Ch. 11- Nervous System And Nervous Tissue

Question 0

Nuclei

Answer 0

Clusters of cell bodies in CNS

Question 1

7 major structures of the nervous system are…

Answer 1

1. Brain
2. 12 pair cranial nerves
3. Spinal cord
4. 31 pairs spinal nerves
5. Ganglia
6. Enteric plexuses
7. Sensory receptors

Question 2

Ganglia

Answer 2

Clusters if neuronal cell bodies in PNS

Question 3

Plexus

Answer 3

Net work of spinal nerve in PNS

Question 4

Tract

Answer 4

Bundles of neuron process (axon) in CNS

Question 5

Nerve

Answer 5

Bundles of neuron process (axon) in PNS

Question 6

CNS includes…

Answer 6

Brain and spinal cord (medulla to L2)

Question 7

Astrocytes (CNS)

Answer 7

Form blood-brain barrier by covering blood capillaries

Regulate K+ balance

Question 8

PNS contains…

Answer 8

Cranial and spinal nerves that contain both sensory and motor fibers. Connects CNS to muscles, glands & all sensory receptors

Question 9

Three subdivisions of PNS are…

Answer 9

1. Somatic (voluntary) nervous system (SNS)
2. Autonomic (involuntary) nervous system (ANS)
3. Enteric nervous system (ENS)

Question 10

Somatic (voluntary) nervous system

Answer 10

Sensory receptors to CNS.

Motor neurons to skeletal muscle tissue

Question 11

Autonomic (involuntary) nervous system

Answer 11

1. Sensory neurons from visceral organs to CNS
2. Motor neurons to smooth & cardiac muscle and glands
   
   • sympathetic and parasympathetic divisions

Question 12

Sympathetic division

Answer 12

Speeds up heart rate

Question 13

Parasympathetic division

Answer 13

Slows down heart rate

Question 14

Enteric nervous system

Answer 14

Involuntary sensory and motor neurons control GI TRACT

Question 15

What is a Neuron?

Answer 15

• Functional unit of nervous system.
• Have capacity to produce action potentials.
• single nucleus with prominent nucleolus

Question 16

Nissl bodies (chromatophilic substance)

Answer 16

Rough ER & RNA Ribosomes for protein synthesis.

Question 17

Neurofibrils

Answer 17

Intermediate neurofilaments. Gives cell shape and support

Question 18

2 parts of a neuron

Answer 18

1. Dendrite

2. Axon

Question 19

Dendrites

Answer 19

• Conducts impulse TOWARDS cell body.
• Short and unmyelinated
• contains neurofibrils (cytoskeleton) & nissl bodies

Question 20

Axons

Answer 20

• Conduct impulses AWAY from cell body.
• arises at axon hillock
• impulses arise from initial segment (trigger zone)

Question 21

Initial segment (trigger zone) of an axon

Answer 21

First portion of the axon

Question 22

Axon terminals

Answer 22

Fine processes where side branches (collaterals) end

Question 23

Synaptic end bulbs

Answer 23

Swollen tips on axon.

Contain vesicles filled with neurotransmitters

Question 24

Axoplasm

Answer 24

Cytoplasm of axon

Question 25

Axolemma

Answer 25

Plasm membrane of axon

Question 26

Colateral

Answer 26

Branch from axon

Question 27

Functional classification of neurons

Answer 27

1. Sensory (afferent) neurons 2. Motor (efferent) neurons 3. Interneurons (association) neurons

Question 28

Sensory (afferent) neurons

Answer 28

Transport sensory info from skin, muscles, joints, sense organs & viscera to CNS

Question 29

Motor (efferent) neurons

Answer 29

Send motor nerve impulses to muscles & glands

Question 30

Interneurons (association) neurons

Answer 30

Connects sensory to motor neurons | 90% of neurons in the body

Question 31

Structural classification of neurons

Answer 31

Based on number of processes found on body cell. 1. Multipolar 2. Bipolar 3. Unipolar

Question 32

Multipolar neurons

Answer 32

Several dendrites & one axon. Most common cell type

Question 33

Bipolar neurons

Answer 33

One main dendrite and one axon found in retina, inner ear & olfactory

Question 34

Unipolar neurons

Answer 34

One process only (develops from bipolar). ALWAYS SENSORY NEURONS

Question 35

Neuroglial (glia) cells

Answer 35

Rapid mitosis in tumor formation (gliomas). 4 types in CNS 2 types in PNS

Question 36

Four types of neuroglial cells in CNS

Answer 36

1. Astrocytes 2. Oligodendrocytes 3. Microglia 4. Ependymal

Question 37

Olgiodendrocytes (CNS)

Answer 37

Most common glial cell type Forms myelin sheath around more than one axons in CNS

Question 38

Microglia (CNS)

Answer 38

Small cells found near blood vessels Phagocyte role (clear away dead cells)

Question 39

Ependymal (CNS)

Answer 39

Form epithelial membrane lining ventricles and central canals Produces CSF part of choroid a plexuses Simple cuboidal epithelium with cilia

Question 40

Satellite cells (PNS)

Answer 40

Supports neurons in the PNS ganglia

Question 41

Schwann cell (PNS)

Answer 41

Cells encircling PNS axons Produces part of the myelin sheath surrounding an axon in the PNS All axons surrounded by a LIPID & PROTEIN coverin (myelin sheath) produced by Schwann cells Neurolemma (Neurilemma) is cytoplasm & nucleus of Schwann cell Gaps called nodes of Ranvier Myelinated fibers appear white

Question 42

Two types of neuroglial cells in PNS

Answer 42

1. Schwann | 2. Satellite cells

Question 43

How is action potential transmitted

Answer 43

Dendrite receive stimulus- cell body, axon hillock, axon terminal, synapse bulb & vesicles, release neurotransmitter, effector start action potential at axon hillock

Question 44

Cause of Parkinson's

Answer 44

Due to degeneration of dopamine, involuntary muscle contractions

Question 45

Epilepsy

Answer 45

Second most common neurological disorder. Characterized by short, reoccurring attacks initiated by electrical discharges in the brain. LOC. Skeletal muscles may contract involuntarily

Question 46

Multiple sclerosis

Answer 46

Autoimmune disorder causing destruction of myelin sheaths in CNS

Question 47

Myelination in PNS

Answer 47

Schwann cells myelinated (wrap around) axons in the PNS during fetal development

Question 48

Myelination in the CNS

Answer 48

Olgiodendrytes myelinate axons in the CNS no Neurilemma is formed.

Question 49

White matter

Answer 49

Myelinated axon (white in color)

Question 50

Gray matter

Answer 50

NERVE CELL BODIES, dendrites, axon terminals, bundles of UNMYELINATED AXONS AND NEUROGLIA (gray matter)