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23 terms

IB Ecology

STUDY
PLAY
ECOLOGY
The study of relationships between organisms and between organisms and their environment
HABITAT
The environment in which a species normally lives
SPECIES
A group of organisms with similar characteristics, which can interbreed and produce fertile offspring.
POPULATION
A group of organisms of the same species, who live in the same area at the same time.
COMMUNITY
A group of populations living together and interacting with each other in an area
ECOSYSTEM
A community and its abiotic environment
NATALITY
Birth
MORTALITY
Death
IMMIGRATION
Organisms move into an area from elsewhere
EMIGRATION
Organisms move out of the area to live elsewhere
CARRYING CAPACITY
The maximum population size that can be supported by the environment
AUTOTROPH
An organism that can synthesise its own organic molecules from simple inorganic substances (all plants)
HETEROTROPH
An organism that obtains organic molecules from other organisms ( fungi, animals)
CONSUMER
An organism that ingests organic matter that is living or recently killed (lion)
DETRITOVORE
An organism that ingests dead organic matter (earthworm, dung beetles)
SAPROTROPH
An organism that lives on or in dead organic matter, secreting enzymes into it and absorbing the products of digestion (bacteria and fungi)
TROPHIC LEVEL
The position of an organism in the food chain
PORIFERA
No clear symmetry, attached to a surface, pores through body, no mouth or anus. sponges.
CNIDARIA
radially symmetric, tentacles, stinging cells, mouth but no anus. jellyfish, corals, sea anemones
PLATYHELMINTHS
Bilaterally symmetric, unsegmented, flat bodies, mouth but no anus. planaria, tapeworms, liverflukes.
ANNELIDA
Bilaterally symmetric, segmented, bristles often present, mouth and anus. earthworms, leeches, ragworms.
MOLLUSCA
muscular foot and mantle, usually shell, segmentation not visible, mouth and anus. slugs, snails, clams, squids.
ARTHROPODA
bilaterally symmetric, exoskeleton, jointed appendages, segmented. insects, spiders, crabs, millipedes.