Myocardium, that's because myocardium simply means 'muscular tissue of the heart'. It is not pericardium or connective tissue as these are only small, specific areas of the heart and a heart attack can cause cells to die anywhere in the heart.
<em>Answer: Chromosomes </em>
<em>Depending on the organism, the number of chromosomes in a cell may change.</em>
The pulmonary vein carries oxygenated blood from the lungs to the left atrium
For the answer to the question above asking <span>In aerobic respiration, what is the direct source of energy that ATP synthase uses to synthesize ATP?</span><span>I think this is Proton Gradient. It is t</span><span>he product of the electron transport chain. A higher concentration of </span>protons <span>outside the inner membrane of the mitochondria than inside the membrane is the driving force behind ATP synthesis.</span>