Page 1 (As) Flashcards
Activation energy
Energy required to bring about a reaction.
the activation energy is lowered by the presence of enzymes
Active immunity
Resistance to disease resulting from the activities of an individuals own immune system whereby an antigen induced plasma cells to produce antibodies
Active site
A group of amino acids that makes up the region of an enzyme into the which the substrate fits in order to catalyse a reaction.
Active transport
Movement of a substance from a region where it is in a low concentration to a region where it is in a high concentration.
Process requires expenditure of metabolic energy
Aerobic
Connected with the presence of of free oxygen. Aerobic respiration requires free oxygen to release energy from glucose.
Allele
One of a number of alternative forms of a gene.
Eg) the gene for the shape of pea seeds has 2 alleles.
Allergen
A normally harmless substance that causes the immune system to produce an immune response.
Allergy
The response of the immune system to an allergen
Antibotic
A substance produced by living organisms that can destroy or inhibit yeh growth of microorganisms
Antibiotic resistance
The development in microorganisms of mechanisms that prevent antibiotics from killing them
Antibody
A protein produced by lymphocytes in response to the presence of the appropriate antigen
Anticodon
A sequence of 3 adjacent nucleotides on a molecule of transfer RNA that is complementary to a particular codon on a messenger RNA molecule
Antigen
A molecule that triggers an immune response by lymphocytes
Antioxidant
Chemical which reduces or prevents oxidation.
Often used as an additive to prolong food shelf life
Apoplastic pathway
Route through the cell walls and intercellular spaces of plants by which water and dissolved substances are transported
