A phospholipid is a lipid made of a phosphate group with two fatty acids.
A second messenger is a molecule inside cells that acts to transmit signals from a receptor to a target.
Hoped this helped.
~Bob Ross®
Explanation:
In thermoplastics, the arrangement of monomeric units is linear and in thermosetting plastics, it is cross-linked. Thermoplastics are usually soft, weak and less brittle, so can get soften on heating and stiffen on cooling. They can be melted, remoulded and recycled easily.
The statement Bonds in the hydrogen peroxide are weakened in catalase's active site, allowing the chemical reaction to occur is the answer. Catalase is an enzyme in the liver that breaks down harmful hydrogen peroxide into oxygen and water.