Which of the following are roles that ions play in living things? Maintaining an acid/base balance in an organism

maintain the balance of water in cells

regulate what substances cross cell membranes

help regulate your heartbeat

Asolution of an enzyme and a substrate was placed in a water bath and the temperature of the reaction was raised gradually. the graph shown was plotted at the end of the experiment. what can be concluded from the graph? a) temperature has no effect on the activity of the enzyme. b) the effect of temperature on the enzyme is unpredictable. c) the enzyme shows increased activity up to a certain temperature. d) the activity of the enzyme is inversely proportional to the temperature.