BJU Biology Chapters 9-10: The Classification of Organisms & Bacteria and Viruses

taxonomy

the science of classifying organisms

the seven levels of taxonomy

Kingdom, Phylum, Class, Order, Family, Genus, Species

domain

a taxonomic category above the kingdom level

Kingdom Eubacteria

kingdom of unicellular prokaryotes whose cell walls are made up of peptidoglycan

Kingdom Archaebacteria

kingdom of unicellular prokaryotic extremophiles whose cell walls do not contain peptidoglycan

Kingdom Protista

a kingdom of a variety of eukaryotic unicellular, colonial, and multicellular organisms; includes protozoans and algae

Kingdom Fungi

a kingdom of multicellular eukaryotic organisms, such as mushrooms and molds, that have a cell wall containing chitin

Kingdom Plantae

a kingdom of multicellular autotrophs with true tissues and cell walls containing cellulose

Kingdom Animalia

a kingdom of multicellular, eukaryotic organisms that are free-moving, lack cell walls, and have true tissues

binomial nomenclature

a system for giving each organism a two-word scientific name that consists of the genus name followed by the species name

species

a group of similar organisms that can breed and produce fertile offspring

speciation

formation of new species

adaptation

inherited characteristic that increases an organism's chance of survival

biblical kind

a grouping of organisms that are able to breed among themselves and produce offspring; God created "kinds" in Genesis 1

size of a bacterium compared to a human cell

one thousand times smaller

three ways that bacteria influence our lives

cause disease, are decomposers, and live in our body as a microbiome

probiotics

live microbes applied to or ingested into the body, intended to exert a beneficial effect

prokaryotic

cells that do not have a nucleus

thermoacidophiles

a group of archaebacteria that live in extremely acidic and high temperature environments

methanogens

a group of archaebacteria that produce methane as a byproduct of their metabolism; live in sewage and animal intestines

halophiles

"salt-loving" archaea that live in environments that have very high salt concentrations

coccus

a spherical bacterium

bacillus

rod-shaped bacterium

spirillum

spiral-shaped bacteria

capsule

Aasticky layer that surrounds the cell walls of some bacteria, protecting the cell surface and sometimes helping to glue the cell to surfaces

nucleoid region

a dense region of DNA in a prokaryotic cell

plasmid

small, circular piece of DNA located in the cytoplasm of many bacteria

flagella

whiplike tails found in one-celled organisms to aid in movement

binary fission

a form of asexual reproduction in single-celled organisms by which one cell divides into two cells

conjugation

in bacteria, the direct transfer of DNA between two cells that are temporarily joined

transformation

modification of a cell or bacterium by the uptake and incorporation of DNA from its environment

transduction

transfer of genetic material by a bacteriophage

autotrophic

make their own food

photosynthetic

describes bacteria that make their own food using light energy

chemosynthetic

a process whereby certain organisms obtain cellular energy from the breakdown of inorganic chemicals

heterotrophic

organisms that obtain their nutrients or food from consuming other organisms

parasitic

feeding on a living host

saprophytic

relationship in which an organism obtains its nourishment from dead organic matter

symbiotic

involving a close relationship of mutual dependence

endospore

a thick-walled protective spore that forms inside a bacterial cell and resists harsh conditions.

obligate aerobe

organism that requires a constant supply of oxygen in order to live

obligate anaerobe

organism that cannot live in the presence of oxygen

facultative anaerobe

organism that can survive with or without oxygen

ways to control the growth of bacteria in foods

canning, freezing, drying, refrigerating, salting, pickling radiation, adding chemical preservatives

antibiotic

a chemical that kills bacteria or slows their growth without harming body cells

virology

study of viruses

structure of a virus

DNA or RNA surrounded by a protein coat

bacteriophage

kind of virus that infects bacteria

superbug

a bacteria that is resistant to all antibiotics

virulence

ability to produce disease

lytic cycle

a viral reproductive cycle in which copies of a virus are made within a host cell, which then bursts open, releasing new viruses

retrovirus

an RNA virus that reproduces by transcribing its RNA into DNA and then inserting the DNA into a cellular chromosome

lysogenic cycle

a viral reproductive cycle in which the viral DNA is added to the host cell's DNA and is copied along with the host cell's DNA

transforming virus

a virus within a cell that does not kill the host cell but transforms it (ex. warts)

emerging virus

a viral illness that originated in animals but has been transferred and spread by humans