Taxes and kinesis

• What are orientation behaviours?

  They allow organisms to move toward favourable environments or move away from unfavourable environments.
• Define taxis:

  The directional movement towards or away from a stimulus.
• Name the taxes for light, chemicals, gravity and temperature:

  Phototaxis, chemotaxis, geotaxis, thermotaxis.
• Define kinesis:

  A behavioural response of animals to the intensity of a stimulus. It is non-directional.
• Why do animals undergo kinesis?

  When they have a specific need but no information on the location of the needed resource.
• Suggest one advantage of a flatworm turning more and moving slowly in the shade and name the behaviour shown. (2)

  It remains in the shade so avoids predators. This behaviour is kinesis.
• Suggest and explain one advantage of kinesis to a human body-louse. (2)

  It stays in warmer conditions for longer, so it remains near a food source.