Bio 144 exam 2 vocab

Acidophile

organism with optimal growth pH of three or below

Alkaliphile

organism with optimal growth of nine or above

Ammonification

process by which ammonia is released during the decomposition of nitrogen-containing organic compounds

Anaerobic

refers to organisms that grow without oxygen

Anoxic

without oxygen

Antibiotic

biological substance that, in low concentration, is antagonistic to the growth of prokaryotes

Biofilm

microbial community that is held together by a gummy-textured matrix

Biological nitrogen fixation

conversion of atmospheric nitrogen into ammonia exclusively carried out by prokaryotes

Bioremediation

use of microbial metabolism to remove pollutants

Biotechnology

any technological application that uses living organisms, biological systems, or their derivatives to produce or modify other products

Black Death

devastating pandemic that is believed to have been an outbreak of bubonic plague caused by the bacterium Yersinia pestis

Botulism

disease produced by the toxin of the anaerobic bacterium *Clostridium botulinum*

CA-MRSA

MRSA acquired in the community rather than in a hospital

Capsule

external structure that enables a prokaryote to attach to surfaces and protects it from dehydration

Chemotroph

organism that obtains energy from chemical compounds

Conjugation

process by which prokaryotes move DNA from one individual to another using a pilus

Cyanobacteria

bacteria that evolved from early phototrophs and oxygenated the atmosphere; also known as blue-green algae

Decomposer

organism that carries out the decomposition of dead organisms

Denitrification

transformation of nitrate from soil to gaseous nitrogen compounds such as N2O, NO, N2

Emerging disease

disease making an initial appearance in a population or that is increasing in incidence or geographic range

Endemic disease

disease that is constantly present, usually at low incidence, in a population

Epidemic

disease that occurs in an unusually high number of individuals in a population at the same time

Extremophile

organism that grows under extreme or harsh conditions

Foodborne disease

any illness resulting from the consumption of contaminated food, or the pathogenic bacteria, viruses, or other parasites that contaminate food

Gram negative

bacterium whose cell wall contains little peptidoglycan but has an outer membrane

Gram positive

bacterium that contains mainly peptidoglycan in its cell walls

Halophile

organism that require a salt concentration of at least 0.2 M

Hydrothermal vent

fissure in Earth’s surface that releases geothermally heated water

Hyperthermophile

organism that grows at temperatures between 80–122 °C

Microbial mat

multi-layered sheet of prokaryotes that may include bacteria and archaea

MRSA

very dangerous *Staphylococcus* *aureus strain resistant to multiple antibiotics*

Nitrification

conversion of ammonium into nitrate and nitrate into soils

Nitrogen fixation

process by which gaseous nitrogen is transformed, or “fixed” into more readily available forms such as ammonia

Nodule

novel structure on the roots of certain plants (legumes) that results from the symbiotic interaction between the plant and soil bacteria, and is the site of nitrogen fixation

Nutrient

essential substances for growth, such as carbon and nitrogen

Osmophile

organism that grows in a higher sugar concentration

Pandemic

widespread, usually worldwide, epidemic disease

Peptidoglycan

material composed of polysaccharide chains cross-linked to unusual peptides

Phototroph

organism that is able to make its own food by converting solar energy to chemical energy

Pilus

surface appendage of some prokaryotes used for attachment to surfaces including other prokaryotes

Pseudopeptidoglycan

component of archaea cell walls that is similar to peptidoglycan in morphology but contains different sugars

Psychrophile

organism that grows at temperatures of -15 °C or lower

Radioresistant

organism that grows in high levels of radiation

resuscitation

process by which prokaryotes that are in the VBNC state return to viability

S-layer

surface-layer protein present on the outside of cell walls of archaea and bacteria

Serotype

strain of bacterium that carries a set of similar antigens on its cell surface, often many in bacterial species

Stromatolite

layered sedimentary structure formed by precipitation of minerals by prokaryotes in microbial mats

Teichoic acid

polymer associated with the cell wall of Gram-positive bacteria

Thermophile

organism that lives at temperatures between 60–80 °C

Transduction

process by which a bacteriophage moves DNA from one prokaryote to another

Transformation

process by which a prokaryote takes in DNA found in its environment that is shed by other prokaryotes

Viable-but-non-culturable (VBNC) state

survival mechanism of bacteria facing environmental stress conditions

Zoonosis

disease that primarily infects animals that is transmitted to humans

Biological carbon pump

process by which inorganic carbon is fixed by photosynthetic species that then die and fall to the sea floor where they cannot be reached by saprobes and their carbon dioxide consumption cannot be returned to the atmosphere

Bioluminescence

generation and emission of light by an organism, as in dinoflagellates

Contractile vacuole

vesicle that fills with water (as it enters the cell by osmosis) and then contracts to squeeze water from the cell; an osmoregulatory vesicle

Cytoplasmic streaming

movement of cytoplasm into an extended pseudopod such that the entire cell is transported to the site of the pseudopod

Endosymbiosis

engulfment of one cell within another such that the engulfed cell survives, and both cells benefit; the process responsible for the evolution of the mitochondria and chloroplasts in eukaryotes

Endosymbiotic theory

theory that states that eukaryotes may have been a product of one cell engulfing another, one living within another, and evolving over time until the separate cells were no longer recognizable as such

Hydrogenosome

organelle carried by parabasalids (Excavata) that functions anaerobically and outputs hydrogen gas as a byproduct; likely evolved from mitochondria

Kinetoplast

mass of DNA carried within the single, oversized mitochondrion, characteristic of kinetoplastids (phylum: Euglenozoa)

Mitosome

nonfunctional organelle carried in the cells of diplomonads (excavata) that likely evolved from a mitochondrion

Mixotroph

organism that can obtain nutrition by autotrophic or heterotrophic means, usually facultatively

Pellicle

outer cell covering composed of interlocking protein strips that function like a flexible coat of armor, preventing cells from being torn or pierced without compromising their ranger of motion

Phagolysosome

cellular body formed by the union of a phagosome containing the ingested particle with a lysosome that contains hydrolytic enzymes

Plankton

diverse group of mostly microscopic organisms that drift in marine and freshwater systems and serve as a food source for larger aquatic organisms

Plastid

one of a group related organelles in plant cells that are involved in the storage of starches, fats, proteins, and pigments

Raphe

slit in the silica shell of diatoms through which the protist secretes a stream of mucopolysaccharides for locomotion and attachment to substrates

Test

porous shell of a foram that is built from various organic materials and typically hardened with calcium carbonate

Arbuscular mycorrhiza

mycorrhizal association in which the fungal hyphae enter the root cells and form extensive networks

Arbuscular mycorrhizae

mycorrhizae commonly involving Glomeromycetes in which fungal hyphae penetrate the cell walls of the plant root cells (but not the cell membranes)

Ascocarp

fruiting body of ascomycetes

Ascomycota

(also, sac fungi) phylum of fungi that store spores in a sac called ascus

Basidiocarp

fruiting body that protrudes from the group and bears the basidia

Basidiomycota

(also, club fungi) phylum of fungi that produce club-shaped structures (basidia) that contain spores

Basidium

club-shaped fruiting body of basidiomycetes

Chytridiomycota

(also, Chytrids) primitive phylum of fungi that in water and produce gametes with flagella

Coenocytic hypha

single hypha that lacks septa and contains many nuclei

Commensalism

symbiotic relationship in which one member benefits while the other member is not affected

Deuteromtcota

former form phylum of fungi that do not have a known sexual reproductive cycle (presently members of two phyla: Ascomycota and Basidiomycota)

Ectomycorrhiza

mycorrhizal fungi that surround the roots with a mantle and have a Hartig net that extends into the roots between cells

Ectomycorrhizae

mycorrhizae in which the fungal hyphae do not penetrate the root cells of the plant

Facultative anaerobes

organisms that can perform aerobic and anaerobic respiration and can survive in oxygen-rich and oxygen-poor environment

Glomeromycota

phylum of fungi that form symbiotic relationships with the roots of trees

Haustoria

modified hyphae on many parasitic fungi that penetrate the tissues of their hosts, release digestive enzymes, and/or absorb nutrients from the host

Heterothallic

describes when only one mating type is present in an individual mycelium

Homothallic

describes when both mating types are present in mycelium

Hypha

fungal filament composed of one or more cells

Karyogamy

fusion of nuclei

Lichen

close association of a fungus with a photosynthetic alga or bacterium that benefits both partners

Mold

tangle of visible mycelia with a fuzzy appearance

Mycelium

mass of fungal hyphae

Mycetismus

ingestion of toxins in poisonous mushrooms

Mycology

scientific study of fungi

Mycorrhizae

a mutualistic relationship between a plant and a fungus. Mycorrhizae are connections between fungal hyphae, which provide soil minerals to the plant, and plant roots, which provide carbohydrates to the fungus

Mycosis

fungal infection

mycotoxicosis

poisoning by a fungal toxin released in food

Obligate aerobes

organisms, such as humans, that must perform aerobic respiration to survive

Obligate anaerobes

organisms that only perform anaerobic respiration and often cannot survive in the presence of oxygen

Parasitism

symbiotic relationship in which one member of the association benefits at the expense of the other