Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Module 3 Part 1
Module 3
| Term | Definition |
|---|---|
| anatomy | The study of body structure (deals with physical form) |
| physiology | The study of body function (the way processes occur) |
| sensory neurons | receive info from an organism's external and internal environment & transmit to brain (receptor → CNS) |
| interneurons OR relay neurons | connecting neurons that are usually part of a circuit; integrate information so that a response can occur (CNS → CNS) |
| motor neurons | transmit messages from the brain to muscle fibers or glands to elicit a desired response (CNS → effector) |
| cell body of a neuron | contains nucleus and organelles |
| dendrites | branched extensions of a nerve cell body |
| Dendrites & Cell body | responsible for receiving signals from other neurons |
| axon hillock | the region of the cell body that meets the axon; where signals, like action potentials, are generated |
| axon | projection of soma towards some other cell that serves to transport action potentials |
| synaptic terminals | branches at end of axon form synapses with the next neuron or target tissue; contain neurotransmitters |
| polarization | the state in which there is a difference in charge or voltage across the membrane (inside neuron = negative and outside neuron = positive) |
| potentials | changes in membrane voltage |
| resting membrane potential | voltage measured inside a neuron when it is not active (usually -70mV) |
| action potential | transmits information about stimuli along the entire length of an axon |
| gated ion channels | closed ion channels in the cell membrane that require a specific type of stimuli to open to allow ion flow (can require ligand binding or specific voltage to open) |
| hyperpolarization | a shift in membrane potential that makes the internal cell environment more negative (caused by positive ions leaving the cell) |
| depolarization | a shift in membrane potential that makes the internal cell environment more positive; if large enough, generates action potential |
| neuron depolarization process (AP generation) | voltage-gated Na+ channels open, Na+ floods cell, membrane potential reaches +62mV and generates an action potential |
| graded potentials | small changes in membrane potential that by themselves are insufficient to trigger an action potential; proportional to the magnitude of the stimulus (can occur in + or - direction) |
| graded hyperpolarization | stimulus increases K+ flow out of the cell, causing a shift toward a more negative state |
| graded depolarization | each stimulus increases the flow of Na+ into the cell, causing a shift toward a more positive state |
| threshold | the point at which the electrical potential has shifted enough in the positive direction to cause the opening of voltage-gated sodium channels |
| rising phase of action potential | as voltage-gated Na+ channels open, Na+ ions flow into the cell and cause an even greater shift in the positive charge of the membrane |
| all-or-none response | action potentials fire at full strength or not at all |
| falling phase of action potential OR repolarization | occurs as voltage-gated Na+ channels close and inactivate (can no longer be opened at threshold). Inactivation lasts a brief time, then channels reset. |
Created by:
sayeghs18
Popular Biology sets