<span>Enzymes are Biological Catalysts. They increase the rate of Metabolic reactions. Almost all Biological Reactions involve Enzymes. All enzymes are Globular Proteins with a specific Tertiary Shape. They are usually specific to only one reaction.</span><span>The part of the Enzyme that acts a Catalyst is called the Active Site. The rest of the Enzyme is much larger and is involved in maintaining the specific shape of of the Enzyme.</span><span>When a reaction involving an Enzyme occurs, a Substrate is turned into a Product. The Substrate can be one or more molecules. The Active Site of an Enzyme is Complementary to the Substrate it catalyses.</span>
To confirm the above hypothesis, Maria should perform an experiment to prove that xylem is responsible for the transport of coloured water through the plant. This is called the ascent of sap.
A suitable plant having a tender, semitransparent stem should be selected. The root system of the plant should be cut off and the twig has to be placed half-immersed in a coloured solution of water for about one hour. Later, when the plant is observed, parallely running streaks of coloured water can be seen through the semitransparent stem and other parts of the plant indicating that the xylem is involved in the upward movement of water.
Vacuole. Amoeba is a unicellular organism formerly grouped under Kingdom Protista. Amoeba in freshwater need contractile vacuole to control input and output of water. (osmosis). Without this structure, ameboid cells will be filled with water and eventually burst.