DNA

• DNA is made from two strands that are wrapped around each other in a twisting shape called a double helix.
• Each nucleotide is made up of three parts: a phosphate, a sugar, and a base.
• There are four different types of bases in DNA: A, T, C, and G.
• Each nucleotide has the same phosphate and sugar, but different bases.
• The sugar phosphate backbone of DNA forms a protective outer casing around the bases in the middle of the molecule.
• The bases on a single long chain of DNA hold the two strands in the double helix together.
• Only complementary bases can pair to each other, so A always pairs with T and G always pairs with C.
• The complementary sequence of a strand can be worked out by using the sequence of bases on the complementary strand.
• A gene is a particular sequence of bases that codes for a particular protein.
• Each group of three bases in a gene is called a triplet and codes for a specific amino acid.
• The amino acids that each triplet codes for are combined in the same order as the bases in the gene.
• The long chain of amino acids formed from the gene folds up all by itself and forms a protein.
• Each type of protein is made from a different sequence of amino acids, so each type will have a unique shape which allows it to carry out a particular function.
• Proteins have main uses in enzymes, hormones, and structural proteins.