Exam Revision notes for Grade Eleven Biology

Natural changes
Primary succession:
·Occurs when living things colonise new land such as in a volcanic eruption
·Bacteria and lichens are normally the first organisms that can live on bare rock
·As organisms progressively colonise an area, they change the environment, thus making it suitable for new species
·Sometimes when organisms change an environment, it is no longer suitable for themselves
·The changing environment leads to a change in species, which is in essence, what a succession is.
Secondary succession:
·Occurs in an already established ecosystem
·These successions are often caused by natural disasters like floods or fires
·Although they do not involve a total change in species they often involve a marked change ad new species take hold in the affected area.
CLASSIFICATION
Taxonomy:
·Kingdom
·Phylum
·Class
·Order
·Family
·Genus
·Species
Scientific names:
·Binomial system uses GENUS and SPECIES names.
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