How does the release of calcium ions regulate muscle contraction?

Tropomyosin is a protein that covers the actin binding site. This prevents a cross-bridge forming between the myosin and actin filaments whilst the muscle is at rest. Calcium ions bind to troponin molecules, changing their shape. This change in the troponin moves the tropomyosin away from the actin binding site enabling the myosin head to attach. When the muscle relaxes, calcium ions are removed and the tropomyosin returns to its original position.

Answered by Emily T. Biology tutor

4273 Views

See similar Biology A Level tutors

Related Biology A Level answers

All answers ▸

When a vaccine is given to a person, it leads to the production of antibodies against a disease-causing organism. Describe how. (5 marks)


what are three main functions of the human liver?


Relate the structural adaptations of lumbar vertebrae to their functions (6 mark).


What are the differences between glycogen, starch and cellulose?


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences