Resting Potential Lab Report

The resting potential is generated by the specific changes in membrane permeability for of potassium (K+) and sodium (Na+) ions, which in turn result from concentrated changes in functional activity of ion channels. Cell membranes are made up of a phospholipid bilayer- consisting of two layers of linked fatty molecule. Various specialized proteins, such as ion channels, float in this bilayer. Ion channel are membrane-spanning proteins that allows the passage of certain ions through the membrane. The cell membrane of a neuron is selectively permeable to potassium ions, meaning that ion channels that will only allow potassium ions to exit or enter the cell freely. It is this selective permeability of the membrane to potassium ions that helps

Diffusion is the force that causes molecules of a substance to diffuse from of high concentration to regions of low concentration. If the concentration of potassium ions is unequal across the cell membrane, potassium ions will diffuse through the selectively permeable membrane until they are equally concentrated on both sides.

Diffusion results from the concentration gradient generated by the sodium-potassium pump. This mechanism, powered by ATP, pumps three sodium ions out of the cell for every two potassium ions pumped into the cell, causing a build up of potassium ions inside the cell. Potassium ions diffuse out the cell due to the concentration gradient, creating a potential difference across the membrane. Other ions, such as sodium, are unable to cross the membrane and thus remain concentrated on one side.

Consequently, the increased negative charge created inside the cell attracts potassium ions back across the membrane into the cell. This force is called electrostatic pressure. When the potential difference across the membrane is around -70mV, the electrical gradient exactly balances the chemical gradient and equilibrium is reached. There is no net movement of potassium ions and hence a steady state exists. Resting potential has been

A typical neuron has several thousand synapses. Chemical synapses connect axons of the presynaptic membrane to dendrites of the postsynaptic membrane, separated by the synaptic cleft. The presynaptic membrane is a specialized area within the axon that contains neurotransmitters enclosed in synaptic vesicles. There are many different types of neurotransmitters; they can be excitatory or inhibitory. Dopamine, GABA and Serotonin are examples of inhibitory neurotransmitters, while Acetylcholine and Glutamate are commonly excitatory