Download Plant responses and Animal behaviour

Plant responses and Animal behaviour
The Environment: Abiotic and biotic factors
For an organism to grow, survive and reproduce they have to be able to take advantage
of changes in their environments. Its habitat, where an organism lives does not change,
but the environment can change dramatically (eg: Barnacle). An organism’s niche is its
‘way of life’ – how it lives in that habitat.
1. What does environment mean?
2. What are abiotic factors (physical factors)?
Environmental factors
o For a species to survive it must be able to reproduce. This requires that they have
suitable conditions for growth, are able to avoid being eaten and for sexual
reproduction are able to interact with others of the same species.
o The environment is all of these factors – biotic and abiotic. Various factors in the
organism’s environment are constantly changing.
o Organisms need to respond to environmental factors to survive and grow.
o Plants generally respond to the environmental factors by growth and by turgor
(changes in pressure of the cells) movements while animals generally respond by
movements.
o Organism must detect and respond to key physical factors to keep within their
optimum range.
Abiotic (physical) Factors
FACTOR
ASPECTS OF THE FACTOR
SIGNIFICANCE TO THE ORGANISM
light
intensity, duration, wavelength (colour of
visible light, UV and infrared)
photosynthesis, temperature, growth, camouflage,
vision
water
temperature
atmosphere
chemicals
vibrations
substrate
fire
Gravity
Touch
3. What are biotic factors?
Biotic factors
o The same species – intraspecific - and these interactions include;
Competition
Cooperation
Aggression
Reproduction
o Different species – interspecific – and these interactions include;
Competition
Cooperation or mutualism
Exploitation
Commensalisms
Analysis of effects of interactions
(+ beneficial, - harmful)
Interaction
Effect on Species 1
predation of species 2 by
species 1
mutualism
commensalisms of species1
with species 2
parasitism of species 1 by
species 2
competition between species
1 and species 2
Effect on Species 2
Responses of organisms to the environment
Environment = factors (abiotic and biotic)
Behaviour = response of the organism to environmental factors
Innate behaviour
Learned behaviour
*Sometimes behaviour is a mixture of the innate and learned.
Behaviour consists of 3 process:
a. Stimulus – change in environment
b. Receptor – any cell or group of cells that can detect the change
c. Effector – a cell or group of cells that respond to the change
4. Describe what is meant by ecological niche?
Adaptations are inherited in 3 ways:
(1) Structural =
(2) Behavioural =
(3) Physiological =