Which of the following correctly describes how a diagram of cellular respiration would differ from a diagram of photosynthesis

Match the following terms describing electrical events with the correct phases of the cardiac cycle. the ventricular muscle cells depolarize at the start of this phase. during this phase, na+ entry through the funny channels causes the pacemaker potential of sa nodal cells to gradually become less negative until it reaches threshold. the ventricular muscle cells repolarize right before this phase. the cytosolic concentration of calcium in the contractile cells of the ventricle is highest during this phase. a. isovolumetric relaxation b. ventricular ejection c. isovolumetric contraction d. ventricular filling

What is thought to have caused the mass extinction at the end of the cretaceous period?

If animal agriculture was eliminated, how much grain would become available for human consumption?