Lecture 2: The Nervous System and Nervous Tissue

Question 1

3 functions of the nervous system (NS)

Answer 1

sensory input, integration, motor output

Question 2

________ is information gathered by sensory receptors about internal and external changes

Answer 2

Sensory input

Question 3

Interpretation of sensory input

Answer 3

Integration

Question 4

_______ is the activation of effector organs (muscles and glands) produces a response

Answer 4

Motor output

Question 5

The central nervous system consists of the __________ and it’s the integration and ____________

Answer 5

Brain and spinal cord; Command center

Question 6

Peripheral nervous system consists of paired _______ that carry messages to and from the CNS

Answer 6

Spinal and cranial nerves

Question 7

2 divisions of the nervous system

Answer 7

Sensory (afferent) and motor (efferent) division

Question 8

Motor division of the PNS consists of __________ and __________ nervous system

Answer 8

Somatic; Autonomic

Question 9

Somatic nervous system is __________, involving the

conscious control of skeletal muscles

Answer 9

Voluntary

Question 10

Autonomic nervous system is involuntary, regulating smooth muscle, cardiac muscle, and glands

Answer 10

Involuntary

Question 11

Autonomic nervous system consists of 2 subdivisions: _________ and __________

Answer 11

Sympathetic; Parasympathetic

Question 12

Two principal cell types of the NS

Answer 12

Neurons and Glial cells

Question 13

Excitable cells that transmit electrical signals

Answer 13

Neurons

Question 14

Supporting cells of the NS

Answer 14

Glial cells (neuroglia)

Question 15

6 types of glial cells

Answer 15

Astrocytes, microglia, ependymal cells, oilgodendrocytes, satellite cells, and schwann cells

Question 16

Astrocytes, microglia, ependymal cells, and oilgodendrocytes are part of the ______________

Answer 16

Central nervous system

Question 17

Satellite cells and schwann cells are part of the _______

Answer 17

Peripheral nervous system

Question 18

Most abundant in the CNS, versatile, and highly branched glial cells

Answer 18

Astrocytes

Question 19

Astrocytes guide ______ of young neurons and control the chemical environment

Answer 19

Migration

Question 20

_________ cells are defensive cells in the CNS; they migrate toward injured neurons and
phagocytize microorganisms and neuronal debris

Answer 20

Microglial

Question 21

________ cells line cerebrospinal fluid-filled cavities in the brain and spinal cord (CNS)

Answer 21

Ependymal

Question 22

________ are branched cells that have processes that form myelin sheaths around CNS nerve fibers

Answer 22

Oligodendrocytes

Question 23

_______ cells surround neuron cell bodies in the PNS

Answer 23

Satellite

Question 24

________ cells surround PNS nerve fibers and form myelin sheaths

Answer 24

Schwann

Question 25

Schwann cells are vital to __________ of damaged peripheral nerve fibers

Answer 25

Regeneration

Question 26

_________ are long-lived (100+ years)

Answer 26

Neurons

Question 27

Neurons have a high metabolic rate—depends on continuous supply of ______ and _______

Answer 27

Oxygen; Glucose

Question 28

Neuronal _________ functions in electrical signaling and cell-to-cell interactions during development

Answer 28

Plasma membrane

Question 29

The _________ is the biosynthetic center of a neuron

Answer 29

Cell body

Question 30

The cell body has a well-developed ____________ | and a network of neurofibrils (neurofilaments)

Answer 30

Golgi apparatus

Question 31

Cone-shaped area from which axon arises

Answer 31

Axon hillock

Question 32

Clusters of cell bodies are called nuclei in the CNS, and ______ in the PNS

Answer 32

Ganglia

Question 33

Processes consist of _______ and _______

Answer 33

Dendrites; Axons

Question 34

Bundles of processes are called tracts in the CNS, | and _______ in the PNS

Answer 34

Nerves

Question 35

_________ are the receptive (input) regions of a neuron that convey electrical signals toward the cell body as graded potentials

Answer 35

Dendrites

Question 36

Axon: Consist of long axons (nerve fibers) and occasional branches called ________

Answer 36

Axon collaterals

Question 37

Knoblike axon terminals

Answer 37

Synaptic knobs

Question 38

Secretory region of the neuron; release neurotransmitters to excite or inhibit other cells

Answer 38

Synaptic knobs

Question 39

The axon is the _________ region of a neuron that generates and transmits nerve impulses (action potentials) away from the cell body

Answer 39

Conducting

Question 40

Molecules and organelles are moved along axons by motor molecules in two directions, which are _________ and ___________

Answer 40

Anterograde; Retrograde

Question 41

Anterograde

Answer 41

Toward axonal terminal

Question 42

Retrograde

Answer 42

Toward the cell body

Question 43

Moves material by axoplasmic (cytoplasmic) flow at 0.2–2.5 mm/day

Answer 43

Slow axonal transport

Question 44

Moves organelles at rates of up to 400 mm/day

Answer 44

Fast axonal transport

Question 45

Forward (or anterograde) transport

Answer 45

From cell body to axon terminal

Question 46

Backward (or retrograde) transport

Answer 46

From axon terminal to cell body

Question 47

Segmented protein-lipoid sheath around most long or large-diameter axons

Answer 47

Myelin sheath

Question 48

The myelin sheath functions to protect and electrically _____ the axon and increase speed of ____________

Answer 48

Insulate; Nerve impulse transmission

Question 49

__________ wrap many times around the axon in the PNS

Answer 49

Schwann cells

Question 50

Peripheral bulge of Schwann cell cytoplasm

Answer 50

Neurilemma

Question 51

Myelin sheath gaps between adjacent Schwann cells; sites where axon collaterals can emerge

Answer 51

Nodes of Ranvier

Question 52

Thin nerve fibers are _______________ in the PNS

Answer 52

Unmyelinated

Question 53

One __________ may incompletely enclose 15 or more unmyelinated axons

Answer 53

Schwann cell

Question 54

Myelin sheaths in the CNS are formed by processes of ___________, not the whole cells (like in Schwann cell myelination)

Answer 54

Oligodendrocytes

Question 55

Nodes of Ranvier are present in CNS myelin sheaths, but there is no ________

Answer 55

Neurilemma

Question 56

Thinnest fibers are also _______ in the CNS

Answer 56

Unmyelinated

Question 57

Dense collections of myelinated fibers

Answer 57

White matter

Question 58

Consists mostly of neuron cell bodies and unmyelinated fibers

Answer 58

Gray matter

Question 59

3 "structural" types of neurons

Answer 59

Mulitpolar, Bipolar, Unipolar

Question 60

1 axon and several dendrites; Most abundant; Examples include motor neurons and interneurons

Answer 60

Multipolar

Question 61

1 axon and 1 dendrite (2 processes extend from the cell body); Rare; Example - retinal neurons

Answer 61

Bipolar

Question 62

Single, short process that has two branches: peripheral and central processes

Answer 62

Unipolar

Question 63

3 "functional" types of neurons

Answer 63

Sensory, Motor and Interneurons

Question 64

Transmit impulses from sensory receptors toward the CNS

Answer 64

Sensory (afferent) neurons

Question 65

Carry impulses from the CNS to effectors

Answer 65

Motor (efferent) neurons

Question 66

Shuttle signals through CNS pathways; most are entirely within the CNS

Answer 66

Interneurons (association neurons)

Question 67

Most multipolar neurons are what type of neurons?

Answer 67

Interneurons

Question 68

All bipolar neurons are what type of neurons?

Answer 68

Sensory neurons

Question 69

Most unipolar neurons are what type of neurons?

Answer 69

Sensory neurons

Question 70

Some multipolar neurons are what type of neurons?

Answer 70

Motor neurons