Natural selection gets rid of those who are unfit of surviving and allows those who can survive to reproduce and live on
Answer:
<em> It explains how nature works.</em>
Explanation:
A scientific theory can be described as a descriptive explanation of the occurrence of any phenomenon taking place in the natural world. Other statements are not true because a scientific theory is explained best with the help of certain experiments and certain known facts. It might be based on results from many experiments and supported through many known facts. A scientific theory has the capacity to replicate its results when performed again and again.
Striated muscles contain repeating sarcomeres of overlapping arrays of long, thin actin and thicker myosin filaments. Myosin filaments contains the myosin heads, which are enzymes that can bind to actin, split and make use of the energy from ATP. When muscle contraction starts, myosin heads bind to actin, change their configuration on actin, liberating the products of ATP hydrolysis and causing slide of the actin and myosin filaments. The action of the proteins troponin and tropomyosin on the actin filaments regulates vertebrae striated muscle contraction. The release of calcium ions from the sarcoplasmic reticulum is triggered by the nervous stimulation which causes depolarization of muscle membrane. Calcium ions bind to troponin and thus cause or allow the tropomyosin strands on the actin filament to move so that the part of the actin surface where myosin heads need to bind is uncovered. Contraction then occurs and only stops when the sarcoplasmic reticulum pumps calcium out of the muscle interior.
So basically, what triggers the uncovering of the myosin binding site on actin is the calcium ions binding to troponin and changing configuration.
you go to Cyprus? Miss roach?
