Ecology And Energy Transfers 5.1-5.4 and 5.10-5.11 Flashcards
Define ecosystem:
All the organisms living in a particular area and all the abiotic factors
Define habitat
The place where an organism lives
Define population:
All the organisms of ONE SPECIES in a habitat
Define population size (same as abundance):
The number of individuals of one species in a particular area
Define community:
ALL of the organisms of DIFFERENT SPECIES that live in the SAME HABITAT and INTERACT with each other
Define abiotic factors:
Non-living feautures
Define biotic factors:
Living feautures
Define distribution:
WHERE a species is within a particular area
What causes population size to vary?
Abiotic and biotic factors
How do abiotic factors affect population size? (Ideal and non-ideal)
Ideal:
When temp of surroundings is optimum for metabolic reaction.s less energy used trying to maintain body temp so more energy used for growth and reproduction so population size will increase
Non-ideal:
Temp is lower or higher than optimum body temp they require lots of energy to maintain right body temp so less energy available for growth and reproduction so pop size will decrease
What 3 ways do biotic factors affect population size?
Interspecific competition = competition between different species
Intraspecific competition = competition within a species
Predation
Pop size: How do biotic factors affect interspecific competition?
Organsims of different species compete for the same resources so availability is reduced. Populations then limited by lower amount of food so less energy for growth and reproduction so pop size decreases for those species.
Pop size: How do biotic factors affect intraspecific competition?
Pop of a species increases when resources are plentiful so more organisms competing for same amount of space and food - become limiting so pop begins to decline - smaller pop mesns less comp for food and soave so more growth and reproduction = a cycle
What is the carrying capacity?
The maximum stable population size of a species that an ecosystem can support
Pop size: How do biotic factors affect predation?
Population sizesof predators and prey are interlinked
As prey pop increases = more food for predators so predator pop grows = more prey eaten so prey pop falls = less food for predators = pop decreases etc.
What causes distribution to vary?
Abiotic and biotic factors
How do abiotic factors cause distribution to vary? (Examples)
- Some plants only grow on south-facing slopes due to solar input
Some plants dont feow near to shoreline as soil is too saline - Large trees cant grow in polar regions because temp is too low
How do biotic factors cause distribution to vary? (Examples)
Interspecific competitiom affects ditribution
If two species are competimg but one is better adapted, less well adapted species will be outcompeted and wont be able to co-exist
Define niche
The role a species plays within a habitat which includes biotic interactions (what it eats etc) and abiotic interactions (oxygen breathed in)
What does it mean ‘every species has a unique niche’
A niche can only be occupied by one species
How does a species niche affect pop size?
Two species occupying similar niche will compete so fewer individuals for both species
How does a species niche affect distribution?
Organisms can only exist in habitats where all the conditions that make up their role exisy