Final answer:
Increasing the starting substrate concentration initially increases the reaction rate, but there is a saturation point where further increase in substrate concentration does not affect the reaction rate.
Step-by-step explanation:
When there is an increase in the starting substrate concentration, the reaction initially goes faster. This is because the substrate molecules have a higher chance of colliding with the enzymes and forming the product. However, there is a point where further increase in substrate concentration will not affect the reaction rate because all of the enzyme's active sites become occupied with the substrate, reaching a saturation point.