Many composite layup designs also include a co-curing or post-curing of the prepreg with various other media, such as honeycomb or foam. This is commonly called a sandwich structure. This is a more common layup for the manufacture of radomes, doors, cowlings, or non-structural parts.
Troponin is a protein that helps hold tropomyosin in place on the actin filament. A muscle contraction consists of a series of repeated events. First, calcium triggers a change in the shape of troponin and reveals the myosin-binding sites of actin beneath tropomyosin. Then, the myosin heads bind to actin and cause the actin filaments to slide. Finally, ATP breaks the actin-myosin bond and allows another myosin 'oar stroke' to occur. Repetition of these events causes a muscle to contract. Learning Outcomes. After this lesson, you'll be able to: Identify the structure of myosin and actin
Upon receiving a signal from a neuron, the muscle cells open the calcium channels in their cell membrane, and the calcium ions rush in due to the voltage difference between the inside and outside of the cell. These ions then interact with actin and myosin filaments to cause muscle contraction. The muscles remain in the contracted state until adenosine triphosphate (ATP) binds to myosin, releasing the myosin and actin filaments from one another.