You isolate some muscle fibers to examine what regulates muscle contraction. When you bathe the muscle fibers in a solution cont
aining ATP and Ca^2 , you see muscle contraction (experiment 3). Ca^2 is necessary, as solutions containing ATP alone or nothing do not stimulate contraction and thus the muscle remains in a relaxed (uncontracted) state (experiments 1 and 2). From what you know about the mechanism of muscle contraction, fill in your predictions of whether the muscle will be contracted or relaxed for experiments 4, 5, 6 and 7. Briefly explain each of your answers.
Experiment 4. Relaxed, the drug will stop the calcium so that it does not act on the troponin
Experiment 5. Contraction: In order for the muscle to relax, the actin and tropomyosin union must occur.
Experiment 6. Relaxation: the release of the actin-myosin complex occurs with consumption of ATP, thus it slides and generates contraction, by adding a hydrolyzable analog, this reaction is avoided giving rise to a prolonged actin-myosin binding which leads to relaxation while last effect.
Experiment 7. Ca2 + Contraction is very necessary so that during muscle contraction troponin can be extracted.
For early earth, it was filled with loads of oxygen and could kill humans if they breathed the oxygen that was in the air about 100 million years ago. This massive amount of oxygen cause massive creatures like the dinosaurs to exist. Current earth has an atmosphere with not too much oxygen.
