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L1 Micro-organisms
Level 1 NCEA Micro-organisms definitions
Term | Definition |
---|---|
ACQUIRED IMMUNITY | Immunity that develops after some contact with the micro-organism either through vaccination or natural exposure. |
AEROBIC | A form of respiration requiring oxygen in which energy-rich compounds (eg carbohydrates, fats) are broken down to produce adenosine triphosphate (ATP), which is the form of energy made available to cells for metabolic and catabolic reactions. |
AGAR | Polysaccharide extracted from seaweed used to set culture media into a gel |
ANAEROBE | An organism such as Tetanus bacterium that doesn’t need oxygen for respiration. A strict anaerobe is actually poisoned by oxygen. |
ANAEROBIC | Respiration that occurs in the cytoplasm in the absence of oxygen; may include the breakdown of energy rich compound (creatine phosphate) to make ATP but most anaerobic respiration involves glycolysis resulting in breakdown of glucose to pyruvic acid. |
ANTIBIOTIC | a substance produced by a living micro-organism which kills or inhibits the growth of another micro-organism eg penicillin produced by fungi (white part of bread mould), stops some bacteria growing and reproducing. It is taken internally. |
ANTIBODY | Protein made by the immune system in response to an antigen. The antibody binds with the antigen and inactivates it. |
ANTIGEN | Foreign substance (usually a protein in the toxin of the invading microbe) that can stimulate the immune system to produce white blood cells to attack it. |
ANTISEPTIC | a mild chemical that kills or inhibits the growth of some micro-organisms. Often used on skin, in mouthwashes etc. eg Savlon. H2O2 (hydrogen peroxide) and ethanol are common components of antiseptics to treat mild wounds. |
BACTERIA | A unicellular micro-organism with a protein coat surrounding its cell wall which is outside the cell membrane. (singular = bacterium). Reproduces using binary fission and feeds using extra-cellular digestion. |
BINARY FISSION | Method of reproduction where a cell makes a copy and splits into two. |
DISINFECTANT | stronger chemical to destroy (kill) or inhibit microbial growth – used on non-living surfaces eg toilet and walls etc eg bleach, Jeyes and Detol. |
ENZYME | a protein molecule that acts as a biological catalyst speeding up a chemical reaction by lowering the activation energy required for the reaction. Often name ends in –ase eg lipase, lactase. |
EXTRACELLULAR DIGESTION | the breakdown of large complex organic molecules outside the organism, into smaller, simpler materials, that can be readily absorbed and used by the organism; |
FUNGI | The largest micro-organism. Varies from one cell (yeast) to multi-cellular organisms (mushroom). Contains a hyphae and sporangia and spreads using spores. Feed through extra-cellular digestion. |
HYPHAE | plural of hypha: a branched thread-like tubular structure which forms the basic unit of the vegetative growth stage of fungi such as mushrooms, toadstools; |
MYCELLIUM | the networked mass of hyphae, which make up the bulk of a fungus |
IMMUNITY | The body’s internal protection system against micro-organisms which can cause disease and disrupt the body’s metabolism. |
INATE IMMUNITY | Bodily mechanisms that help protect the organism against any disease (non-specific) eg skin; tears. |
INOCULATE | the introduction of micro-organisms (the inoculum) or cells from a multi-cellular organism into a medium – usually agar. |
LYMPHOCYTES | White blood cells that are produced by the body for fighting infection. Two types – B and T lymphocytes. |
METABOLISM | Sum of all physical and chemical processes that take place in a living organism. Can be intra-cellular (in the cytoplasm of a cell) or extra-cellular (outside the cell eg digestive system). |
NANOMETRE | Unit of very small distance measurement. 1nm = 1/1000mm or 1 billionth of a metre. |
PASSIVE IMMUNITY | Antibodies made by another organism (eg mother) and passed on to another organism (eg baby). Can be passed on through placenta or breast-milk. |
PASTEURISATION | A process of heating a substance at a high temperature eg 70oC for a certain length of time eg 10mins, to kill microbes which would otherwise spoil the food. |
PATHOGEN | a micro-organism that causes disease in the plant or animal it infects. |
RESISTANCE | Some bacteria mutate (miscopy a nucleotide base on the DNA) and new strains (versions) of that bacteria can develop a resistance to an antibiotic which means it won’t work. |
RESPIRATION | a process of breaking down glucose using oxygen to produce energy (ATP). Carbon dioxide and water are waste products. |
SAPROPHYTE | an organism which feeds on dead or decaying matter in the form of organic substances in solution; such organisms play a key role in biodegradation and nutrient recycling. |
SPORANGIUM | plural sporangia; part of the fungus which produces spores |
SPORES | A small, usually single celled reproductive body form which a new organism arises when conditions are suitable for germination; spores contain no embryo which distinguishes them from seeds. |
TOXIN | a poisonous protein produced by bacteria, plants or animals; toxins act as antigens (a substance which triggers the production of an antibody). |
VACCINATION | Process of inserting dead or live micro-organisms to assist the body’s immune system in developing antibodies to fight that particular micro-organism. |
VIRUS | The smallest micro-organism which is always pathogenic to its host. Consists of protein coat, DNA or RNA and may have other appendages. Reproduces using the DNA of the host cell. |
WHITE BLOOD CELLS | Produced by the bone marrow and used to fight infection. Two types – phagocytes and lymphocytes. |