Muscles, Part 1 - Muscle Cells: Crash Course Anatomy & Physiology #21
Video Overview & Insights
We're kicking off our exploration of muscles with a look at the complex and important relationship between actin and myosin. Your smooth, cardiac, and skeletal muscles create movement by contracting and releasing in a process called the sliding filament model. Your skeletal muscles are constructed like a rope made of bundles of protein fibers, and the smallest strands are your actin and myosin myofilaments. It's their use of calcium and ATP that causes the binding and unbinding that makes sarcomeres contract and relax.
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I’m a huge fan of your content! Your explanations are incredibly clear. Would you consider doing a deep dive into the mechanisms behind vasodilation and vasoconstriction? I’d love to see how you visualize those processes! Love form Poland!!!
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Chapters:
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Introduction: Muscle Love 00:00
Smooth, Cardiac, and Skeletal Muscle Tissues 1:18
Thank you to Hank and the team for saving my butt for over a decade. Here in 2026 and beyond lol
Structure of Skeletal Muscles 2:40
Protein Rules 3:25
The body is amazing
Sarcomeres Are Made of Myofilaments: Actin & Myosin 3:54
Sliding Filament Model of Muscle Contraction 4:38
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Review 9:17
Credits 9:57
This is very good, thanks!!
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how did this guy make muscle cells actually cool
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Watched crash course videos preparing to get into med school, and now I'm watching it again to get a refresher for my licensure exam. Haha
@dabiwabichanAnyone else here in 2025?
@codybelle77Me struggling through A&P…. Me reading the 30 pages about bones in my A&P book….. me being even more confused… me watching these videos again….. me understanding the chapter better via this sub 10 minute video….. me passing quiz…. Me happy
@apcsoxI have a test today I didn’t study for bc I had another test that I needed to prioritize and this channel is saving my butt. THANK YOU
@maddiecapuano67Wow! This was great!
@yosoyaltafrecuenciaI was not ready for that Fault in Our Stars reference
@ItIsBeyondDisbeLEAFi can't believe that i actually finish this video, but it was so interesting that i may watch it again. thank you!
@erickrivera5740I’m so confused what movement does the entire muscle is being used in isometrics so why do you need movement.
@cata9223been watching since middle school, now I'm in veterinary school still watching these the night before my exams lol
@mildredmullings2801never stop please
@ethanhellerman65This is amazing!!!! ❤❤
@notesdecoeurVery helpful. Thank you.
@christyharris4382First
@ucyclHank how did you know that I was simultaneously eating, texting, AND taking notes im scared
@aubreyburnham1399Thank you !!!
@francesparker4371I understood a whole week of my college physiology class in this video
@anna20812Very well explained ❤ thank you
@marinomusico5768YOU'RE A GANGSTER
@kotamochizuki9927I love how you explain, thank you .
@johunna2991😂that was great!❤
@afshinzaim8956You speak too fast..slow down
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I love you
@kimjulie8862she sounds like the guy from south park 😂
@SageModeObito242Why you don't have muscles😮😮
@rajking1644you should make a tv show about actin and myosin it would be so good.
@sophiaschreiner9854more than great
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@zuhaibsadiq4542Thank you Hank
Coming back to this video after years
I dropped out of school due to depression, but i could never get back to studying Academically
But all Crash course videos, have been the main source of knowledge.
But you also ruined me, due to these kind of videos, i expect my learned educated Friends / peers to know as basics.
Unfraternally they only learnt their subject and nothing else
But
Thank you
Do U have video like this about body fat and visceral fat ?
@hjcmalaysia1013love the "okay, okay" fault in our stars reference
@ashahasnain6546The okay, okay reference was beautiful
@morganfischer8241One video on smooth muscles and latch mechanism plz
@lahore4222better love story than Twilight.
@travisbickle3835I’m here studying for STEP 1 and I forgot how much I loved you during MCAT studying!! Truly the GOAT
@giannaj9397you talk so fast that I had to put it on 0.5 speed 😂
@dragana8281If he was my actual professor, I wud be do attentive during classes bc of the way he talks. Its like 1 second of pacing out and uve missed a whole paragraph
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