2.1 species and populations Flashcards
limiting factors
- resources in the environment that limit the growth, abundance and distribution of organisms/populations in an ecosystem
carrying capacity
- maximum number of species a habitat can sustainably support in a given area
ecosystem
- community of interdependent organisms and the physical environment they interact with
- made up of biotic and abiotic components
biotic components
- anything living
producers
- plants converting energy to matter
consumers
- animals that eat plants or other animals
decomposers
- organisms that breakdown waste into component parts to reuse
Interactions
- between living components
- predation, herbivory, parasitism, mutualism, disease, competition
species
- group of organisms with common characteristics
- can interbreed to produce fertile offspring
population
- group of individuals of the same species living in the same area at the same time
population size
births and immigration - increase
deaths and emigration - decrease
abiotic components
- non living things
temperature
sunlight
water
pH
salinity
precipitation
habitat
- environment in which a species usually lives
niche
- role an organism plays and the position it holds in the environment
- includes all interactions with biotic and abiotic factors
fundamental niche
- tolerance range for abiotic factors in their environment
realized niche
- part of the fundamental niche the species actually occupies
- usually defined by competition
limiting factors
density dependent
- impact the population only when it reaches a certain density
- competition, disease, parasitism, predation
limiting factors
density independent
- control populations regardless of density
- sunlight, temperature, water, natural disasters
J shaped curve
- exponential population growth
- ideal conditions, resources, limited competition
- population continues to grow until all resources have been used
- typical of r strategists
S shaped curve
- limited resources
- exponential growth short period of time
- resources depleted and plateau
- typical of k strategists
predation
- one organism hunts and kills another to provide it with energy for survival and reproduction
eg. lions hunting buffalo
herbivory
- consumption of plant material by an animal
eg. giraffe eating plants
parasitism
- an organism takes nutrients from another organism
eg. ticks and fleas
mutualism
- two organisms of different species exist in a mutually beneficial relationship
eg. corals and algae
disease
- departure from normal state of functioning of any living organism
eg. anthrax and herbivores in zimbabwe
competition
- organisms compete for a limited resource
intraspecific competition
- members of the same species compete for a limited resource
interspecific competition
- members of different species compete for a resource
