Adaptations, interdependence and competition (7.1) Flashcards
What is an ecosystem?
the interaction of a community of living organisms (biotic) with the non-living (abiotic) parts of their environment.
What are species in ecosystem?
organisms that can reproduce to produce fertile offspring
What is a population in an ecosystem?
organisms of the same species in a habitat
What is a community in an ecosystem?
all the populations of organisms in a habitat
In order to survive and reproduce, what do organisms require?
a sufficient supply of materials from their surroundings and from the other living organisms there
What do plants in a community or habitat often compete with each other for?
light and space, and for water and mineral ions from the soil
What do animals in a habitat often compete with each other for?
food, mates and territory
4 examples
Within a community, what do each species depend on other species for?
food, shelter, pollination, seed dispersal etc
What is interdependence?
Within a community each species depends on other species (e.g. for food) and if one species is removed it can affect the whole community
What is a stable community?
One where all the species and environmental factors are in balance so that population sizes remain fairly constant
What are abiotic factors?
non-living factors
7 examples
What are the abiotic (non-living) factors which can affect a community
- light intensity
- temperature
- moisture levels
- soil pH and mineral content
- wind intensity and direction
- carbon dioxide levels (for plants)
- oxygen levels (for aquatic animals)
What are biotic factors?
living factors
4 needed
What are the biotic (living) factors which can affect a community
- availability of food
- new predators arriving
- new pathogens
- one species outcompeting another so the numbers are no longer sufficient to breed.
How may sunlight affect the distribution of species in an ecosystem?
light needed for photosynthesis
for making food sugar, etc
so more plants in sunny areas, less in shaded areas
