Chapter 16 Flashcards
cellular slime mold
A type of protist that has unicellular amoeboid cells and aggregated reproductive bodies in its life cycle; members of amoebozoan clade.
biofilm
a surface-coating colony of prokaryotes that engage in metabolic cooperation.
autotroph
An organism that makes its own food (often by photosynthesis), thereby sustaining itself without eating other organisms or their molecules. Plants, algae, and numerous bacteria are autotrophs.
proteobacteria
A diverse clade of gram-negative bacteria that includes five subgroups known as alpha, beta, gamma, delta, and epsilon.
green alga
A member of a group of photosynthetic protists that includes chlorophytes and charophyceans, the closest living relatives of land plants. Green algae include unicellular, colonial, and multicellular species.
coccus
(plural, cocci) A spherical prokaryotic cell
secondary endosymbiosis
A process by which diversity is hypothesized to have evolved from a symbiotic association that arose when an autotrophic eukaryotic protist was engulfed by a heterotrophic eukaryotic protist.
radiolarian
A protist that moves and feeds by means of threadlike pseudopodia and has a mineralized support composed of silica.
foraminiferan (Foram)
A protist that moves and feeds by means of threadlike pseudopodia and has porous shells composed of calcium carbonate.
endotoxin
A poisonous component of the outer membrane of gram-negative bacteria that is released only when the bacteria die.
diatom
A unicellular, autotrophic protist that belongs to the stramenopile clade. Diatoms possess a unique, glassy cell wall containing silica.
peptidoglycan
A polymer of complex sugars cross-linked by short polypeptides; a material unique to bacterial cell walls.
gametophyte
The multicellular haploid form un the life cycle of organisms undergoing alternation of generations; mitotically produces haploid gametes that unit and grow into the sporophyte generation.
spirochete
A member of a group of helical bacteria that spiral through the environment by means of rotating, internal filaments.
photoautotroph
an organism that obtains energy from sunlight and carbon from CO2 by photosynthesis.
methanogen
A type of Archaea that produces methane as a metabolic waste product.
extreme halophile
A microorganism that lives in a highly saline environment, such as the Great Salt Lake or the Dead Sea.
cyanobacteria
photoautotrophic prokaryotes with plantlike, oxygen-generating photosynthesis
pathogen
An agent sucs as a virus, bacteria, or fungus, that causes disease.
pilus
(plural, pili) A short projection on the surface of a prokaryotic cell that helps the prokaryote attach to other surfaces. Specialized sex pili are used in conjugation to hold the mating cells together.
gram stain
microbiology technique to identify the cell wall composition of bacteria. Results categorize bacteria as gram-positive or gram-negative.
chlamydia
a group of bacteria that live inside eukaryotic host cells. Includes human pathogens that cause blindness and nongonococcal urethitis, a common sexually transmitted disease.
heterotroph
An organism that cannot make its own organic food molecules and must obtain them by consuming other organisms or their organic products; a consumer or a decomposer in a food chain.
archaea
One of two prokaryotic domains of life, the other being Bacteria.