life processes in the biosphere

what is range of tolerance

the limits of environmental conditions that a species can survive

name some factors that determine survival of a species

Biotic

• food supply

• pollination

• seed dispersal

• disease

• mates

Abiotic

• light

• pH

• water

• mineral nutrients

what is a sere

a process of stages in ecological succession where an uninhabited area develops into a climax community

what are the 3 seres

hydrosere - water

lithosere - rock

psamosere - sand

what is the name of the first species that colonises an area

the pioneer species

what is a climax community

the final species that is left after ecological succession

what is a plagioclimax community

the final species left after humans interrupt ecological succession

why do humans maintain a plagioclimax community

sometimes they benefit us

e.g. wheat, corn, grass

what is secondary succession

the process where an ecosystem recovers after a natural/human disaster

(happens on land that’s had previous colonisation)

what is an R-selected species

a species that can reproduce quickly as they give both to many young

what’s a k-selected species

a species that reproduces slowly and gives birth to few young

what is a density dependant factor

factors that population has an effect on survival rate

food supply

disease

what’s a density independent factor

factors that population has no effect on survival

volcanic eruptions

floods

what is carrying capacity

the greatest population that an area of land can sustain indefinitely without damaging the environment

what is predator-prey population relationship

when the population of prey is high so the predator population decreases leading to more predation so prey population declines so less food for predators so predator population declines and their populations fluctuate

what is taxonomy

the study of grouping organisms according to their similarities

what is a species

groups of closely related organisms that can breed together to produce fertile offspring

what is evolution

the process that changes the gene pool of a species by genetic mutations

what is an ecological niche

the role a species plays in its habitat

what is population

the total number of a species in an area

what is a community

the total number of individuals of all species in an area

what is an ecosystem

the combination of all the biotic and abiotic factors in an area

what is a biome

a large geographical region with specific climatic conditions and native species

what is the biosphere

all of the planet that is inhabited by living organisms

what are the stages of succession

• new area emerges

• pioneer species moves in and changes environment (usually moss/algae/small plants)

• when they die and decompose SOIL forms (makes it more hospitable)

• intermediate species move in as they can make roots

• this process repeats and larger plants colonise

• a climax community forms