Ecosystems, Succession and Competition Flashcards
What are populations?
The total number of individuals of one species in a given area, at a given time.
What are communities?
The different species living in the same area at the same time.
What is an ecosystem?
All of the living and non living parts in an area and how they interact.
What is a niche?
The area that an organism lives in and what it does there.
What does biotic mean?
Give examples.
Living parts of an ecosystem.
Such as predators, pathogens, prey, mates etc
What does abiotic mean?
Non living parts of ecosystem.
Such as soil pH, temperature, rainfall, space etc
What is carrying capacity?
The total number of organisms that an area can support without causing environmental damage.
What is intraspecific competition?
Individuals of the same species compete with each other for food and resources.
What is interspecific competition?
Individuals of different species compete for resources.
What are predators?
Animals that hunt and kill others.
Describe the shape of a predator prey graph.
As prey populations rise, predator populations rise as there is more foot to support them. However, if predator population gets too high, there will not be enough prey to feed all, so some die. Therefore, predator populations fall.
Why do 2 species never have the exact same niche?
They outcompete each other as there will not be enough resources to support both.
What happens when niches of 2 species overlap?
Species compete with each other and over time, one will be more successful than the other, so they die out.
What do food chains show?
Movement of energy through organisms.
What is the competitive exclusion principle?
When populations of 2 species initially occupy the same niche, one species tries to avoid competition.
What is a habitat?
The location that an organism lives in.
Why do we use a logarithmic scale when plotting growth curves?
Population growth can be extremely rapid, for example, when measuring bacteria growth
What is succession?
Ecological succession is the process of change in the species that make up an ecological community over time.
In succession, how might the presence of new species in an area change the population size of existing species?
The environment may be less suitable for the old species, so they die out while new one colonises.
In succession, how might a change in habitat benefit new species but damage old ones?
New ones may be better adapted, old ones may not be and therefore die out.
What is primary succession?
Organisms colonise a lifeless habitat.
What is secondary succession?
Organisms recolonise a devastated ecosystem, such as after a forest fire.
What are pioneer species?
Species that first colonise an inhospitable environment.
What is climax community?
Where the community established after succession remains stable for a long period of time.
Give 3 examples of things that may emerge as a result of succession.
More complex food webs
Increased biomass
Greater number of habitats and niches
Abiotic environment hostility decreases
What is conservation?
Where succession is prevented to protect habitats.
