Neurobiology Exam 2 With Diagrams - 2021 / 2022 | 100% Correct

Neurobiology Exam 2 With Diagrams 2021 / 2022 Properties of channels gated - transition from open to closed states by changing their 3D configuration.; selective - Only certain ions permitted to pass. Selectivity arises from: • chemical properties (mainly charge state and distribution) of amino acid sequences lining the pore. • diameter of the pore when open. Passive - movement through open channels does not directly expend energy.; Channel Types Ion channels can be gated open in a number of ways: Random: open or close randomly, leakage channels Voltage gated: open or close depending on membrane voltage. Chemical/ligand gated: open or close by binding with a "ligand" often referred to as a "messenger" (extracellular messenger: "neurotransmitter"; intracellular messenger: "second messenger") Chemical AND voltage-gated: opened by binding transmitter only when membrane voltage is favorable Mechanical-gated ("stretch" channels): opened by membrane deformation. For each of the ions below, identify whether each elemental ion is at a higher concentration inside or outside of the cell. a. Sodium b. Calcium c. Potassium d. Chlorine a - outside b - outside c - inside d - outside