I can see these are relating to enzymatically catalyzed reactions.
The first looks like it might relate to saturation. When more and more substrate is added, more enzymes have substrates to work on, so the rate of the reaction increases. But eventually a point is reached where all the enymes are actively processing substrates - there are no free enzymes that can handle any more substrates. Once the point of saturation is reached, one can increase the substrates to any level and there won't be an increase in the rate of the reaction.
The second looks like it deals with optimum pH for a given enzyme. When the pH is too high (basic) or too low (acidic) the enzyme stops functioning, Withing a range of pH, the enzymes functions, and within that range there is an optimal pH for function. This particular enzyme has an optimum pH that is pretty basic.
The third looks like it deals with temperature affect on enzyme activity. Too cold and the enzyme won't work (becomes too rigid). As the temperature rises the enzyme becomes able to function, and the rate of reactions increases with increasing temperature. But when the temperature gets too high the enzyme becomes denatured and loses its ability to function, and the rate of the reaction plummets.