3.4 Describe animal behaviour and plant responses in relation to environmental factors

1. 3.4Describe animal behaviour and plant responses in relation to environmental factors

2. Organisms responses • Stimulus (cue) - change in environment that causes a response in the organism • e.g. • A receptor – any cell or group of cells that can detect change • E.g. • An effector is a cell or group of cells that respond to the change • e.g.

3. Environmental Stimulus Receptors Sensory nerve impulse Central nervous system Motor nerve impulse Effectors Response

4. Receptors • PHOTORECEPTORS • Detect visible light,infra redandUV • Involve aPHOTOPIGMENT • Cells can be in an ORGAN • SOUND RECEPTORS • Mating calls or territory signals • Echo location • Cells are grouped into ORGANS • Ears

5. Receptors • GRAVITY RECEPTORS • Inform animal of its position and movement • CHEMO RECEPTORS • Detect chemicals in air, food, CO2 levels and blood hormones • Animals can produce PHEROMONES

6. Receptors • HEAT (THERMO) RECEPTORS • Detect changes in temperature • Within body or from touching environment • ELECTRICAL RECEPTORS • Some fish and sharks • Detect impulses emitted from organisms

7. Orientation Responses • Where an animal positions itself or carries out specific behaviours, when an environmental factor changes direction, duration, or intensity. • Can be • Simple e.g. taxes and kineses. • immediate movements in response to changes in factors such as light. • or complex e.g. MIGRATION or HOMING. • Help organisms avoid certain conditions and ensure survival and reproduction.

8. Taxis (pl. Taxes) • Movement of the whole organism towards or away from a stimulus coming from one direction. • Mainly animals and a few mobile plants e.g. Euglena swims towards light.

9. Positive Negative Taxis (pl. Taxes) • Movement towards stimulus POSITIVE • Movement away from stimulus NEGATIVE Stimulus temperature rise mosquito earthworm Direction determined by either body movements (klinotaxis) orby comparing stimulation of receptors on both sides of body (tropotaxis)

10. Examples Phototaxis Chemotaxis Geotaxis Thermotaxis Rheotaxis Positive Movement of earthworms Negative

11. Examples Phototaxis Chemotaxis Geotaxis Thermotaxis Rheotaxis Positive Movement of body lice Negative

12. Examples www.nabis.govt.nz Phototaxis Chemotaxis Geotaxis Thermotaxis Rheotaxis Positive Movement of pipi when disturbed Negative

13. Examples Phototaxis Chemotaxis Geotaxis Thermotaxis Rheotaxis Positive Movement of a blow fly to meat Negative

14. Examples Phototaxis Chemotaxis Geotaxis Thermotaxis Rheotaxis Positive Movement of salmon at spawning time Negative

15. Kinesis (pl. Kineses) • Random movement response • Not related to direction of stimulus • Rate determined by intensity of stimulus • ORTHOKINESIS • e.g. slaters move fast in bright light and slower in dim light, they move slow in high humidity (damp) and fast in low humidity (dry) • Where do they end up ?

16. Kinesis (pl. Kineses) KLINOKINESIS • Stimulus intensity determines rate of turning • e.g. human louse will turn frequently at high temperature • Where do they end up ? 35oC 30oC

17. Migration • Regular movements of large groups of animals – often annual • To find food • To breed • Long distance/risky/costly • e.g. birds, whales, eels, seals, whitebait, salmon, turtles, • Migration is under genetic control • Initiated by day length (change in season).

18. Activity • Biozone p175-176

19. Types of Migration • Dispersal- one way • Return migration • Nomadic migration- directionless • Remigration circuits- may involve more than one generation. • Migration is initiated by the activity of internal clocks, in response to environmental cues such as day length or change in temperature.

20. Activity • Biozone p 177- 178 • Extension work- Pheromones p174.

21. Homing & Navigation • Ability of animals to find their way home over unfamiliar territory. • e.g. homing pigeons, albatrosses, bees, limpets, frogs and toads. • Result of unusual events (e.g. storms) or movements in search of food, mates, breeding sites etc.

22. Navigation • Use of environmental cues for orientation examples include: • Landmarks- period of learning required before it can be used. • Magnetic fields/ compass- crystals of magnetite present in sensory system, e.g. bees, pigeons. • Sun compass- Suns position in sky changes with time of day. E.g. bees.

23. Stars- complex pattern of points. Young nestling birds imprint pattern at early age. • Smells e.g. ants to get home or allow others to follow. Salmon memory of native stream. • Travel time

24. Summary • Animals have sensory cells • Respond to stimuli • Send nerve impulses to CNS • CNS sends impulse to effector • Animals change orientation (position) • Simple TAXES and KINESES • Complex MIGRATION and HOMING • These benefit organism either by more food or better breeding

25. Word grid for matching pairs

26. BEHAVIOUR Observable response to a stimulus STIMULUS Change in organism or environment that causes response SENSE ORGAN Organ used to detect stimuli PHOTORECEPTOR Cell or organ sensitive to light EFFECTOR Organ the responds to a message from CNS TAXIS Movement either too or away from the stimulus KINESIS Random movement of an organism to a stimulus ORIENTATION RESPONSE General movement of an animal caused by a stimulus POSITIVE THERMOTAXIS Movement towards a heat source MIGRATION Regular, annual, mass movement of a population HOMING Ability of an animal to find its way home CNS Brain, spinal cord and nerves

27. HOMING Ability of an animal to find its way home CNS Brain, spinal cord and nerves STIMULUS Change which causes a response PHEROMONES Chemicals to communicate between animals of same species CHEMORECEPTORS Receptors that are sensitive to chemicals KLINOTAXIS Body movements used to sense the direction of stimulus TROPOTAXIS Comparison of two or more receptors on sides of the body RHEOTAXIS Animal movement in relation to water currents GEOTAXIS Animal movement in relation to gravity PHOTOTAXIS Animal movement in relation to light intensity ORTHOKINESIS Rate of movement linked to intensity of stimulus KLINOKINESIS Stimulus intensity determines rate of turning