Neuro Exam 1.3
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Neuro Exam 1.3
review of lecture 3 for neuro exam 1
a type of nervous system cell
Are neurons capable of conducting an impulse?
Neurons conduct impulses in the form of what?
What other cells can produce action potentials?
How many neurons are in the body?
Neurons are heterogenous:
take many different forms, but basically function the same
What is a soma?
cell body of a neuron
Describe the cell body of a neuron:
fairly large (4-135 microns in diameter)
shape varies (heterogenous)
contents are similar to that of other cells in the body
What are the characteristics of the cell body/neuronal cell of a neuron?
non-nuclear structures (cellular organelles)
mitochondria (power house)
rough endoplasmic reticulum
smooth endoplasmic reticulum
golgi apparatus (golgi body)
middle of cell body
If the nucleus is not in the middle of the cell body, the cell is considered:
Is the nucleus large or small?
What is the shape of the nucleus?
The nucleus has a nuclear membrane (envelope) with a distinct:
What allow for passage of large macromolecules back and forth w/ cytoplasm through the nuclear membrane of a neuron?
What is the nuclear membrane continuous w/?
What is contained in the nucleus?
46 chromosomes and DNA
Where does DNA undergo transcription for mRNA?
in the nuclues
Where does translation occur?
rough ER in cytosol
Where does protein synthesis occur?
rough ER in cytosol
large inclusion w/in the nucleus where ribosomal RNA is synthesized and produced
What is rRNA involved w/ and where?
involved w/ protein synthesis at ribosome
Non-nuclear structures (cellular organelles):
can malfunction in neurons
What is the power house of a neuron?
Where are mitochondria found?
in the cytoplasm scattered throughout cell body
What are mitochondria involved with?
engergy production (ADP -> ATP)
What can neurons use for energy?
only glucose or glucose products (will not utilize fats or amino acids to make energy)
What chemical does the mitochondria require?
Can neurons store glycogen?
no, but skeletal muscle can
once energy supply is gone, there is no more energy (unconsciousness)
What is utilized during cellular respiration?
double membrane-bound vesicles that contain hydrolytic enzymes (50 or more)
What is the function of lysosomes?
digest things w/in cell [substances that orignate in and out of cell]
What are two ways that lysosomes can do to cause cell death?
lysosomes rupture and digest contents of cell (self-digesting)
pre-programmed cell breakdown (natural prosses in which cells are programmed to die off)
genetically determined cellular self-destruction process
What is another name for Rough Endoplasmic reticulum?
What is the rough endoplasmic reticulum?
a bunch of ribosomes
flattened, double-layered membrane structures lined w/ ribosomes giving it rough appearance
very active part of cytoplasm
Where is the rough endoplasmic reticulum located?
cell body and dendrites (close to nucleus)
What occurs in the rough ER?
Translation and synthesis
What general proteins are involved with translation and synthesis of the rough ER?
enzymes: hundreds needed for cells to work
What structural components are involved with translation and synthesis in the rough ER?
What other proteins are involved in translation and synthesis in the rough ER?
plasma membrane proteins
neuro-transmitters and neuro-modulators
The rough ER is the site of:
The smooth ER is a continuation of:
Does the smooth ER contain ribosomes?
no, therefore, it is smooth
What is the function of the smooth ER?
to channel proteins produced in the Rough ER to the golgi apparatus
What is another name for golgi apparatus?
What is the golgi apparatus?
double-membrane, flattened channels (sometimes a sac-like appearance)
What is the function of the golgi apparatus?
receive products (protein molecules) from smooth ER
modify, sort, and package protein molecules into specific membrane-enclosed vesicles
then migrate to where they are needed
The packaged protein molecules from the golgi apparatus can go to:
cell membrane regions for growth (contains growth protein)
lysosome (contains hydrolytic enzyme)
forms neuro tubular to be transported elsewhere
What normally causes diseased w/ golgi apparatus?
Nucleus (DNA) -> cytosol (cytoplasm) -> rough ER -> smooth ER -> golgi apparatus ->
cell membrane regions, lysosomes, neurotubules, numerous types of vesicles, etc.
What is the function of the cytoskeleton?
gives integrity to cells
forms shape and gives support to neuron
Is the cytoskeleton an organelle?
Where is the cytoskeleton found?
What 3 fibular organelles (protein molecules) make up the cytoskeleton?
What makes up microfilaments?
primarily actin (protein molecules) --smalles in diameter
Where is actin found?
axoplasm of the neuron in the axon
close to cell membrane
lots in growth cone
How many microfilaments does each neuron have?
they are in constant flux (some days you have more, some less) due to inconsistencies in the size of the cell bodies
When there is less actin, does this change the form of the cell?
less actin causes cell shape to be smaller, but the basic form is still there
Growth cone production:
as dendrites grow throughout development, so neuron can get from point a->b
What is another name for microtubules?
What are microtubules?
fibular organelle that makes the cytoskeleton
long tubular structures that form tracts to transport metabolites, vesicles, and ions
found in microtubules
molecule proteins, largest of the 3 fibrillar proteins (25nm in diameter)
Where are microtubules located?
cytoplasm, axon, and dendrites
What are microtubules very important to?
axonal transport mechanism
What is another name for neurofilaments?
What is the most abundant of fibrillar proteins?
Where are neurofilaments found?
in axons-neurofilament protein
oriented along the axis of the axon (run parallel)
What is the function of neurofilaments?
add strength (resiliency) and diameter (caliber) to axon
What is the diameter of a neurofilament?
When neurofilaments are defected, they cause what disease?
Microscopically, neurofilaments are seen as clumps in cells of which parts of the brain?
What is the Axonal Transport System?
transportation of substances from cell body to cellular processes and conversely utilizing microtubules
What are the two directions that the axonal transport system can take?
What is another name for anterograde?
transport away from cell body to the cellular processes (efferent)
transport from cellular process towards cell body (afferent)
What are the two rates that the axonal transport system work at?
Fast axonal transport system:
200-400mm per day
both anterograde and retrograde (16in/day)
Slow axonal transport system:
1-5 mm per day
only in anterograde
What movement direction and speed combonations are found in the axonal transport system?
NO slow retrograde...
What molecules travel the axonal transport system during fast anterograde?
plasma membrane components
synaptic vesicles containing neurotransmitter
What molecules travel the axonal transport system during fast retrograde?
vesicles and molecules
: nerve growth factor and other trophic molecules
What molecules travel the axonal transport system during slow anterograde?
proteins for regeneration
proteins to renew cytoskeleton and plasma membranes (actin)
What are force-generating motor proteins?
drives axonal transport system
how material is transported along neurotubules
What are the two categories of force-generating motor proteins?
protein molecule for anterograde movement
protein molecule for retrograde moement
What is the energy source for the force-generating motor proteins?
How do the force generating motor proteins work?
bind substance to be transported to neurotubule
neurotubule acts as a guide through the axon
What are the 3 options for movement of the force-generating proteins in the axonal transport system?
1. can pass another vesicle moving in the same direction on the same neurotubule
2. two vesicles can move bi-directional (opposite directions) on the same neurotubule
3. vesicles can shift b/w adjacent neurotubules