What is the function of proteins and carbohydrates that are embedded in a cell membrane? 1.they control what enters and leaves the cell. 2.they direct the reproduction process for the cell. 3.they act as storage molecules for water.

Answer : The correct answer is -

1.They help control what enters and leaves the cell.

Some molecules can not cross the lipid bilayer membrane (cell membrane) of cells (such as large polar molecules and hydrophilic molecules).

There are special carbohydrate and protein that are embedded in the membrane and act like Transmembrane channels or transporters, which assist in the trasport of such molecules (like amino acids and proteins) on both sides across the cell.

Thus, option 1) is the right answer.

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.