Topic 4 - Muscle Contraction Flashcards
1
Q
Describe Myosin filaments
A
- They have globular heads that are hinged, so they can move back and forth
- Each head has a binding site for Actin and one for ATP
2
Q
Describe Actin filaments
A
- Have binding sites for myosin heads (actin-myosin binding sites)
- Tropomyosin (A type of protein) is found between actin filaments. It helps myofilaments move past each other
3
Q
What is tropomyosin?
A
A protein found between actin filaments attached to another protein. Together the two proteins help myofilaments move past each other
4
Q
Why can myofilaments not slide past each other in resting muscles?
A
Because the actin-myosin binding site is blocked by tropomyosin, which means the myosin head cannot bind to the actin-myosin binding site
