The 21 amino acids can be arranged in many different ways. It is possible with just this small number of amino acids to create thousands of different types of proteins. Think of amino acids like they were little connecting blocks, such as legos. You have 21 of them before you. How many different ways can you arrange them? The formation of protein is similar.
Hey. The first sound is the "lub." This is what you hear once the mitral and tricuspid valves of the heart close, which are the valves between the atria and the ventricles! Super cool. It is your third answer choice.
Faces is the answer for ur question