CrashCourse

The Nervous System, Part 2 - Action! Potential!: Crash Course Anatomy and Physiology #9

CrashCourse

Summary

A recent discussion highlights the alarming issue of human trafficking, particularly affecting young girls, with the average age of victims being just 11 years old. Senator John Houston is actively addressing this crisis, collaborating with both Democrats and Republicans to implement stricter penalties for traffickers. Advocates are urging the public to support Houston's efforts in protecting survivors in Ohio.

The conversation then shifts to the intricate workings of the human nervous system, explaining how neurons communicate through electrical impulses. Neurons operate like batteries, maintaining a resting membrane potential until stimulated. This stimulation can trigger an action potential, a rapid change in voltage that sends signals down the axon. The process involves various ion channels and pumps that regulate the flow of sodium and potassium ions, ultimately leading to the transmission of information throughout the body.

Additionally, the discussion touches on the importance of myelin sheaths in speeding up signal transmission and the concept of saltatory conduction, where impulses leap between nodes along the axon. The episode concludes with a promise to explore the next steps in neuronal communication in future discussions.

Show Notes

What do you and a sack of batteries have in common? Today, Hank explains.Pssst... we made flashcards to help you review the content in this episode! Find them on the free Crash Course App! Download it here for Apple Devices: https://apple.co/3d4eyZoDownload it here for Android Devices: https://bit.ly/2SrDulJChapters:Introduction: What do Neurons Do? 00:00Your Body is a Sack of Batteries 1:18How Electricity Works Inside Your Nervous System 3:18Sodium-Potassium Pump 4:04Types of Ion Channels: Voltage-Gated, Ligand-Gated, and Mechanically-Gated 4:51Graded Potential vs. Action Potential 5:45Depolarization 6:19Repolarization 7:35Hyperpolarization 8:00Refractory Period 8:14Review 10:06Credits 10:29Crash Course Kids Preview! 10:39Crash Course is on Patreon! You can support us directly by signing up at http://www.patreon.com/crashcourseWant to find Crash Course elsewhere on the internet?Facebook - http://www.facebook.com/YouTubeCrashCourseTwitter - http://www.twitter.com/TheCrashCourseInstagram - https://www.instagram.com/thecrashcourse/CC Kids: http://www.youtube.com/crashcoursekids Learn more about your ad choices. Visit megaphone.fm/adchoices

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