Basic Biochemistry

The Chemical Context of Life

Hierarchy of Biological Order

Atoms• Building block

of matter.• Composed of

protons and neutrons in the nucleus.

• Negatively charged electrons in orbits around nucleus

• They have mass• They interact and bond to

make molecules.

Ions

• An atom with a net + or – charge because it has either lost or gained an electron.

• Examples: H+ , Cl-, Na+

Molecules• Molecules are formed by 2 important

bonds: ionic and covalent.

• Ionic bonds are formed between ions. The positively charged ion attaches to the negatively charged ion.

Molecules• Covalent bonds are formed when atoms

share elections.

Hydrogen bonds

• Weak bonds formed between + charged H atom of H2O and the slightly – charged atom of oxygen of another H2O molecule.

This leads to important properties of water:• Cohesion, • Surface tension, • Capillary action, • Stable temperature, • Universal solvent.

Water

Organic Chemistry• The study of chemistry that specializes in the study of carbon.

• Functional groups: clusters of atoms that attach to carbons.

4 Major Macromolecules

• Carbohydrates

• Lipids

• Nucleic Acids

• Proteins

Carbohydrates• Sugars• Energy source• Provide storage and

structure• Monosaccharide-

simple sugarsEx. C6H12O6

Glucose

Carbohydrates

• Disaccharide- two sugars

• Polysaccharide- many sugars

Lipids• Fats, Oils, Steroids

• Insoluble in water

• Fatty acid chains attached to glycerol

• Important examples: phospholipids, steroids

• DNA & RNA

• Made up of nucleotides: sugar, phosphate, and nitrogen base

Nucleic Acids

Proteins• Many important

jobs in structure and function of living things.

• Nearly all proteins are enzymes.

• Made up of the 20 amino acids.

Proteins

Proteins must have a specific shape and structure. If the structure is destroyed, the function is also destroyed.