Ecology Flashcards
What is ecology?
the study of relationships btw living organisms and btw organisms and their environment
What is a population?
a group of organisms of the same species living in the same area at the same time
What is a community?
a group of populations living and interacting with each other in an area
What is an ecosystem?
a community and its abiotic environment
What is a habitat?
the environment in which a species normally lives
What is a species?
a group of organisms that can interbreed to produce fertile offspring
What are biotic factors?
the living aspects of the environment
e.g. other organisms (same/diff. species)
What are abiotic factors?
the non-living aspects of the environment
e.g. sunlight
soil
water
temp.
What is a niche?
refers to the ROLE of a SPECIES in its ECOSYSTEM
therefore, includes how species interacts with abiotic factors
What are the 2 important aspects of a species’ niche?
- food it eats
2. food it obtains
What is the competitive exclusion principle?
Two diff. species cannot occupy the same niche in the same place, at the same time
elaborate
What are the different modes of nutrition?
autotrophy
- photoautotroph - chemoautotroph
heterotrophy
- consumers - detritivores - saprotrophs
What does the mode of nutrition autotrophy mean?
self-feeding
organisms synthesise organic molecules from inorganic sources
What does the mode of nutrition photoautotroph mean?
photosynthesis
makes organic compounds using energy derived from the sun
What does the mode of nutrition chemoautotroph mean?
chemosynthesis
makes organic compounds using energy derived from the oxidation of chemicals
What does the mode of nutrition consumer mean?
an animal that feeds on living or recently killed organisms via ingestion
herbivore omnivore carnivore
What is the role of decomposers (detritivores & saprotrophs)?
unlock stored nutrients in plants & animals
break down body of dead organisms
convert organic matter into usable form for other organisms
recycle nutrients, therefore, major role in formation of soil
What are detritivores?
type of heterotroph that obtains nutrients from non-living organic sources via internal digestion (e.g. humus & detritus)
e.g. dung beetles, earthworms, woodlice, snails, crabs
What are saprotrophs?
type of heterotroph that live in or on non-living organic matter, secrete digestive enzymes into it and absorbs the products of digestion externally
e.g. bacteria, fungi, mold
What is a food chain?
shows the flow of energy through the trophic levels of a feeding relationship
linear flow
3-5 organisms
What is a trophic level?
feeding position of an organism in food chain
e.g. producer
primary consumer
secondary consumer
tertiary consumer
How can species interact in an ecosystem?
competition
- interspecific - intraspecific
predator-prey
herbivore - plant
symbiotic:
parasitism
mutualism
commensalism
What is interspecific competition?
competition btw members of DIFFERENT species for the SAME RESOURCE
What is intraspecific competition?
competition for RESOURCES btw member of the SAME species
What is the predator-prey relationship?
one species kills and eats another species
predator does killing and eating
prey = food source
What is the herbivore-plant relationship?
plants cannot run away form herbivores
therefore, some protect themselves wt physical structures (e.g. thorns, spines, stinging hairs) others use chemicals
What are symbiotic relationships?
symbiotic relationships are those in which the organisms living together depend on each other
parasitism mutualism commensalism
What is parasitism?
one species (parasite) benefits while the other (host) is harmed
e.g. tick & human
What is mutualism?
both species that are interacting wt each other benefit
e.g. flower & bee
leopard shark and remora fish
What is commensalism?
one species benefits while the other is unaffected
e.g. deer and birds
