3.5 ecosystems Flashcards
biotic factors
predators
parasites
disease
intraspesific competition
competition between the same species
interspecific competition
competition between different species
abioic factors
food supply
temperature
light intensity
define biotic factors
caused by other living organisms
define abiotic factors
involve non-living components of the environment
describe the sigmoid growth curve
LAG PHASE- WHEN A POPULATIN FIRST ENTERS A NEW AREA
slow increase as it adjusts to its environment
LOG PHASE- RARE OF CELL DIVISON/REPRODUCTION IS AS MAX. population shows exponential growth
DECEDLERATION- RATE OF CELL DIVION SLOWS. due to presence of limiting factors (ex. food)
STATIONARY PHASE- BIRTH RATE= DEATH RATE. limiting factors prevent further increase and greater intraspecific competition
DECLINE PHA\SE- DEATH RATE GREATER THAN BIRTH RATE. lack of nutrients/ accumulation of waste and greater intraspesific competition
primary succession
bare ground
pioneer species (lichens)
increase humus
deflected climax
grazing, farming, deforestation
azotobacter
reduce nitrogen gs to ammonium ions
mutualistic nitrogen fixer
rhizobium
loves on roots of leguminous plants (bean)
ammonium ions to hydrogen ions and atp
nitrate ions to nitrogen gas
denitrification
bacterium that fixes nitroge
rhizobum
method in which nitrate ions pass into root hair cells
active transport
conversion of ammonium ions to nitrite ios
nitrification
