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Responsiveness — organisms respond to changes in their immediate environment long term changes is adaptability B. Growth — over a lifetime, organisms grow larger through an increase in size or number of cells. Differentiation is when cells have specialized functions C. Reproduction — Organisms reproduce, creating subsequent generations of similar organisms D. Movement — Organisms are capable of movement.
Site author Richard Steane. The BioTopics website gives access to interactive resource material, developed to support the learning and teaching of Biology at a variety of levels. Humans, Plants Variation, Ecology. Microbes Section. Biological physical chemistry?
Book: Passing. RESPONSE Taxis — simple response whose direction is determined by direction of stimulus, a motile organism responds directly to environmental changes by moving whole body towards a favourable stimulus or away from an unfavourable one Positive taxis — movement towards stimulusNegative taxis — away from stimulus Eg. Single — celled algae move towards light — positive phototaxis Kinesis — form of response, not movement towards or away from stimulus, the more unpleasant the stimulus, the more rapidly it moves and the more rapidly it changes direction — increase in random movements, important when stimulus is less directional Eg. Woodlice — lose water from their bodies in dry conditions, move more rapidly in dry area and change direction more often, move less in moist areas — prevents drying out and increases chance of survival Tropism — growth movement of part of a plant in response to a directional stimulus, plants grow towards or away from stimulus e. This material is available only on Freebooksummary.