`1 what happens when an action potential reaches the end of the axon a the potassium ions travel back towards the cell body b the neuron takes up chemical messengers (neurotransmitters) c the sodium ions travel back towards the dendrites d the neuron releases chemical messengers (neurotransmitters)

Which statement describes the reaction for cellular respiration? the equation is carbon dioxide + water → glucose + oxygen + water and energy is required in the form of light the equation is glucose + oxygen → carbon dioxide + water and energy is produced in the form of atp. the equation is carbon dioxide + water → glucose + oxygen + water and energy is produced in the form of atp. the equation is glucose + exygen carbon dioxide + water and energy is required in the form of light.

Liquid water turns into water vapor at which step in the water cycle? a. precipitation o b. water run off c. evaporation d. condensation

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