Exam 1 Flashcards
What is the neural net hypothesis?
the hypothesis that the nervous system is one large continuous tissue
Who came up with the neural net hypothesis?
Camillo Golgi
what is the cell hypothesis?
the hypothesis says that the nervous system consists of individual cells
Who came up with the cell hypothesis?
Santiago Ramon y Cajal
What is the neural doctrine?
the belief that neurons are cells that form the basic unit of the nervous system
Describe the main 4 components of the neuron anatomy
Soma (cell body)
Dendrites
Axon
Synaptic Terminal
Which of the two hypothesis is more widely accepted?
The cell hypothesis
What is the difference between an afferent and efferent axon?
an afferent axon is an axon that admits neurotransmitters, which are also sensory neurons
While an efferent axon is one that sends information OUT, also a motor neuron
What is an interneuron?
a type of neuron that connects the different brain regions between the CNS and PNS
What are the four types of neurons?
- anaxonic
- bipolar
- multipolar
- unipolar
What are the four types of glia?
- radial glia
- astrocytes
- microglia
- Schwann cells
What is the purpose of astrocytes?
Is it something that wraps around a synaptic terminal and helps with mechanical and metabolic support through scaffolding
What are Schwann cells?
it is something that wraps around the axon that allows damaged axons to regenerate in the PNS
What is the difference between diffusion and electrostatic?
diffusion is when ions want to be from a tightly compacted area, to a less compacted.
Electrostatic are the forces that make opposite ions attract each other or repel similar ions.
What is the resting membrane potential?
-70mV
Which ions are permeable and which are NOT?
- Potassium (K) and Chlorine (Cl) are moderately permeable.
- Sodium (Na) is NOT permeable
How many ions are in/out in the Na+/K+ pump?
3 Sodium ions are in, while 2 potassium are out
When is an absolute refractory period?
It is the period where there is hyperpolarization to take the energy back to its resting potential. In this process, another action potential cannot be refired no matter the strength until the cell is back on the resting phase
What is the relative refractory period?
The period right before an action potential where the cell is still relatively, negatively charged
What does myelin do?
helps propagate an action potential
What could happen if a neuron doesn’t have myelin?
action potentials can be slower
What are the five steps of the chemical synapses?
- synthesis
- packaging
- release
- receptor activation
- Inactivation
What is the difference between classical and peptide neurotransmitters?
classical NT are synthesized in the terminal button, while peptide NT are synthesized in the soma
Which part of the cell helps with packaging neurotransmitters
the golgi apparatus
What are IPSPs and EPSPs?
IPSPs decrease the likelihood of an action potential, while EPSPs increase that likelihood
