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Active immunity

1. Immunity induced in the host itself by antigen and lasts much longer, sometimes lifelong. (wikipedia.org) 2. A form of acquired immunity in which the body produces its own antibodies against disease-causing antigens. (wordnetweb.princeton.edu) 3. The immunity that results from the production of antibodies by the immune system in response to the presence of an antigen. (Google Dictionary) 4. A type of immunity or resistance developed in an organism by its own production of antibodies in response to an exposure to an antigen, a pathogen or to a vaccine....

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Active Transport

Noun 1. The movement of a substance across a cell membrane against its concentration gradient (from low to high concentration). In all cells, this is usually concerned with accumulating high concentrations of molecules that the cell needs, such as ions, glucose and amino acids. If the process uses chemical energy, such as from adenosine triphosphate (ATP), it is termed primary active transport. (wikipedia.org) 2. The movement of a chemical substance by the expenditure of energy against a gradient in concentration or in electrical potential across a plasma membrane. (merriam-webster.com) 3. The movement of ions or molecules across a cellular membrane from a lower to a higher concentration, requiring the consumption of energy....

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Active transport

1. A kind of transport wherein ions or molecules move against a concentration gradient, which means movement in the direction opposite that of diffusion – or – movement from an area of lower concentration to an area of higher concentration. Hence, this process will require expenditure of energy, and the assistance of a type of protein called a carrier protein. (biology-online.org) 2. The movement of materials across cell membranes and epithelial layers against an electrochemical gradient, requiring the expenditure of metabolic energy. (online-medical-dictionary.org) 3. The movement of a substance across a cell membrane against its concentration gradient (from low to high concentration). In all cells, this is usually concerned with accumulating high concentrations of molecules that the cell needs, such as ions, glucose and amino acids....

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Adaptation

/ˌadapˈtāSHən/ Noun, pl. adaptations 1. A trait with a current functional role in the life history of an organism that is maintained and evolved by means of natural selection. An adaptation refers to both the current state of being adapted and to the dynamic evolutionary process that leads to the adaptation. (wikipedia.org) 2. (Ecology) The adjustment or changes in behavior, physiology, and structure of an organism to become more suited to an environment. (biology-online.org) 3. (Ophthalmology) The ability of the eye to adjust to various light intensities by regulating the pupil of the quantity of light entering the eye. (biology-online.org) 4. (Neurology) The decline in the frequency of firing of a neuron, particularly of a receptor, to changed, constantly applied environmental conditions. (biology-online.org) 5. (Dentistry) a. The proper fitting of a denture. b. The degree of proximity and interlocking of restorative material to a tooth preparation. c. The exact adjustment of bands to teeth. (biology-online.org) Word origin: From French adaptation, from Medieval Latin adaptatio, from Latin...

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Adduct

tr.v. adducted, adducting, adducts 1.(Physiology) To draw inward toward the median axis of the body or toward an adjacent part or limb. (thefreedictionary.com) 2. A movement which brings a part of the anatomy closer to the middle sagittal plane of the body. It is opposed to abduction. (Wikipedia.org) 3. (Chemistry) A chemical compound that forms from the addition of two or more substances. (thefreedictionary.com) adduction (noun) adductive...

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