Biological Diversity Flashcards
Taxonomy/classification
Naming and classification of species
System of binomial nomenclature
● Two-part name for every organism
● Hierarchical classification of species into broader groups of organisms
Taxa
The broader groups of taxa
Three-domain system
Organized organisms into three domains: Bacteria, Archaea, and Eukarya
Domain Bacteria
● All are single-celled prokaryotes with no internal membranes
● Some are anaerobes, some are aerobes
● Bacteria play a vital role in the ecosystem as decomposers that recycle dad organic matter
● Many are pathogens, causing disease
● Bacteria play a vital role in genetic engineering (E. coli)
● Some bacteria carry out conjugation, a primitive form of sexual reproduction where individuals exchange genetic material
● Some carry out photosynthesis, bt others do not
● Viruses are placed here
Domain Archaea
● Unicellular
● prokaryotic–ni internal membranes
● Includes extremophiles, organisms that live in extreme environments
Methanogens
● Belong to Domain Archaea
● Obtain eneergy in a unique way by producing methane from hydrogen
Halophiles
● Belong to Domain Archaea
● Thrive in environemnts with high salt concerntrations
Thermophiles
● Belong to Domain Archae
● Thrive in very high temperatures
Domain Eukarya
● Includes four of the original kingdoms: protista, fungi, plantae, and animalia
● All organisms have a nucleus and internal organelles
Systematics
● Replaced taxonomy
● Includes taxonomy but considers biological diversity in an evolutionary context
● Focuses on tracing the ancestry of organisms
Kingdom Protista
● Includes the widest variety of organisms, but all are eukaryotes
● Includs organisms that do not fit into the fungi or plant kingdoms
● Consists of single and primitive multicelled organisms
● Includs heterotrophs and autotrophs
● Protozoans are classified by how they move: pseudopods, cilia, flagella
● Some carry out conjugation
● Some cause serious diseases
Kingdom Fungi
● All are heterotrophs and eukaryotes
● Secrete hydrolytic enzymes outsid the body where extracellular digestion occurs, then the building blocks of the nutrients are absorbed intot he body of the fingus by diffusion
● Are important in the ecosystem as decomposers
● Cell walls are composed of chitin, not cellulose
Kingdom Plantae
● All are autotrophic eukaryotes
● Some plants hae vascular tissue, some do not
Kingdom Animalia
● All are heterotrophic, multicellualr eukaryotes
● Are grouped in 35 phyla, 9 main ones are Porifera, Cnidaria, Platyhelminthes, Nematoda, Annelida, Mollusca, Arthropoda, Echinodermata, and Chordata
● Most animals reproduce sexually with a dominant diploid stage
● In most species, a small, flagellated sperm fertilizes a larger, nonmotile egg
● Monophyletic–all animal lineages can be traced back to one common ancestor
● Classified by anatomical features, DNA data, and embryonic dvelopment
Cell
Basic unit of all forms of life