Macromolecule Reading Worksheet (Page 2 of 4) in pdf

properly. The place where a substrate fits an enzyme to be catalyzed is called the active site. Excess heat, a

change in pH from neutral, etc. change the shape of enzymes and their active sites so the enzyme is unable to

work. Some enzymes have a second site where a coenzyme attaches to help make the substrate better fit the

active site of the enzyme.

Condensation (removal of a water molecule) links amino acids link together to form chains called

polypeptides. Polypeptide chains join to form proteins. The bonds holding amino acids to each other are

known as peptide bonds.

Lipids are large, nonpolar (won't dissolve in water) molecules. Phospholipids make up cell membranes.

Lipids also serve as waxy coverings (cuticle) on plants, pigments (chlorophyll), and steroids. Lipids have more

carbon and hydrogen atoms than oxygen atoms. Fats are made of a glycerol (alcohol) and three fatty acid

chains. This subunit is called a triglyceride. Color the glycerol molecule using the same colors for carbon,

hydrogen, and oxygen as you did before. The fatty acid chains may be saturated (only single bonds between

carbons) or unsaturated (contain at least one double bond). A carboxyl functional group (-COOH) is found on

the end of the fatty acid that does NOT attach to glycerol A special type of lipid called phospholipids help

make up the cell membrane. Two layers of these phospholipids make up the membrane. Phospholipids have

a "water-loving" hydrophilic head and two "water-fearing" hydrophobic tails.

Nucleic acids carry the genetic information in a cell. DNA or deoxyribose nucleic acid contains all the

instructions for making every protein needed by a living thing. RNA copies and transfers this genetic

information so that proteins can be made. The subunits that make up nucleic acids are called nucleotides.

The parts of a nucleotide --- sugar (5-sided)-green, phosphate group (round)-yellow, and nitrogen base (6-

sided)-blue. ATP used for cellular energy is a high energy nucleotide with three phosphate groups.

Macromolecule Reading Worksheet Page 2