BIOCHEMISTRY A Review of Biology

MACROMOLECULES Macromolecules are polymers that are made of smaller pieces called monomers (building blocks) The four big macromolecules needed for your body are: –Carbohydrates –Lipids –Proteins –Nucleic Acids

CARBOHYDRATES Made up of sugars (building blocks) USE OF CARBOHYDRATES Main source of energy (cells burn glucose for their main source of energy during respiration)

TYPES OF CARBOHYDRATES Monosaccharides Disaccharides Polysaccharides

MONOSACCHARIDES Only one sugar molecule (simple carbohydrate) Example -glucose (C 6 H 12 O 6 )

DISACCHARIDES Double sugars (two sugars joined) Examples: sucrose and lactose

POLYSACCHARIDES Many sugars joined together (complex carbohydrates) Examples: starch and glycogen –Plants store excess sugar as starch –Humans store excess sugar as glycogen in the liver.

LIPIDS Include glycerides, steroids, & terpenoids USES OF LIPIDS Stored for energy Form basic structure of cell membranes Protection and insulation Help fight disease Help in many biochemical reactions

TYPES OF LIPIDS Glycerides – building block are fatty acids (long hydrocarbon chains with COOH at one end) –Includes triglycerides, saturated, and unsaturated fats Steroids – composed of 4 rings –Includes estrogen, testosterone, and cholesterol Terpenoids – polymers of short-chain fats –Includes vitamins A, D, E, and K

PROTEINS Many amino acids linked together (building blocks) USES OF PROTEINS Build living materials like muscle and hair Act as enzymes, which help carry out chemical reactions Fight disease (antibodies) Transport particles into or out of cells Act as markers on cells

AMINO ACID STRUCTURE

Nucleic acids are made of nucleotides (sugar, phosphate, and base) –Examples include DNA, RNA, and ATP NUCLEIC ACIDS USE OF NUCLEIC ACIDS Used in genetics and as an energy source

Enzymes are proteins. Enzymes work on substrates by either breaking them down or adding something to them –Example: Lactase breaks down lactose (sugar in milk) into its building blocks (glucose and galactose). ENZYMES

Each enzyme is specific and has a specific job. –The enzyme that breaks down starch (amylase) does NOT break down proteins. Most enzyme names end in -ase