuronal cell bodies within the CNS

Front 14

What is grey matter?

Back 14

Nuclei in the CNS plus unmyelinated axons and neuroglia

Front 15

What is white matter?

Back 15

Tracts (myelinated axons) in CNS

Front 16

What would be the path of a needle inserted into a peripheral nerve that pierces the axoplasm?

Back 16

1. Nerve Fiber

2. Nerve

3. Tract

4. Ganglion

5. Nucleus

6. Gray Matter

7. White Matter

Front 17

Describe the function of the sensory (afferent) division of the PNS.

Back 17

Carries sensory signals from receptors

Front 18

What is a receptor?

Back 18

A cell specialized to detect a stimulus

Front 19

Describe the function of the somatic sensory division of the PNS.

Back 19

Carries signals from receptors in the skin, muscles, bones, and joints

Front 20

Describe the function of the visceral sensory division of the PNS.

Back 20

Carries signals from the viscera of the thorax and abdomen; such as heart, lungs, stomach, and urinary bladder

Front 21

Describe the function of the motor (efferent) division of the PNS.

Back 21

Carries signals from the CNS to the glands and muscles of the body

Front 22

Describe the function of the somatic motor division of the PNS.

Back 22

Carries signals to the skeletal muscles (its effeter organs) causing muscle contraction

Front 23

Describe the function of the visceral motor division of the PNS.

Back 23

Also called the Autonomic Nervous System (ANS); carries signals to glands, cardiac muscle, and smooth muscle (it's effector organs) and operates automatically (no voluntary control)

Front 24

What are the two subdivisions of the visceral motor division?

Back 24

Sympathetic and Parasympathetic

Front 25

Describe the sympathetic division of the visceral motor division.

Back 25

(Fight-or-flight); activated in emergencies. Can speed up heart rate or slow down digestion

Front 26

Describe the parasympathetic division of the visceral motor division.

Back 26

Rest-and-digest)Activated when resting. Slows down heart rate and speeds up digestion

Front 27

What are the three universal properties of neurons?

Back 27

Excitability, conductivity, and secretion

Front 28

What are the three functional categories used to classify neurons?

Back 28

Sensory (afferent) neurons, Interneurons (association neurons), and Motor (efferent) neurons

Front 29

Describe sensory (afferent) neurons.

Back 29

Detect stimuli such as light, heat, pressure, and chemicals and transmit information about them to the CNS

Front 30

What does afferent refer to?

Back 30

Sending signals toward the CNS

Front 31

Describe interneurons (association neurons).

Back 31

Make up 90% of all neurons; lie entirely in CNS; receive signals from other neurons; integration (process, store, and retrieve information; and makes decisions in response to stimuli)

Front 32

Describe motor (efferent) neurons.

Back 32

Carry signals to muscles and glands from the CNS

Front 33

What does efferent refer to?

Back 33

Sending signals from the CNS

Front 34

What is the neurosoma (soma or cell body )?

Back 34

Control center; contains organelles: neurofibrils and nissl bodies

Front 35

What are neurofibrils?

Back 35

Intermediate filaments (actin) of cytoskeleton that compartmentalize rough endoplasmic reticulum into nissl bodies

Front 36

What are nissl bodies?

Back 36

Dark staining regions in neuron

Front 37

Describe the structure and function of a dendrite.

Back 37

Carry information to soma and receives signals from other neurons; are short, highly branched, unmyelinated; their can be thousands on just one neuron

Front 38

Describe the structure and function of an axon.

Back 38

Long fiber with no nissl bodies that originates at the axon hillock; 1 axon per neuron; sends signals to points remote/away from soma and conducts nerve signals called action potentials

Front 39

What is axoplasm?

Back 39

Cytoplasm of an axon

Front 40

What is axolemma?

Back 40

Plasma membrane of an axon

Front 41

What is an axon collateral?

Back 41

Branch off of the main axon that usually feeds back onto the soma

Front 42

What are the four structural categories of neurons?

Back 42

Multipolar, bipolar, unipolar, and anaxonic

Front 43

Describe multipolar.

Back 43

One axon and two or more dendrites; most CNS neurons and somatic motor neurons

Front 44

Describe bipolar.

Back 44

One axon and one dendrite; usually retina, inner ear, and olfactory cells

Front 45

Describe unipolar.

Back 45

Only one process from soma which branches; always sensory

Front 46

Describe anaxonic.

Back 46

Multiple dendrites and no axon; usually found in the brain, retina, and adrenal medulla

Front 47

Differentiate between neurons and neuroglia.

Back 47

Neuroglia are the support cells; cannot transmit action potentials (neurons); neuroglia can divide and multiply (source of brain tumors); outnumber neurons

Front 48

What are the six types of neuroglia?

Back 48

Oligodendrocytes, ependymal cells, microglia, astrocytes, schwann cells (neurilemmocytes), and satellite cells

Front 49

Describe the location and function of an oligodendrocyte.

Back 49

CNS; form myelin in brain and spinal cord; form supporting network

Front 50

Describe the location, appearance, and function of epedymal cells.

Back 50

CNS; epithelial cells; line ventricles and central canal; create and circulate cerebrospinal fluid

Front 51

Describe the location, appearance, and function of microglia.

Back 51

CNS; derived from white blood cells; small macrophages that phagocytize and destroy microorganisms, foreign matter, and dead nervous tissue

Front 52

Describe the location, appearance, and function of astrocytes, the largest and most common glial cell.

Back 52

CNS; form blood-brain barrier and cover brain surface and nonsynaptic areas in grey matter; form support network by linking neurons to blood vessels; convert blood glucose to lactate to nourish neurons; secrete growth proteins to promote neuron growth and synapse formulation; form scar tissue in CNS when neurons die

Front 53

Describe the location, appearance, and function of schwann cells (neurilemmocytes).

Back 53

PNS; produce myelin sheath; encloses unmyelinated axons; aids in regeneration of damages to peripheral nerves

Front 54

Describe the location, appearance, and function of satellite cells.

Back 54

PNS; small, support cells in ganglia; surround somas of neurons in ganglia of PNS

Front 55

What are the functions of the myelin sheath?

Back 55

Electrically insulates axons, increases speed of conduction, and decreases energy needed for conduction

Front 56

Describe the formation of the myelin sheath in the CNS.

Back 56

Formed by oligodendrocytes; myelinates more than one nerve fiber; no neurilemma

Front 57

Describe the formation of the myelin sheath in the PNS.

Back 57

Formed by Schwann cells (neurilemmacytes); the myelin sheath is compacted membranes of Schwann cells; myelinates one nerve fiber; neurilemma=outer layer of cytoplasm and nucleus of Schwann cell; Node of Ranvier=bare axolemma

Front 58

What are Nodes of Ranvier?

Back 58

Gaps between adjacent Schwaan cells or oligodendrocytes (no myelin); found in both CNS and PNS

Front 59

What are internodes?

Back 59

Myelin-covered segments of axon; found in CNS and PNS

Front 60

Ad

Back 60

Toward

Front 61

Af

Back 61

Toward

Front 62

Arbor

Back 62

Tree-like

Front 63

Astro

Back 63

Star

Front 64

Axo

Back 64

Axon, axis

Front 65

Dendro

Back 65

Tree

Front 66

Ef

Back 66

Out, away

Front 67

Ependyma

Back 67

Upper garment

Front 68

Fer

Back 68

To carry

Front 69

Glia

Back 69

Glue

Front 70

Inter

Back 70

Between

Front 71

Lemma

Back 71

Husk, sheath, peel

Front 72

Micro

Back 72

Small

Front 73

Oligo

Back 73

Few

Front 74

Somat

Back 74

Body