PSY 1001 Lecture Notes - Resting Potential, Neurotransmitter, Tetrodotoxin
Document Summary
B. i. ii. i. ii. iii. iv. v. vi. i. ii. ii. i. ii. iii. ii. ii. iii. i. ii. i. Emerged from general cell theory in late 19th c. Nervous system (ns) made up of 2 kinds of cells: So perhaps 100 trillion connections in the brain. Electrical signals in the neuron are generated chemically. Ion gradients are maintained across the cell membrane. The electrical potential generated by these gradients amounts to about 70 mv or . 07 volts. In other words, just 15 neurons wired in series produces 1 volt. Normal functions neuron critically depend on these ion gradients. The cell membrane is formed from two layers of lipid molecules. Proteins serve as ion channels, receptor molecules, and other functions in the membrane. Two kinds of ion channels: open and gated. Gated channels act as though there were a door or gate. If neuron stimulated above threashold (-50 mv) then triggers action.
