What type of enzyme regulation happens when a molecule similar in shape to the original substrate binds to the active site preventing the enzyme from reacting with the substrate?

Competitive inhibition

Explanation:

Competitive inhibition is a form of enzyme control in which an inhibitor molecule, very similar in structure to the normal substrate of an enzyme, becomes reversibly bound to the active site.

A good example is malonate (an inhibitor) depriving succinate from binding to the active site of the enzyme, succinic acid dehydrogenase

Competition inhibition.

Explanation:

Competition inhibition happen when inhibitor compete with the substrate. This occur when an inhibitor which look like substrate bind to the enzyme at the active site thereby withholding the substrate from binding. Inhibitor are analogos because their structure look like the substrate. Example include antineoplastic drug methotrexate.

b. the carbon cycle ensures living things have a source of hydrogen