ANIMAL ORIENTATION RESPONSES
=KINESES= A Kinesis is a non-directional response to the intensity of a stimulus (non-directional) '''Kineses usually involve movement of whole organism (motility), rather than growth''' '''Kineses are ''non-directional'' so they are neither positive nor negative''' ==Examples== [image:http://i.imgur.com/3ur4LnV.gif] Many insects will move much faster (in no particular direction) when placed in direct sunlight, this is known as a ''photokinesis''. This ensures they spend less time in direct sunlight where they would be at risk of desiccation (water loss) and predation. Lice will move more slowly and turn more often (so that they stay in the same place) when in warmer environments -like a person's head! This is known as a ''thermokinesis''. It is important to realise that although these responses are not directional the organisms will spend more time in their preferred environment as a result. Left is a model that shows a population of organisms. Each individuals moves randomly, but they move more slowly in the dark and therefore are found more often / spend longer in the darker region. ==Types of Kineses== [image:http://i.imgur.com/wK4J2fJ.png?1] '''Orthokineses''' The intensity of stimulus determines the ''rate of movement'' (speed). For instance Slaters move faster in bright light and slower in dim light, they also move slower in humid conditions and fast in dry conditions. You can that the beetles (left) move faster in the area of high light intensity and slower in the darker half. Although this means that they will tend to spend more time in the darker half, this is '''not''' a directional response (some of the beetle are moving in completely opposite directions). [image:http://i.imgur.com/YSY3dNa.png?1] '''Klinokineses''' The intensity of stimulus determines the ''rate of turning''. For instance, lice will turn more frequently in warmer conditions. This prevents them from getting too far away from their nice warm host. You can see that the lice (left) move turn far more frequently in the warmer area. Again, although this means that they will tend to spend more time in the warmer half, this is '''not''' a directional response (some of the beetle are moving incompletely opposite directions).
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