Structure & function of skeletal MUSCLES: Myofibrils, sarcomere, sliding filament theory.

Learn the structure of a myofibril and sarcomere, including the different bands and zones (I,A H and Z) and how these change when a muscle contracts.
I describe the sliding filament theory and go through the differences between slow and fast-twitch muscles.

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2)FULL A-LEVEL ACTIVE RECALL WORKBOOK

3) A-LEVEL NOTES

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@letscreatesomething

[Lorenzo-nfdk]

imagine they just made all this shit up

[bowww]

first year medicine student coming back to your videos to revise my first semester since the level of detail is still so helpful and relevant thankyou miss estruch i'm your biggest fan fr

[ajtv]

Muscles was the reason I got a C last year, only topic I left out and it was all over the paper3, learning it this time around lol, thank you

[triciahardman]

Thank you SO much for all of your fabulous videos. I use them in my tutoring, especially when I'm teaching online.

[Jonboyr]

Thank you, thank you, thank you as well. I've watched so many videos and couldn't find any info on the ATPase that you went into. That connected a lot of dots for me. Also, this is the best presentation of the power stroke as well as the picture at the end of the the bands and zones.

Thanks so much for this video!

[sakeenarajpal]

Thank you, thank you, thank you!! Your videos are amazing and have been such a help!

[uig]

Hi, I’m a bit confused as to why fast twitch fibres have a higher glycogen storage? What does this do, can you please explain ! X 18:14

[AG-qlsy]

Up to now I’ve understood everything for topic 6 but this started to confuse me... the whole ATP and ADP thing was confusing

[Chrissy]

Great video, thanks for uploading! I understood the vast majority of the material covered in this video. One detail that is kind of unclear to me is why there is a high glycogen store specifically in fast twitch muscles? I understand that the glycogen will be converted into glucose and then converted into ATP but since both aerobic and anaerobic respiration will require ATP shouldn't there be a high concentration of glycogen in both types of muscle?

[adhamahmed]

Is the myofibrils one large strand of cell or is the Myofibrils made up of lots of small muscle cells which are collectively called a myofibril?

[juliaonyebuchi]

Is it correct to say just the I and A band as I got taught they were called the isotropic band and the anisotropic band, but is saying it short hand (I &A) fine in the AQA bio exams?

[uwotm]

Hi miss, why do fast twitch fibres fatigue more quickly? Thank youuuu

[olpp]

Hey, the CGP guide says that ATP is used to move the myosin head, causing contraction. Why is this different? Thank you so much :)

[sabaaalkadi]

How does the H zone which is only myosin shortens, and then the A band which is myosin length and actin stays the same?

[bellastarmartin]

Hi Miss,
Good evening.
Is everything on your PowerPoint slides all that I need to know for this lesson?

I have a topic test tomorrow and my teacher was not in on Monday so I haven't been able to learn anything about Muscles(only see on once on Monday and once on Thursday for this week).So I'm trying my best to finish making these notes then revising.

[fatima-degv]

hiii this video helped loads, one question, u said that the sliding filament theory stops when the actin cannot move closer together, what does this mean, move together how?