The Human Brain and Nervous Systems : Cells Flashcards
What 2 cells make up the Nervous System?
- Neurons
2. Glial
What are Neurons?
How many?
basic element in the nervous system
80-100 billlion in CNS and PNS
What are the Glial Cells?
Support for the Neurons
What Is the main role of the Glial Cell ?
Produce Myelin
What Is the 7 main role of the Glial Cell ?
- Support
- Produce Myelin
- Remove Debris
- Housekeeping
- neuron placement
- help form the blood brain barrier
- nourish the neurons
What are the most important 5 Glial cells in the CNS?
- Astrocytes
- Oligodendrocytes
- microglia
- Schwann
- satellite cells
what is Astrocytes ?
nourishes the Neurons
protects against injury
tigers Synapse
CNS
what is the Oligodendrocytes ?
Producing Myelin in CNS
what is microglia?
Acting like an immune system
what is Schwann ?
Producing Myelin in PNS
what is satellite cells ?
nourishes the Neurons
protects against injury
tigers Synapse
in PNS
what is Myline Made of ?
70 - lipid
30 - protein
what are Nodes of Ranvier ?
when there is no myelin on the axon
what does Nodes of Ranvier do?
Gives the Neuron the ability and speed to transmit electrical signal
Where are Neuron-transmitters stored?
Terminal Bottoms
What are the 4 types of neurons?
- interneurons
- multipolar nuerons
- unipolar nuerons
- Bipolar
what is interneurons ?
it connect the Neurons together
what is multipolar neurons ?
Multiple dendrite
1 long axon
mostly in the brain cortex
What is unipolar neurons ?
Seen in Sensory area
1 axon or 1 dendrite
what is Bipolar ?
Hearing / Vision / smell
1 axon and 1 dendrite
What is Synapse and when does it happen?
it is communication/ the transmission of information from neuron to neuron
GA 5 months to birth
What happens during pre Synapse?
the end of the axons are called Terminal bottoms and that is where the neurotransmitters are stored in vesicles
what happens during Synapse?
it triggers the vesicles to open
Neurotransmitters are released
where are the Neurotransmitters released ?
Synaptic cleft
what is the Synaptic cleft ?
the spaces between pre/ post Synapse
what are 3 ways Synapse impacts neurons ?
- exiting them
- inhabiting
- regulating
what are 7 examples of neurotransmitters?
- acetylcholine
- glutamate
- gaba
- dopamine
- epinephrine
- norepinephrine
- serotonin
what is acetylcholine ?
exiting
contracting the muscles PNS
what is glutamate?
exiting
Fight / flight CNS
what is GaBA?
inhabits
CNS sleep
what is Dopamine?
motor control
brain reward system
what is epinephrine ?
Excites
Heart rate
Flight Flight response
what is norepinephrine ?
attention, alertness, mood
What is serotonin ?
Exited/ inhabits
nervous system
what are the two phases of communication?
- Electrical
2. Chemical
what is in the electrical phase?
- Axons
2. Dendrites
what is in the Chemical phase?
- neurotransmitters
2. Synaptic cleft
what are the 4 steps of neuron function?
- polarization
- Chemical Transmission
2B. Electrical firing - Repolarization
what is the other name for polarization ?
Resting Membrane potential
what happens during polarization ?
- not transmitting
2. action energy
what is the action energy due to in polarization ?
- more sodium on the outside
K on the inside - Negative charge
what is the charge during polarization ?
Negative 70 Mv
What happens during Chemical Firing?
- neuron ready to fire — Synapse occurs
- neurotransmitters are released
- neurotransmitters attack to receptors
What happens during Electrical firing?
- protein Chanels open to allow the NA in to the Cell making it Positive
PASSIVE TRANSPORT
- Reaches action potential
What happens during Repolarization ?
- re establish the gradients to equal
- ACTIVE TRANSPORT
the NA closes and the K would open
resets back
what are the 2 Refectory Periods?
- Absolute Refectory period
2. Relative Refectory period
what is the Absolute Refectory period ?
happens negative til positive
Na channels in active new stimulation has no IMACT on the neuron
NO CHANGE
what is Relative Refectory period?
Neuron will respond to new but only very STRONG stimulation
