neurohistology

Question 1

synapse

Answer 1

space between 2 neurons where communication occurs

Question 2

gap junctions

Answer 2

connect two neurons together; allow electrical signal to pass from 1 to another without a synapse

Question 3

categories of nerve cells

Answer 3

• conducting elements
• supportive cell types

Question 4

conducting elements

Answer 4

excitable cells; neurons; typically conduct electrical signals over long distances

Question 5

supportive cell types

Answer 5

glial cells (neuroglia, glia); do not generate/conduct electrical signals but facilitate the transmission of these signals in conductive elements

Question 6

cell body

Answer 6

contains the nucleus, surrounded by cytoplasm

Question 7

nucleus

Answer 7

contains chromosomes (DNA)

Question 8

nucleolus

Answer 8

produces ribosomes (important for growth and development of neuron)

Question 9

ribosomes

Answer 9

site of protein synthesis or translation in all cells

Question 10

mitochondria

Answer 10

powerhouse of the cell

Question 11

Golgi apparatus

Answer 11

type of endoplasmic reticulum
- role in making sure proteins are created

Question 12

axon

Answer 12

carries the electrical signal; typically single axon but can have branches

Question 13

axon hillock

Answer 13

where the axon initiates from the cell body (electrical signal starts here)

Question 14

dendrites

Answer 14

• Arise from the cell body; multiple branches
• primary targets for synaptic inputs from other neurons
• contain a lot of ribosomes; contain specialized cytoskeletal proteins

Question 15

nissl bodies

Answer 15

clusters of rough endoplasmic reticulum
- make proteins and replace growth and regenerating

Question 16

neurofibrils

Answer 16

cell shape and support

Question 17

microtubules

Answer 17

allow movement of materials to/from cell body

Question 18

transport

Answer 18

organelles can be moved along the neuron

Question 19

slow axonal transport

Answer 19

1-5 mm/day; unidirectional; axoplasm supply
- away from cell body

Question 20

fast axonal transport

Answer 20

200-400 mm/day; to and from cell body
- bidirectional
- bring garbage cells up to be recycled and bring down new

Question 21

convergence

Answer 21

reflects the number of inputs to a single neuron
- coming in
- receive input from more than one location

Question 22

divergence

Answer 22

reflects the number of targets that 1 neuron innervates
- going out

Question 23

bipolar

Answer 23

2 ends (1 axon, 1 dendrite)

Question 24

unipolar

Answer 24

1 axon, no dendrites

Question 25

multipolar

Answer 25

several dendrites, 1 primary axon

Question 26

receptors

Answer 26

sense something (sensory)

Question 27

afferents

Answer 27

carry single away from periphery to CNS (dorsal)

Question 28

integrating centers

Answer 28

integrate/figure out what info means

Question 29

internuncial neurons (interneurons)

Answer 29

connect neurons (relay point)

Question 30

efferents

Answer 30

carry info away from CNS to periphery

Question 31

effectors

Answer 31

target cells, number of types of tissue (endocrine glands, muscles, etc)

Question 32

presynaptic neuron

Answer 32

sending the message

Question 33

postsynaptic neuron

Answer 33

receiving the message

Question 34

synaptic cleft

Answer 34

space between the presynaptic and postsynaptic neurons - support cells within space that help neurotransmitter across

Question 35

interneurons

Answer 35

short neurons that connect other neurons - only found in CNS

Question 36

projection neurons

Answer 36

longer neurons that carry signals over significant distances - travel long distance

Question 37

glial cells

Answer 37

- supportive cells - still vital - only stem cells in the adult brain

Question 38

glial cells function

Answer 38

- regulate ions in the nervous system - influence signal transduction in nerve cells - control neurotransmitter reuptake and processing at / near synaptic cleft - provide framework for growth of neural tissue during development - play a role in neural recovery from injury - brain-immune system interface - cycles interstitial fluid through the brain during sleep

Question 39

primary types of glial cells

Answer 39

- astrocytes - oligodendrocytes - microglial cells

Question 40

glial stem cells

Answer 40

- subset of astrocytes - polydendrocytes

Question 41

astrocytes

Answer 41

found in the CNS

Question 42

astrocytes function

Answer 42

- blood brain barrier - ensure appropriate chemical environment for neuronal signaling - formation of new synapses

Question 43

oligodendrocytes

Answer 43

only found in CNS

Question 44

oligodendrocytes function

Answer 44

- produce myelin - stops electrical signal from leaking out - speeds up transmission of electrical signals

Question 45

Schwann cells

Answer 45

the cells in the PNS that produce myelin

Question 46

microglial cells

Answer 46

- important when injury / damage occurs - signal to other cells to modulate inflammatory response

Question 47

subset of astrocytes

Answer 47

- mostly located near the ventricles of the brain or near the blood vessels around the ventricles

Question 48

polydendrocytes

Answer 48

- produce mature oligodendrocytes and some astrocytes

Question 49

ganglia

Answer 49

group of nerve cell bodies and supporting cells

Question 50

nerves

Answer 50

groups of peripheral axons

Question 51

sensory systems

Answer 51

- receive and process internal (movement) and external (touch, vibration, pain, temp) stimuli - peripheral and central nervous system components

Question 52

motor systems

Answer 52

- generate movement - usually, but not always, in response to sensory stimuli

Question 53

association systems

Answer 53

- "relay" center - process/integrate signals from sensory and motor systems, send them on to the appropriate area

Question 54

somatic motor division

Answer 54

connect brain/spinal cord to skeletal muscle

Question 55

visceral/autonomic motor divison

Answer 55

innervates smooth muscle, cardiac muscle, glands (involuntary)

Question 56

autonomic ganglia

Answer 56

site of synapses between CNS visceral motor neurons and peripheral motor neurons

Question 57

sympathetic division

Answer 57

ganglia located near the spinal column

Question 58

parasympathetic divison

Answer 58

ganglia located near the organs they innervate

Question 59

enteric system

Answer 59

gut innervation