48-hour FLASH SALE: Get 30% Off All Certificates and Diplomas! Hurry, sale ends on Thursday, 12th December 2019.

Claim My 30% Discount
Previous Topic Previous slide Next slide Next Topic
New course

This Course has been revised!

For a more enjoyable learning experience, we recommend that you study the mobile-friendly republished version of this course.

Take me to revised course.

- or -

Continue studying this course

Sliding filament theory

  • Study Notes
  • Discuss This Topic
    Zachary B.
    Zachary B.

    What is the sliding filament theory?

    Rk S.
    Rk S.

    Sliding filament theory:- For contraction to occur, a nerve impulse must be sent from the brain. Down at the motor end plate, calcium ions are released which effectively act as a power switch. This power switch activates the crossbridges (which connect thick and thin filaments). ATP energises the crossbridges, which allows a pulling action to occur, resulting in the thin filaments sliding over the thick filaments. This occurs all down the length of the fibre (at each sarcomere), and the result is a contraction of the muscle. What happens to each of the following when a muscle contracts? Actin - thin filaments: slide over the thick filaments; whether they slide toward or away from one another depends on whether it is a concentric or eccentric contraction Myosin - thick filaments; do not move under contraction Crossbridges - oar-like structures that are attached to the thick (myosin) filaments. These structures reach out and are attracted to the thin (actin) filaments. When contraction occurs, these oar-like structures drag the thin filaments in toward the centre of the sarcomere and the muscle contracts (concentric contraction) I band - distance between the z-line and the edge of the A band H zone - the gap between the thin filaments before contraction. The H zone disappears upon full contraction A band - the length of the thick filament Make sure you have a good look at a diagram of the sliding filaments (actin): one is on the previous page. It is quite possible that a question with a diagram will be used in the exam.

    Muhammad S.
    Muhammad S.

    What is the theory of sliding filament.

  • Text Version

You have received a new notification

Click here to view them all