If you know that the renal clearance of substance x is zero, which of the following can you say is true about how the kidney handels x?
a. x is filtered, not reabsorbed, and additional is secreted
b. x is either not filetered or filtered and completely reabsorbed
c. x is not filtered
d. x is filtered and completely reabsorbed
e. x is filtered, not reabsorbed, not secreted

i think the answer is gold im not entirely sure

make   gliitsh plesea   !

it provides an alternative energy pathway for the reaction to proceed.

a catalyst is a substance that speeds up the rate of a chemical reaction but is not consumed during the course of the reaction.

catalysts increase the rate of reaction without being used up. they do this by lowering the activation energy needed. with a catalyst, more collisions result in a reaction, so the rate of reaction increases. different reactions need different catalysts.

a catalyst works by providing an alternative reaction pathway to the reaction product. the rate of the reaction is increased as this alternative route has a lower activation energy than the reaction route not mediated by the catalyst.

there's no big difference.

explanation:

the only little different between a rabbit and bunny is just that bunnies are much smaller than rabbits. bunnies are basically baby rabbits.