Cellular Neuroscience-Exam I

Question 1

How many cells are in the human brain?

Answer 1

170 Billion Cells HOW DO THEY KNOW THIS??

Question 2

What protein structures are used in axoplasmic transport?

Answer 2

MicroTubules and MicroFilaments

Question 3

Which cell structure accounts for over 90% of the cell surface area for synapses?

Answer 3

Dendrites

Question 4

What is a common example of an umyenated axon?

Answer 4

A pain receptor, thank god it takes these signals longer eh?

Question 5

What is an axon branch called?

Answer 5

An axon collateral

Question 6

What part of the axon contains the N.T. vesicles?

Answer 6

The axon terminal

Question 7

What determines the action of a neuron? The N.T. or the Receptor? Example??

Answer 7

The receptor determines the action for the neuron.. Ach excitatory in skeletal muscle, but inhibitory in cardiac muscle

Question 8

Will Negative Ion channels depolarize(excite) or hyperpolarize(inhibit) a neuron?

Answer 8

Hyperpolarize(Inhibit)

Question 9

Will positive ion channels depolarize (excite) or hyper polarize(inhibit) a cell?

Answer 9

Depolarize (Excite)

Question 10

Where am I going to find pseudo unipolar neurons? What makes them UNIQUE?

Answer 10

PNS Sensory Afferents…2 AXONS!!

Question 11

Where am I going to find BiPolar neurons?

Answer 11

Special Sensory. BiPolar people are special :)

Question 12

What is unique about multipolar neurons?

Answer 12

Large Dentritic Trees, perkunjie fibers

Question 13

What type of neuron makes up 99% of ALL NEURONS… wow. Where can I find these bad boys?

Answer 13

Interneurons, making connections between the afferent and efferent neurons, processing…ONLY IN CNS

Question 14

What are two main names for congregations of neuronal cell bodies(gray matter)?

Answer 14

Nuclei and ganglia

Question 15

What are 4 names to describe groups of axons(white matter)? Ready for some crazy new words?!

Answer 15

Tract, Fasciculus, lemniscus…several tracts=funiculus

Question 16

What types of glial cells might be excitable?

Answer 16

AstroCytes

Question 17

What are the main immune-like, and healing functions of Astrocytes?

Answer 17

The Blood Brain Barrier!! and scar formation in CNS

Question 18

What CNS glial cells line cavities?

Answer 18

EP-EN-DY-MAL cells

Question 19

What are the macrophages of the CNS?

Answer 19

MicroGlia

Question 20

What is the function of nonmyleinating schwann cells?

Answer 20

regrowth of motor axons in PNS

Question 21

What part of the PNS neuron does the Satellite cell surround?

Answer 21

The cell body

Question 22

What is an astrocytoma that can spread from one side of the brain to the other using the corpus callosum? PLEASE don’t get this wrong!

Answer 22

GlioBlastoma MultiForme

Question 23

What is the normal resting potential range of a neuron?

Answer 23

-70 to -90 mv

Question 24

What are the normal Na and K [Gradients]?

Answer 24

More Na outside cell, more K inside cell (Na/K pump-2 K in 3Na out)

Question 25

At rest which ion is the cell more permeable to Na or K?

Answer 25

K

Question 26

What is happening when a cells membrane potential only moves a little and gets more positive(like from -70mv to -60mv)?

Answer 26

Excitatory Post Synaptic Potential (E.P.S.P)!!!

Question 27

What's it called when a cell potential becomes slightly more negative (like -70mv to -80mv)?

Answer 27

Inhibitory Post Synaptic Potential (I.P.S.P)

Question 28

What is the A.P. threshold?

Answer 28

-55mv

Question 29

What are the two ways a nerve or muscle cell can be excited?

Answer 29

Synaptic Input OR Electrical Stimulation

Question 30

What is the first step after the threshold has been reached? What does the membrane potential reach?

Answer 30

Na channels open. Membrane potential will reach +20mv c/o all the positive Na's coming in

Question 31

What are two factors that open a Na channel?

Answer 31

Time and Voltage

Question 32

What event occurs to REpolarize the cell?

Answer 32

K will rush out naturally (we need to get the Positive charge out!)

Question 33

What do astrocytes in the CNS do to help maintain resting membrane potentials?

Answer 33

They Eat bananas! I mean potassium.

Question 34

What causes Myotonia congenita and spasticity?

Answer 34

Plateau Potentials c/o Calcium enrtry

Question 35

Why is the axon hillock the site of starting the A.P. propagation?

Answer 35

The hillock has the highest density of voltage gated channels

Question 36

What are the two types of A.P. propagation? Hint: has to do with myelin..

Answer 36

Local Current Flow & Saltatory Conduction

Question 37

How fast is a myelinated A.P. in mph? How much faster is that then unmyelinated?

Answer 37

360mph!! 50x faster

Question 38

Which conducts an action potential faster? Larger or smaller axon?

Answer 38

Larger Axons, less RESISTANCE!! I love electricity :)

Question 39

Which is normal conduction? Orthodromic or Antidromic?

Answer 39

Ortho=normal, Anti=not normal, made in a lab

Question 40

What type of sandwich are the synaptic transmission signals?

Answer 40

Signals at the synaptic transmission go from an electrical to a chemical, to an electrical sandwich :)

Question 41

Are synapses in the Soma (axo-somatic) generally E.P.S.P.'s or I.P.S.P.'s? What about ado-dendritic?

Answer 41

axo-somal: IPSP axo-dendritic: EPSP

Question 42

What type of channels open in the axon terminal to later on release N.T.?

Answer 42

Voltage gated Calcium Channels (Ca then flows down [gradient]

Question 43

What are the three main ways to end a synaptic transmission?

Answer 43

Diffusion, Enzyme degredation, or reup

Question 44

What never happens at the synapse of an alpha motor neuron and a motor neuron? What helps a muscle cell relax then?

Answer 44

IPSP.. IPSPs can happen at the dendrite or soma of the alpha motor neuron in the brain (just not at the axon terminal)

Question 45

What term is used for an axo-axonic synapse that aids another axon to release MORE neurotransmitter? What about the same thing but inhibiting?

Answer 45

Presynaptic Facilitation....vs Presynaptic Inhibition

Question 46

What are the 5 classy classes of N.T.'s?

Answer 46

1.MonoAmines 2. Cholinergic 3. Amino Acids 4. NeuroPeptides 5.NonTraditional

Question 47

What are the two classy classes of Receptors? What are their main functions?

Answer 47

Ion-To-Tropic & Metab-O-Tropic (Gprotein)....Iontotopic opens ion channels, metabotropic causes the chain rxn of Gproteins which can be EPSP,IPSP gene signaling YOU NAME IT

Question 48

What are the subcategories of MonoAmines?

Answer 48

1.Cat-E-Chol-Amines: a)Epi, b)NorEpi, c)Dopamine & 2.Seratonin

Question 49

What is an example of a Cho-Lin-Ergic N.T.?

Answer 49

Ace-tyl-cho-line

Question 50

What are three examples of Amino Acid N.T.'s?

Answer 50

a) Gamma-Amino-Butyric-Acid (GABA) b)Glycine c)Glutamate

Question 51

What are 3 examples of Neruo-peptides?

Answer 51

Endorphins, Calcitonin, Substance P

Question 52

What are two examples of nontraditional N.T.'s?

Answer 52

NO, and CO2

Question 53

What are the only two N.T.'s that are not BOTH IontoTropic AND MetaboTropic?

Answer 53

NorEpi & Dopamine