biodiversity Flashcards
species
group of organisms that can breed to produce fertile offspring
population
group of organisms of same species, living in same area at the same time
community
group of populations living and interacting with each other in an area
ecosystem
community and its abiotic environment
Binomial naming system
First name is generic name- denotes genus which organism belongs to
second name- denotes species
Names are printed in italics or if hand written underlined to indicate that they are scientific names
First letter of genus is upper case but rest of genus and all of species name is lower case
is specific name is not known can be written as sp
courtship behaviour
Courtship behaviour helps achieve mating by enabling individuals to:
1- recognise members of their own species
2- identify a mate that is capable of breeding. Both mates must be sexually mature, fertile and receptive to mating
3- form a pair bond. Lead to successful mating and raising of offspring
4- synchronise mating- takes place when maximum possibility of sperm and egg meeting
5-became able to breed by bringing member of opposite sex into correct physical state that allows breeding to occur
principles of classification
Artificial classification- divide organisms according to differences that are useful at the time eg colour, size, leaf shape etc. Described as analogous characteristics as have same function but don’t have same evolutionary origins eg wings are used for flight but originated in different ways
Phylogenetic classification- based on evolutionary relationships between organisms and their ancestors. Classifies species into groups using shared features derived from their ancestors. Arranges groups into a hierarchy in which groups are contained within larger composite groups with no overlap. Partly based on homologous characterstics. These have simmilar evolutionary origins regardless of their functions eg wing of bird, arm of human and front leg of horse
classification
grouping of organisms
taxonomy
theory and practice of biological classification
types of domains
Each group within a phylogenetic classification is called a taxon.
Domain is highest taxonomic rank. Split into
1-bacteria- have no membrane bound organelles, unicellular, 70S ribosomes (smaller), murein cell walls, single loop of DNA but no histones
2- archaea- group of single celled prokaryoes that were originally classified as bacteria. They differ from bacteria because: genes and protein synthesis more similar to eukaryotes, membranes contain fatty acid chains attached to glycerol by ETHER linkages, no murein in cell walls, have more complex form of RNA polymerase
3- eukarya
eukarya domain
Divided into 4 kindoms
protoctista
fungi
plantae
animalia
Within each kingdom largest groups are known as phyla. Organisms in each phylum have a body plan radically different from organisms in any other phylum.
Diversity within each phylum allows it to be divided into classes, then orders then families, then genera and then species
Phylogeny
Hierarchical order of taxonomic ranks based on supposed evolutionary line of descent of group members. This evolutionary relationship between organisms is known as phylogeny. Phylogeny of an organisms reflects evolutionary branch that leads up to it. Usually represented by phlogenetic tree. OLDEST species at base of tree, while more recent ones are at ends of branches
Biodiversity
variety of organisms living in an area
species diversity
number of different species and the number of individuals of each species within any one community. One way to measure may be species richness (number of different species in a particular area at a given time)
ecosystem diversity
range of different habitats from small local habitat to whole earth
