Join Leslie as he shares this last video on muscle contraction explaining with full clarity the smallest details on how this works.
Enjoy!
Transcript of Today’s Episode
Hello and welcome to another episode of Interactive Biology TV where we’re making Biology fun! My name is Leslie Samuel and in this episode, Episode 43, I am going to go into the details of muscle contraction. This is going to be the last video in the muscle contraction series, so, enjoy! Let’s get right into it.
You can always go back to Episode 42 to refresh your memory but, we said that the functional unit of contraction is called the sarcomere and, that is what we’re looking at right now. This unit is one sarcomere. We said that we have a thick filament that is called myosin and, we have a thin filament that is called actin. We said that, when muscle contraction happens, the more the neuron releases neurotransmitter that stimulates calcium release. When that happens, the fibers slide against each other just like this. So, as the muscle fibers becomes shorter, that is the muscle contracting. And you can clearly see that in this animation.
The reason we said that this can happen is because on the myosin filaments, we have these heads and those heads extend and bind to the actin. When they bind, they kind of flex so, it moves in this direction and that pulls the actin shortening the sarcomere.
What we are going to do today is we’re going to look at the details of what is happening there. We are going to look at six steps in muscle contraction. This is another image that’s showing something similar to what we’ve looked at. We have the myosin heads. Let me do that in a different color so that you can make sure to see it because we have a lot of red there. We have the myosin heads that are binding to the actin filaments.
Here, we are going to be looking at that in more details. We have the actin. Yes, it’s a different spelling because it’s from a different language but, on the actin filaments, there are two things that are very important. We have tropomyosin as you see here so that’s this long strand here. On top of the tropomyosin, we have troponin. This is a complex that we find all along the actin filaments.
Here’s the situation. Because this is here, the myosin heads want to bind to the actin. There’s some binding sites on the actin so, let’s say this is a binding site right here. But, what’s the problem? The tropomyosin is covering that binding site so, the myosin heads cannot bind. Okay, so, we have these myosin head-binding sites all along the actin; myosin heads want to bind, we have all these myosin heads ready to do their business but, they cannot because it’s blocked by the tropomyosin.
All right so, let’s go now and look at the six steps of muscle contraction. Step number one. Calcium is released from the terminal cisternae. Remember we said that the terminal cisternae is a part of the sarcoplasmic reticulum and that is where calcium is stored. So, calcium is released. You can see here, we have this little binding site for the calcium so the calcium now comes and binds the troponin. So, here we have calcium and binding to the troponin. And then, what that does is it causes a conformational change. To put it more simply, we’re just moving the tropomyosin-troponin complex. So, that moves and, when that moves, it exposes the binding sites on the actin. That’s step number one. So, step number one: We had calcium in the terminal cisternae that is released when there’s a stimulus. The calcium ions bind to the troponin causing a conformational change in the troponin-tropomyosin complex. In other words, it’s moving out of the way. And then, the next step can happen. That step is, the myosin heads can bind to the binding sites on the actin. So, this is the one binding site. For simplification we’re just showing one myosin head but, as you know we have many myosin heads all along this actin.
In order for that to happen, we said that there’s normally ATP that’s on the myosin heads and you saw that, you saw that in the previous figure. But, that ATP has to be hydrolyzed to become ADP and an inorganic phosphate (Pi). So, we have ADP and the phosphate. All right, so, we have the myosin head that has bound to the binding site on the actin. That was step number two. Step number three. This ADP and Pi is released from the myosin head. I’m not showing that in the figure but, just imagine that being released. When that is released it causes the power stroke. In other words, it causes this guy here to flex. And when it flexes, it moves in this direction and that causes the actin to slide across the myosin.
Okay, so, calcium is released, step number one, binds to the troponin, causes this change in the troponin-tropomyosin complex so that it gets out of the way; ATP being hydrolyzed into ADP and inorganic phosphate is a state that this needs to be in for the myosin head to bind. When those are released, the myosin head flexes and we get the power stroke. That’s step number three.
Let’s go to step number four. Step number four is another one that I’m not showing but, we have ATP. So, this is an ATP molecule that comes in and binds to the myosin head. When that binds to the myosin head, the myosin head then detaches from the actin so, we no longer have that connection. That’s step number four.
Step number five. ATP is hydrolyzed which re-energizes the myosin head. So, once we have ATP being hydrolyzed like it is here, that re-energizes the myosin head and it’s ready to go again.
One more step, step number six. This calcium here needs to be gone. So, we have the terminal cisternae and it’s not shown here. So, I’m just going to draw it with my great artistic skills. We have calcium pumps in the terminal cisternae. What that does is it basically pumps that calcium back in. So, we have calcium being pumped back in that is going to cause the troponin-tropomyosin complex to go back to where it was and it’s going to be blocking… I should have done that in green to keep the consistency. Oh, I still can, why not. Okay, so we have the troponin-tropomyosin complex that is blocking once again the binding site for the myosin head.
All right, so let’s recap on that real quick. Step number one: Calcium is released, binds to the troponin. When it binds, it causes a conformational change or a shift, whichever one you want to call it, it causes that shift exposing the binding sites on the actin. Step number two: Myosin head binds to the actin. Remember that the ATP has to be hydrolyzed into ADP and Pi in order for that to take place, it has to be re-energized. It gets that from that hydrolysis process. Step number three: ADP and Pi release that causes power strokes that causes this guy to flex. Then, ATP comes in, binds to the myosin head, causes the myosin head to be released from the actin. The myosin head gets re-energized when the ATP is hydrolyzed back into ADP and Pi. Calcium ions are pumped back into the terminal cisternae and this process can happen again.
Well, that’s pretty much it. That is muscle contraction. If you have any questions, go ahead and leave them in the comments. That’s all for this video, and I’ll see you on the next one.
This video is “Fabulous”.
I’m a Univ. student in korea, and my proffesor can never make me and my friends understand.
but this 10 mins video makes me understand!!!!
You r the best
——a Student who loves Biology
That’s awesome. Glad you are enjoying the content and glad it is helping you to understand. Make sure to share it with all your classmates 🙂
Just Testing!
Dear Leslie, I am 44 years old and going back to school to become a Nurse. I have to upgrade my Biology. I have been struggling with studying. I stumbled onto one of your videos on You Tube when I was searching for information on Na+/K+pump. I found myself on your site watching many of your lectures. I would like to thank you for making it fun, interesting, and easy to understand. I have learned so much from just watching and listening to you.
Deepest Thanks, Sincerely, Tara
Hi Tara,
You are very much welcome. I’m soooo glad that you have found the videos to be helpful, and fun. That’s my goal. I know that it can be complicated studying from the textbook, so I want to do whatever I can to help. You can help me by sharing it with your classmates, and even professors.
All the best with your program, and check back often because we’ll be doing some awesome stuff in the near future 🙂
Leslie
Hi, I’m from Italy, I am studying physiology and your videos are helping me so much. Thanking you is just not enough! You are really skilled in teaching.
Hope I didn’t make bad grammar mistakes!
That’s great. Glad to know that you received a lot of value in the videos. Don’t worry about grammar – I make mistakes with that all the time 🙂
It would be useful if there was something describing the difference between fast twitch and slow twitch fibres in terms of structure ect.
But very well explained!
That’s a good topic to cover in a video when I come back to the muscular system. Here’s a good introductory article on Fast and Twitch Muscle fibers. Hope that helps. Otherwise, you can always do a google search on the topic.
Thank you. It would be great if you could cover that in a video.
I love this video by the way!
Thank you for your feedback Imran. Glad to know that you love the video. Those comments motivate me to make more 😀
I was totally confused about this after my anatomy class…then I watched your video a couple of times and can not only understand what is happening but explain it to others…hope I do well on my exam tomorrow!! Thank you so much!
Vickey, that’s SO AWESOME. Glad to hear that. Every time I get a message like that it motivates me to do more. All the best on your exam tomorrow. Make sure to come back and let me know how it went.
Hi Leslie,
Please bear with me. I really like to understand how neuron cells send signals to different types of muscles. Lets say, there is an excess extracellular calcium, how is this going to affect the contraction of the skeletal muscle cell? How about the smooth muscles like the intestines? Does it have the same effect like in cardiac muscle cells?
Thanks a lot.
Not a problem. Feel free to ask your questions. I assume that the effect is the same. However, I haven’t studied that in depth so I cannot guarantee that it’s definitely that way. You’d have to do more research on the subject.
great video. thanks. tell me during a muscle ATP converts to ADP only once or many times? I actually need to watch your vid about ATP and ADP. need to know what happens there and how they brake done and build up. Is awesome and your voice and your english is excellent and clear.
Hello Leslie, I have some questions, what happens when a muscle get tired?
Why does i hurt when you over excersize.
How does “lactic acid” fit in to the picture.
You do a great job in explaning how a human works, i never learned so much in so short amount of time. Bas.
Hi Bas,
Glad to know you are learning so much. To answer your questions . . .
Muscles get tired because they run out of the stuff they need (ATP, O2)
It hurts because your muscle fibers actually tear. They tear and are rebuilt bigger and stronger over time.
Lactic acid is produced during anaerobic respiration as a byproduct. That also causes some of the burning that you feel.
Hope that helps.
Hello, I forget to ask an other question.
What is the difference between a hart muscle (get never tired)
and a normal muscle?
Bas.
Different structure, doesn’t work as hard as when you are exercising hard. Your questions are too detailed to answer in a simple comment. Sorry that I can’t go into too much detail in the comments. Too much to do, too little time.
wow!! im obsessed with your videos!! u explain everything so well!!thank u!!!
@ey7681 That’s awesome. Glad to know you are getting value in the videos 😀
Awesome videos !!! One of the best videos I have ever seen.
@REA0321 Thank you very much! Stay tuned for more!
I can’t tell you how much you are helping me w/ my physiology class. My professor does not teach it well at all and doesn’t realize that he is ineffective. You make me feel like my goal is attainable. Don’t ever feel like you don’t make a difference…….
@ruddergrl1 Glad to be able to help. All the best in your class.
I LOVE YOUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUU MY HEROOO <3
@darktrool LOL. Thank ya 🙂
You sir…are my hero! 😀 <3
@MayokoLove Nahhh, lol. Glad it’s helping though!
You are incredible! Thank you so much…It makes so much sense…… I love you.
@369thegoose1 Awww, thanks for the feedback, and for the love 🙂
Stay tuned for many more!
Hi…may I ask a question ….. so is it true that the myosin myofilaments do not move and the actin myofilaments move by sliding on the myosin myofilaments? Thanks, I hope I hear from you real soon….
Thanks
🙂
Hi…may I ask a question ….. so is it true that the myosin myofilaments do not move and the actin myofilaments move by sliding on the myosin myofilaments? Thanks, I hope I hear from you real soon….
Thanks
🙂
@369thegoose1 All questions are answered in the Interactive Biology community forums from now on. Go to the website in the description and then visit the community. This is to make it as efficient as possible as we have multiple people over there to help answer questions.
All the best
All questions are answered in the Interactive Biology community forums from now on. Go to the website in the description and then visit the community. This is to make it as efficient as possible as we have multiple people over there to help answer questions.
All the best
you R the maaaaaan ! i swear U R greaaaaaat
you R the maaaaaan ! i swear U R greaaaaaat
@mo0odina Thank you! 🙂 Stay tuned for more Biology videos coming very soon!
Thank you! 🙂 Stay tuned for more Biology videos coming very soon!
gonna go kill an anatomy and physiology midterm because of this!
Thanks, subbed and am recommending to all my classmates
@anfro18 THANK YOU! We appreciate you spreading the news to everyone 🙂 Good luck with your midterms!
THANK YOU! We appreciate you spreading the news to everyone 🙂 Good luck with your midterms!
@InteractiveBiology This, quite literally, saved me on the midterm on 4 different questions.
Thanks yet again!
This, quite literally, saved me on the midterm on 4 different questions.
Thanks yet again!
@anfro18 Wow! That’s fantastic! 🙂 Stay tuned for more because we have a lot more coming 🙂
Wow! That’s fantastic! 🙂 Stay tuned for more because we have a lot more coming 🙂
You just saved my life. I was the only one in Anatomy who was totally confused. You are amazing. Thank you!!
@baby3194 YOu’re welcome! Keep on watching to learn more 🙂 Have fun with all our Biology videos!
YOu’re welcome! Keep on watching to learn more 🙂 Have fun with all our Biology videos!
i like your videos, can you nexplain it in german 😉
Thankyou, very helpful
thank you very much!
do you have lectures for a cardiac and smooth muscles?
I don’t know self how to thank you, coz these sequence of events of contractile process in skeletal muscle #excitation-contraction coupling of your’s helped me alot. Thanks very much!
My Allah bless you bro.
Thank you so much..its really fun to learn.
you are amazing .Thank you so much !!!
Leslie…you are gold!
I have just found your website and simply could not wait to tell my lecturers/student body about you!You have made my study a pleasure and I look forward to more of your work. From the bottom of my heart THANK-YOU!
From Australia with Gratitude!
Anne-Marie
Well thank you very much Anne-Marie,
I’m trying to do my best to provide the best resources I possibly can. Stay tuned for more, because I have lots coming!
dats really a very good explaination………I got everything very clear now…….thank you very much
dats really a very good explaination………I got everything very clear now…….thank you very much
dats really a very good explaination………I got everything very clear now…….thank you very much
What about the Mg++ that is responsible for the Ca++ to go back the Terminal Cisternae? Otherwise, this video is very very very helpful. Thanks
What about the Mg++ that is responsible for the Ca++ to go back the Terminal Cisternae? Otherwise, this video is very very very helpful. Thanks
Huge Fan!!! I’ve been using your videos to help me get through the start of my doctoral degree in Physical Therapy – MUCH THANKS!!!
Huge Fan!!! I’ve been using your videos to help me get through the start of my doctoral degree in Physical Therapy – MUCH THANKS!!!
when i first heard you say make biology fun i thought that this would be crap
but you really did make it fun and understandable
when i first heard you say make biology fun i thought that this would be crap
but you really did make it fun and understandable
I think my university may as well forward my tuition fees to you…please keep it up!
I think my university may as well forward my tuition fees to you…please keep it up!
Thanx a million!
If all uni doctors and professors would explain stuff like you do, I would have NEVER skipped a class!
Thanx a million!
If all uni doctors and professors would explain stuff like you do, I would have NEVER skipped a class!
Wow, that was the best!!! A++++++++++
Wow, that was the best!!! A++++++++++
thank you, was Magnesiun used to relax the muscle.
thank you, was Magnesiun used to relax the muscle.
thank you, was Magnesiun used to relax the muscle.
why is this so much different than my textbook? i dont know which to study, but yours is more clear and specific. thanks and nice job!
why is this so much different than my textbook? i dont know which to study, but yours is more clear and specific. thanks and nice job!
I love how you go over everything a few times to help learn it, and that it’s easy to understand. This has been great to help me learn and understand muscle contraction as in the lectures, they will only explain really once or twice and are sometimes more difficult to understand. Thanks a lot!
I love how you go over everything a few times to help learn it, and that it’s easy to understand. This has been great to help me learn and understand muscle contraction as in the lectures, they will only explain really once or twice and are sometimes more difficult to understand. Thanks a lot!
I wish you were my professor.. Some of these professors are just not good at teaching.
I wish you were my professor.. Some of these professors are just not good at teaching.
Very simple to understand thankyou!
Very simple to understand thankyou!
As a second year university student this video has really helped me, thanks a lot !
As a second year university student this video has really helped me, thanks a lot !
What’s the purpose of troponin causing a wall between myosin and actin.
What’s the purpose of troponin causing a wall between myosin and actin.
this was very diff topic i fully understand
this was very diff topic i fully understand
this was very diff topic i fully understand
by watching these videos
by watching these videos
so that your muscles don’t contract all the time?
so that your muscles don’t contract all the time?
Thanks.
Thanks.
Your videos are very helpful. Thank you for contributing such great videos. I am med student and there are some great points that I am picking up from your videos. Thank you.
Your videos are very helpful. Thank you for contributing such great videos. I am med student and there are some great points that I am picking up from your videos. Thank you.
I appreciate your videos verry much and iam really intereasted on them.Iam astudent iam studying pharmacy.ihope that you will make videos about renal physiology and endocrinology if you can .thankfuland iam soo
I appreciate your videos verry much and iam really intereasted on them.Iam astudent iam studying pharmacy.ihope that you will make videos about renal physiology and endocrinology if you can .thankfuland iam soo
What about the acetocholinase? that assists in the process of removing calcium and resituating the muscle fibrile in its relaxed state by eating up the inorganics leftover? I’m sure you know what I’m talking about. Or, by all means correct me if I am wrong. Great info though. You really can explain it in a way that fits A to B to C….etc. Thanks.
What about the acetocholinase? that assists in the process of removing calcium and resituating the muscle fibrile in its relaxed state by eating up the inorganics leftover? I’m sure you know what I’m talking about. Or, by all means correct me if I am wrong. Great info though. You really can explain it in a way that fits A to B to C….etc. Thanks.
acetylcholinesterase ….that is the correct spelling. DAMN this A&P crap is so TECHNICAL!!!
acetylcholinesterase ….that is the correct spelling. DAMN this A&P crap is so TECHNICAL!!!
i am having hard time in biochemistry also can u guys plz upload lecture on biochem??
i am having hard time in biochemistry also can u guys plz upload lecture on biochem??
ya he is life saver thank yu 🙂
ya he is life saver thank yu 🙂
Thanks for making “Muscle Contraction topic” interesting and more importantly understandable
Thankss ~~ !! :))
This was great – thank you!
Hi, have you wondered this method called the Max Muscle Method? (look for it on google). My sister says it gets people stronger.
Very good video.can you explain the increased cross myocyte diameter during contraction? thanks
keep uploading —for pathology ,pharmacology and microbiology !!!! will be of great help 😀
Reeally excellent video! Thank you, thank you very muchh!!
That was great! Thank you for such an awesome and easy to understand explanation:)
german image?
Thanks so much! Very helpful 🙂
thankyou so much!
Awesome!!
What program are you using for this video?
In 9 minutes you just did what my teacher was trying to do for over 3 months ! You explained the whole thing, and.. wouah !! I finally got it !! Thank youuuuuu
So much more clearer than bio 223 teacher. I actually understand it now.
Thank you so much!
I go to UCLA. Youtube has taught me most of what I need to know
do you have any videos on smooth muscle contraction? This one is on skeletal muscle but I need the one with MLCK and MLC and calmodulin
I enjoyed your video. My instructor provided our class with 12 steps and our textbook has different steps as well. Though, I am starting to understand it. I would like to email you the 12 steps instead of posting them on youtube. to confirm they are correct. Could you please provide an email. Thanks
YOU are a LIFESAVER. Thank you so much!!! My professor isn’t the most helpful!
The greatest video ever when it comes to mind numbing muscle contraction. It just proves the power of good teaching. There are no dumb students, there are teachers who unable to explain. Cheerrrrs! I am so happy now 🙂
These videos are life-saving. I’m a pharmacy intern but my mind is all blank when it comes to physiology, biology and anatomy. So, THANK YOU SO MUCH!
We need teachers like you Professor! THANK YOU and God bless!!!
Excellent!!! Thank you so much for the explanation!
This is such a helpful video! Very clear, concise explanation which brought these concepts to life for me. Thank you! Looking forward to watching more of your Biology videos. Feeling much more confident for my anatomy midterm coming up. 🙂
am here because of my STRUCTURE AND FUNCTION CLASS in COSTAATT….excellent video!
thank you so much your videos saved my life for this test!!
@wlzbaqs yes i mean it. before I started eating right it didn’t matter how much I exercised my abs were still jello. Listen to this The surprising part is my friend who is not doing much excercises, maintaining his six pack with this secret food items. you can watch out here –> bit.ly/Qk8H6D?=csepgi
I was hoping to hear more about the muscle contraction beginning from the axon terminal. With acetylcolene and sodium being released
Thank you for this video and for all of your videos! You always break it down in a way that makes it clear to me. I did extremely well on my test!
Best YOUTUBE video explaining the function and structural components of a sarcomere in a myofibril. WHOOP – WHOOP, I’M GOING TO PASS MY A&P TEST WITH AN A+!!!! LOL
THHHHHHANK you…Helped soooo much.
Thank you. Bless your heart sir.
wow this video really helped… thank you so much…
I have read this section again, and again in my text. Until I saw your video, it didn’t make a much sense. Now it’s much more understandable. Thanks!
Thanks great video!!!!
Thank you so much, God bless you.
why should ATP be hydrolysed during d second step
I think it’s cos it gives it energy to move the myosin head but to keep to doing it needs more ATP?
The hydrolysis of ATP gives energy so that the myosin head can bind
Hi,
Thank you for your videos!
I just have a question : How does Ca travel from the SR to the Troponin?
A second year university physiology course I am in says ADP is released at the end of the power stroke?
Just make sure you are not confusing the action of the power stroke occurring in real time or if he is referring to when the action of power stroking is over
Greetings,
My name is Fransuas and I am a medical student about to take USMLE step 1. First I would like to congratulate you on your great videos. You teach in an excellent way I wish my professors in collage would have teach like that and now I wouldn’t have doubts on the more complicated mechanisms. I use your videos when I have doubt or to refresh my memory. I wanted to ask you if you have a smooth muscle contraction video?(con. on next post)
I just saw the skeletal muscle contraction video and is excellent. As you know the smooth muscle is different with the Ca- calmodulin and other things that I get mixed all the time. If you have it can you send me the link? Because I can’t find it. Thank you very much I really appreciate it.
Fransuas
PS.
Just in case I wrote to the email on the website also.
In one muscle contraction only one ATP will be used… !
i seriously love you… thank you so much for this amazing video…. our teacher didn’t even teach us this and our exam is gonna cover this as well. so i thought i was pretty much screwed. but you literally saved my life….!!! again, thank you so much for uploading such an awesome video 🙂
Evolution is just amazing, at this level you realize how everything is chemistry in action.
What role does Mg ion play in the relaxing of muscles??
I saw the notation for it in one of the pictures, but it wasn’t mentioned. I love your videos! I didn’t understand this by just reading my anatomy book- very helpful!!!
VERY NICE SIR,THANK FOR U R WONDERFUL PRESENTATION
our country needs to invest in these kinds of videos that help students learn and understand concepts
if I had money i’d donate.
Brilliant.
@unkiazs sure is right. before I started eating right it didn’t matter how much I exercised my abs were still jello. Listen In a best female model 2012 exclusive interview she had mentioned about her strong abs with this 7 food items. have a look here -> bit.ly/XE2Be0?=txhlbb
Wassup. Exceptional clip. My school friend’s muscles grew extremely fast as though he was injecting anabolic steroids. Found out this man wasn’t. I’ve consistently fought to put on muscle tissue. My friend tried the Muscle Building Bible (google it) I’m going to take a crack at it.
Awesome video!
awesome great explaination
anybody else hear the pope from bob and tom?
Wow. Amazing
AMAZING!!!!!!!!!!!!!!!!
Excellent explanation!! I’m British and your accent makes everything so much more interesting!!!
It was actually fun! Thank you very much!
This is so much easier to understand than a book. Thanks
Surely JESUS CHRIST IS OUR GOD ! Through HIM all things were made; without Him nothing was made that has been made – GET SAVED NOW – JESUS CHRIST SAVES
OMG! Thank you soooo much for explaining this! My instructor made this process hard to comprehend. Learning it from a book on your own is so one-dimensional. Thank you for explaining this so I could understand it! I will be visiting the interactive site as well.
OMG! Thank you soooo much for explaining this! My instructor made this process hard to comprehend. Learning it from a book on your own is so one-dimensional. Thank you for explaining this so I could understand it! I will be visiting the interactive site as well.
You’re awesome!! Thank you for making these helpful videos!
Thank you very much for making this video……it truly helps me….
Thanks this helped me understand a little more
where does the magnesium come from and what does it do
That was totally helpful, I finally get it. Thank you.
Have you tried Morsch Muscle Madness? (look for it on google) It is a quick and easy way to build muscle fast.
Elated I found this film. Youtube is perfect for this kind of content.
My step brother was formerly bullied. He said he was going to get bigger. I laughed… Then in just weeks he gained 40lbs of genuine muscle mass. He made use of the Muscle Building Bible (look in Google). No-one dares to intimidate the man anymore. 🙂 I subscribed the other day. See exactly what goes on. Not to mention this mans emails are fucking excellent…
thank you so much for posting these.thery are really helping me with my biology a level
whew. What a relieve. Thanks so much. I love the way you go over those steps before you start a brand new step. Love it. Thanks for posting
In Step 4 where does the ATP that binds to Myosin come from?
My class average on my A&P exam was a 65, I watched these videos and got a 93, i love you good sir, thank you!
Read 25 pages of my A&P book had no idea what they were flapping on about… thank you so much for making this so simple!!
great teaching!!
does the myosin have to move the whole way across the actin? or is it some kind of graded response where the myosin can also move halfway if it likes?
Do you have a lisp??
sure is right. even i was very sad since i workout well for abs but nothing was coming. Listen to this I saw an interview with body building champion where he talks about 7 odd foods he eats to keep his abs hard. get to know here -> bit.ly/10OySTl?=ubgor
sure is right. even i was very sad since i workout well for abs but nothing was coming. Listen to this I saw an interview with body building champion where he talks about 7 odd foods he eats to keep his abs hard. get to know here -> bit.ly/10OySTl?=ubgor
The sliding of the actin over the myosin is incremental; in order for the two actin molecules to become so close, the actin-myosin reaction has to happen multiple times. The muscle can pull the actin as close to each other as it wants, as long as there is calcium and ATP to power each slide.
TL;DR it can be a graded response
If you’re asking immediately where it comes from at that instant, it is brought from mitochondria which are plentiful in muscle cells.
More specifically, within the mitochondria, the Citric Acid Cycle is used to convert the energy in glucose into smaller, more usable units of energy stored in ATP. The Citric Acid Cycle produces NADH and FADH2 which carry electrons to the Electron Transport Chain, which in turn produce ATP using ATPase in the mitochondrion. Search Google for more details.
thanks for the reply, sorry to be annoying but to clarify, so this sliding filament mechanism as well as the motor unit concept are both used in conjunction to give a graded response? would it be right to say that since increased action potentials stimulates more motor units?
Why can not you be my Physiology professor?? lol Thanks anyways
I think videos like this are the future of teaching, it’s just so much more effective than a textbook or teaching on a chalk board. You’re also a very talented teacher, thank you for making this.
I think videos like this are the future of teaching, it’s just so much more effective than a textbook or teaching on a chalk board. You’re also a very talented teacher, thank you for making this.
Excellent video!
I LOVE YOUU
If you desire to have an outstanding body, you should definitely Google search for “Aston Muscle Ripper”. You are going to end up getting the appearance you want.
Sir, you are truly amazing. Your videos have been incredibly helpful for me seeing the processes and applying the concepts and this video is no exception. Keep up the great work!
Thank you! Amazing, you helped me so much today.
This has cleared it up! Thank you SO very much!
THANK YOU !!!! you clarifyed so much !!!!
Thank you.. Your work is very much appreciated! Take care : )
your accent makes learning so much more bearable, great stuff! and very selfless to put it up on-line free of charge!
thanks a bundle
If you really want to get a six pack, you should take a look on Google for “Oak Muscle Method”. You are guaranteed to achieve the muscles you deserve.
Thank you so much for this video! I have a final tomorrow and I finally understand what my professor attempted to explain!
Where was your old six steps? Is there anyway I can still find it on your page ?
Never mind . Found it
Thank you
don’t know how people can’t like this!
thanxxxxxxxxxxxxxxxx
I love this guy’s accent! I feel like I’m learning a lot from him already!
Thank you so much for making and sharing this video! It helps me a lot. You’ve a lovely voice!
amazing video , 🙂 thank you for uploading this !
wow, wow, wow! you really make this simple and straight to the point….i have an exam in 3 days and i for once can say “im ready for the physiology paper”. thanks a lot you are really heaven sent to tutor me and GOD bless you
thank you! you explained it very well:)
Oh, shut up, Ameen!
This is just great!!! Thanks so much!
Step 1 can be expanded on a bit:
– AP traveling down T-tubule activates (Dihydropyridine) L-type Ca channels causing Ca influx
– Ca influx acts at Ryanodine Ca dependent Ca channels on the Sarcoplasmic reticulum causing the release of sarcoplasmic reticulum Ca stores.
– Ca then can bind to troponin C, etc, etc ,etc
Other than great video!
Step 1 can be expanded on a bit:
– AP traveling down T-tubule activates (Dihydropyridine) L-type Ca channels causing Ca influx
– Ca influx acts at Ryanodine Ca dependent Ca channels on the Sarcoplasmic reticulum causing the release of sarcoplasmic reticulum Ca stores.
– Ca then can bind to troponin C, etc, etc ,etc
Other than great video!
The top comment is practically the same, yet my comment gets disliked. Sounds fair.
Thank you!!! I really enjoy your presentations,very thorough. I really get a clear understanding everytime I watch your tuts. Really appreciate it!!
Tks : )
What is the funtion of Titine on muscle contraction?
This was very easy to understand. Thank you for the work you invested:)
THANK YOU!!! Instead of reading a boring 10 pages chapter (which takes me 2-3 hours to comprehend), I watch your 10 min video and understand everything! Very helpful especially if English is a second lang! ( I am Russian)
yes I agree cant even believe it. i know the bad fat is the reason that stopping 6 pack coming outside even we work out well. Listen The surprising part is my friend who is not doing much excercises, maintaining his six pack with this secret food items. check it out here bit.ly/10zdh63?=jrekr
Thank you so much for your time and energy. You have no idea how much this has helped me!
Thank you for your wonderful presentations. Please kindly make another video on action potential regarding Numbness ,when anaesthetic solution is injected at Axon terminal.
Extremely well done! Thank you, this is only video I’ve seen that has helped me understand.
you are correct. you can make your workout sessions much more productive if your eating the right foods to avoid fat and belly. Between In a best female model 2012 exclusive interview she had mentioned about her strong abs with this 7 food items. you can see it here bit.ly/17c5ASh?=pohpw
The lessons on skeletal muscle contraction were excellent! The lecture and the book gave me enough information to confuse me, but your presentation brought it all home!!!!
I now have you book-marked
Thanks!
yep i agree. even i was very sad since i workout well for abs but nothing was coming. And My international body building trainer also recommended this 7 food elements to kill your fat belly. you can watch out here bit.ly/12rlpky?=xedhl
Tx for the vid, haha the accent helps a lot its so much better to listen to than some other boring vids with monotone voices.
yes i mean it. you can make your workout sessions much more productive if your eating the right foods to avoid fat and belly. Listen to this In a best female model 2012 exclusive interview she had mentioned about her strong abs with this 7 food items. have a look here bit.ly/16ZDK9R?=zchmb
Titin is a giant protein that functions as a molecular spring which is responsible for the passive elasticity of muscle.
Thank you, I’ve learned so much by watching your videos!
yes I agree cant even believe it. i know the bad fat is the reason that stopping 6 pack coming outside even we work out well. But I saw an interview with body building champion where he talks about 7 odd foods he eats to keep his abs hard. if you are serious go for it now bit.ly/14jXzLt?=dmkty
THANK YOU! Because of you, I’ll be able to pass my quiz tomorrow.
Great explanation. I more understand it. God bless you! 🙂
Have you seen “Max Muscle Booster?” (do a Google search for it) It is a quick way to build muscle fast.
thanku very much i:am a 10 class grader and really appeariciate,,, ur video it actually helped me a lott and to understand every single step in binding
u are the best***
Very nice video!! Understood very nicely thanks a lott!!:)
☻☻☻☻☻☻☻☻☻☻☻ Sixpack Tips Unveiled ►→▷►►→⇨►⇨►→⇨►⇨
⇨►⇨⇨▷►►⇨ I heard that most of the celebrities used to follow to kill their belly using this 7 food items. ⇨▷→▷►⇨
☺☺☺☺☺☺☺ All people could do this. ⇨▷→▷►⇨
Do it here ▷→▷▷⇨▷⇨xnims.infosixpack
Hi Leslie, thanks for great videos they are so easy to understand and informative. However I did missed one think in muscle contraction video, at school in the UK we been talk about the cross bridge, can you explain me which part of the contraction called cross bridge.
Thank you!!
thank you mr InteractiveBiology
Thank you for making sense
i have physiology right now and you sir saved me a whole bunch. REALLY love your videos. very simple to understand and enjoyable!!!!
wish u were the professor…
Awesome, stay blessed 🙂
Wow, you are a great teacher. Your voice, your animation, your simplicity, and the steps you go over and over makes it soooo simple to learn!!!! Awesome! :)))))
thank you very much
Is this the same process in heart cells???
you rock
I got it ~~~ thanks alot ~~~~
Really good breakdown good job
Great Vid
wow. he makes it so clear.from now on im going to watch all of his video
VERY helpful!!! I never would have got this concept without this video!!!
VERY helpful!!! I never would have got this concept without this video!!!
Great teaching, I actually learned it, super simple!
Thanx pretty much
best explanation tnx
Very good… 🙂
khan academy
what is the role of that MG2+ ion shown in the picture