Week 5 Flashcards
What is a neuron?
Neurons are the basic cellular units of the nervous system and are basically electrochemical information storage and transmission devices.
What are the types of neurons?
Unipolar, bipolar and multipolar
Unipolar- Relay information forward; 1 axon and no dendrites
Bipolar- Sensory perceptions; 1 axon and 1 dendrite
Multipolar-
Communicate with other neurons; 1 axon and many dendrites
What is the function of the glial cells?
Glial cells help with the ‘menial’ tasks of cleaning up waste products, providing nutrients and physical support, and guiding developing neurons to their proper places.
What are the parts of neurons?
Dendrites (receive information), cell body or soma (process information and contains the nucleus) and the axon/terminal button (sends information)
Describe the process of dendrites
Dendrites maximize branching out to receive input: chemical signals enter the dendrites spines, then travel down to the cell body where they are averaged to one of two simple conclusions- fire an action potential or don’t fire an action potential.
What happens when the signal of dendrites is fire?
If the signal is fired, then that signal runs down the axon- all or nothing signal.
Dendrites
receivers
Axon terminals
transmitters
Schwann’s cells
type of glial cell (they make the myelin)
Axon
The conducting fiber
Myelin sheath
insulating fatty layer that speeds transmission
Sensory neuron
activated by information inputted from the environment
Motor neuron
transmit impulses from the spinal cord to the skeletal and smooth muscles
Interneuron
allows for sensory neurons and motor neurons to communicate with the CNS (central nervous system)
Neurotransmitter
is triggered at the end of the axon that travels across the synapses.
What are the principles that help drive the action potential?
Electrical gradient (difference in charge) and a concentration gradient (difference in concentration)
Anions
negatively charged ions
Cations
positively charged ions
Electrostatic pressure
The repelling force of 2 ions or attractive force
Diffusion
movement of molecules from high concentration to low concentration