Posted by I made a TikTok to demonstrate how neurons carry a charge and release neurotransmitters. In this video, dopamine is being released.
I made a TikTok to demonstrate how neurons carry a charge and release neurotransmitters. In this video, dopamine is being released.
For Carol’s STEAM project, she did a video that acts as a visual representation of the 4 steps in an action potential. For step one, the resting state, in which only the leakage channels for na+ and k+ are open. Once Carol ate the noodles, dopamine binds to the ligand-gated sodium channels. Due to this, na+ channels open and Na+ rushes into the membrane. This causes the membrane potential to increase and depolarize. Once it hits the threshold of -55mv, more na+ gates are open and the influx of na+ is a positive feedback loop. Once 30mv is reached, the na+ channels are inactivated and the k+ channels open. This causes the action potential to repolarize as the membrane potential begins to decrease. The membrane then becomes hyperpolarized as the membrane potential dips below -70mv, the na+ reset and some of the k+ channels remain open.
Meanwhile, the na+ then propagates down the axon and the action potential reaches the axon terminal. As a side note, the speed in which the na+ propagates down the axon is dependent on the myelinated axon. Myelin is wrapped around the axon and helps to increase the efficiency of the transmission of the action potential. A myelinated axon with a larger diameter allows for the action potential to be transmitted at a greater velocity as well as transports na+ more efficiently. Once the na+ reaches the axon terminal, neurotransmitters are released and ca2+ channels are opened. The influx of ca2+ in the axon terminal causes the neurotransmitter to be released into the synaptic cleft.