Chapter 2 Modules Flashcards
(36 cards)
What is monism
The idea that mind is made of the same substance as the rest of the universe
Ontogenetic explanation
How behavior develops
Functional explanation
Why a structure or behavior has evolved
Physiological explanation
Relates behavior to the activity of the brain. Machinery
Evolutionary explanation
Reconstruct the evolutionary history of a structure between related species
Example of evolutionary explanation
Human have a tiny tailbone because our ancient ancestors had a tail
What are widely branching structures of a neuron called
Dendrites
Long thin structure that carries info to another cell
Axon
By surrounding a connection between neurons it shields from chemicals , helps synchronize enabling axons to send messages in waves
Wrap around synapses
Astrocytes
Micro glia
Immune system removing viruses and fungi from brain
Oligodendrocytes ( in brain and spinal) and Schwann cells ( in periphery) do what ?
Build myelin sheaths , supply axon with nutrients
Radial glia
Guide migration of neurons axons and dendrites during embryonic development
Molecules that dissolve in fats cross blood brain barrier as well as
Vitamin A, D, iron, glucose( main fuel) , amino acids, purines, choline
Polarization
Difference in electrical charge between inside and outside cell
Inside negative
Difference is it’s resting potential
Sodium potassium pump
A protein complex transports three sodium ions out of cell while drawing two potassium ions into it
Sodium ions are more concentrated outside of cell and potassium more saturated inside
When neuron is at rest two forces act on sodium ..
Tending to push it into the cell
Potassium is positive charged and more concentrated inside cell. When the membrane is at rest ..
Concentration gradient drives potassium out of cell, the electrical draws then into cell
Hyper-polarization
Increased polarization ( difference in charges in and out of cell)
When membrane is at rest what drives potassium out of the cell .. what draws them in
Concentration gradient pushes out
Electrical gradient draws in
SP pump draws in
What is difference in hyper-polarization and depolarization
Hyper is exaggeration of the usual negative charge in the cell to a more negative level
Depolar is decrease in the negative within cell
If meets threshold the cell produces action potential
All or none law
The size and shape of action potential are independent of the intensity of the stimulus. Same amplitude and velocity . It doesn’t apply to dendrites because they don’t have action potentials
During action potential do sodium move into or out of it Why ?
During action potential, sodium move into cell . Sodium attracted by concentration and electrical gradient
After action Potassium moves out
Refractory period
Resist the production of action potentials
Absolute- membrane can’t produce
Relative- stronger than usual stimlus is necessary
Local neurons
Exchange info with close neighbors