Convection occurs because heated material becomes . A less dense and rises B denser and rises C denser and sinks D less dense and sinks

A less dense and rises

Explanation:

Convection is a type of heat transfer happens when there is a movement of fluid (liquid or gas) in which convection currents are produced due to the movement of hot fluid upwards and cold fluid downwards. This happens as the density of hot fluid decreases due to presence of less number of mmolecules per unit volume. As the hot liquid becomes less dense, it starts moving upwards.

Thus convection occurs because heated material becomes less dense and rises.

the binding of the substrate is dictated by the shape of each molecule. side chains on the enzyme interact with the substrate in a specific way, resulting in the making and breaking of bonds.