- Created by: An Di
- Created on: 23-09-19 12:14
Anabolic & Catabolic
Anabolic - Reactions of metabolism that construct molecules from smaller units. These reactions require energy in the form of ATP. e.g. photosynthesis.
Catabolic - The reactions of metabolism that break down larger molecules into smaller molecules. These reactions release energy.e.g. respiration.
+Each enzymes active site is specific to the reaction that it catalyses. They are specific in terms of size, shape and chemical make up.
+As enzymes are made of amino acids, the order of the amino acids determine the shapes of the active site.
Lock and Key Theory
+Suggests a specific substrate will fit into the active site of an enzyme.
+There is no change to the shape of the active site when the substrate binds.
+There is a strain on the bonds in the substrate and that causes a change to the substrate and the reaction takes place.
Induced Fit Model
+More accepted model - enzymes are not rigid structures.
+Enzymes can change shape slightly when it binds to the substrate to result in a tighter fit. The fit is induced.
+Enzymes that are secreted outside of the cell.
+Digestive enzymes are an example of extracellular enzymes.
+They are produced by specialised goblet cells but act on food by the gut.
+Function within the cell.
+They don't leave the cell and are found in the cytoplasm, chloroplast, mitochondria, nucleus, etc.
+They are retained inside the cell for internal use
+DNA polymerase is an example of an intracellular enzyme.
Organelles such as chloroplast and mitochondria need a lot of enzymes.
Extracellular & Intracellular Enzymes
+Both enzymes are made inside the cell but intracellular enzymes remain in the cell.
+Extracellular enzymes are produced in the cell but work outside the cell. Quite often digestive enzymes.