Biopsychology Flashcards
What are the major divisions of the nervous system? What are the other divisions of the nervous system?
- Central NS: brain and spinal cord
- Peripheral NS: everything else, connects CNS to organs, limbs, skin
- Autonomic NS
- –Sympathetic NS: uses energy, fight or flight
- –Parasympathetic NS: conserves energy, “rest and digest”
- Somatic NS
- –motor neurons
- –sensory neurons
What are the 2 major types of cells in the nervous system?
Glial cells and Oligodendrocytes (CNS)/Schwann cells (PNS): insulate axons with myelin
What are the functions of these glial cells in the nervous system?
a. physical support
b. myelination
c. clean up
d. guidance and direction
e. regulation
f. blood brain barrier: protects the brain from blood vessels with holes b/c blood is toxic to neurons
g. nourishment
(all for neurons)
3 general types of neurons
Sensory, motor, interneurons
Axon
sends info away from cell body, one per cell, can be myelinated
Dendrite
receives information, non-myelinated, many per cell
Synapse
gap separating transmitting and receiving neurons
Cell body
neuron’s core, holds genetic material, provides energy
Myelin
coats axons to form a sheath, helps neurons travel faster
Axon terminals
neurons stay trapped here until action potential releases them
Nodes of Ranvier
gaps b/w myelin to increase transmission speed
Action potential
when depolarization reaches the threshold of excitation, the action potential travels down the axon to its terminals and releases the neurotransmitters to send a message to a nearby neuron
What is the “all or nothing” rule?
an action potential is either fired or its not, AKA the threshold of excitation is either met or its not
What is a ligand?
A substance that binds to receptors
What are neurotransmitters and what do they do?
They are mainly hormones that are triggered and released throughout the body, their purpose is to allow communication b/w neurons
