Mode of Enzyme Action Enzymes are globular proteins This means their 3D shape (as well as the shape of the active site of an enzyme) is determined by the complex tertiary structure of the protein t...
Enzymes as Catalysts Enzymes are biological catalysts ‘Biological’ because they function in living systems ‘Catalysts’ because they speed up the rate of chemical reactions without being used up or ...
Fibrous Proteins: Structure & Function Structure Fibrous proteins are long strands of polypeptide chains that have cross-linkages due to hydrogen bonds These proteins have little or no tertiary...
Globular Proteins: Structure & Function Structure Globular proteins are Compact Roughly spherical (circular) in shape Globular proteins form a spherical shape when folding into their tertiary s...
Levels of Protein Structure There are four levels of structure in proteins Three are related to a single polypeptide chain The fourth level relates to a protein that has two or more polypeptide cha...
Amino Acid: Structure Proteins Proteins are polymers (and macromolecules) made of monomers called amino acids The sequence, type and number of the amino acids within a protein determines its shape ...
Nature of the Genetic Code The triplet code The sequence of DNA nucleotide bases found within a gene is determined by a triplet (three-letter) code Each sequence of three bases (i.e. each triplet o...
Translation Translation occurs in the cytoplasm of the cell After leaving the nucleus via a nuclear pore, the mRNA molecule attaches to a ribosome In the cytoplasm there are free molecules of tRNA ...
Transcription A gene is a sequence of nucleotide bases in a DNA molecule that codes for the production of a specific sequence of amino acids, that in turn make up a specific polypeptide (protein) T...
