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40 terms

Biology Ch. 15, 16

STUDY
PLAY
parsimony
quest for simplest explanation of observed phenomena
clade
group of species that includes ancestral species and all descendants
monophyletic
inclusive group of ancestros and descendants
protobiont
aggregate of abiotically produced molecules surrounded by membrane structure
ribozymes
RNA that carries out enzyme like functions
continental drift
all land on Earth was once one great mass
pangaea
plate movements brought all previously separated landmasses together into supercontinent (end of Paleozoic era)
convergent evolution
species from different evolutionary branches may come to resemble one another if the live in similar environments
analogy
similarity due to convergent evolution
pathogens
disease causing agents (bacteria)
peptidoglycan
unique material contained in bacterial cell walls
cocci
spherical prokaryotic cells
bacilli
rod-shape prokaryotes
photoautotrophs
harness sunlight for energy, use carbon dioxide for carbon
photoheterotrophs
obtain energy from sunlight, get carbon from organic sources
chemoautotrophs
harvest energy from inorganic chemicals, use carbon from carbon dioxide to make organic molecules
chemoheterotrophs
acquire both energy & carbon from organic molecules
halophiles
archaea that live in salty places
thermophiles
thrive in very hot water
methanogens
live in anaerobic environments, give off methane as waste product
proteobacteria
diverse clad of gram negative bacteria that includes five subgroups
chamydias
live inside eukaryotic host cels
spirochetes
group of helical bacteria that spiral through environment by means of rotating internal filaments
gram positive bacteria
group of bacteria with a cell wall structurally less complex, contains more peptidoglycan than that of gram negative bacteria
cyanobacteria
only prokaryotes with plant like, oxygen generating photosynthesis
exotoxins
proteins secreted by bacterial cells, include some poisons
endotoxins
components of outer membrane of gram negative bacteria, released when cell dies or digested by defensive cell
algae
autotrophic protists
protozoans
heterotrophic, eat bacteria & other protists
symbiosis
close association between organisms of two or more species
secondary endosymbiosis
process by which protist diversity hypothesized to have evolved from symbiotic association that arose when autotrophic eukaryotic protists was engulfed by heterotrophic eukaryotic protist
diplomonads
ancient heterotrophic protists
parasites
derive nutrition from living hosts
parabasalids
heterotrophic protists that have modified mitochondria that generate some energy anaerobically
euglenozoans
diverse clade of protists who share crystalline rods inside flagella
alveolates
characterized by membrane enclosed sacs beneath plasma membrane
dinoflagellates
common component of marine & freshwater phytoplankton
alternation of generations
multicellular diploid forms alternates with multicellular haploid form
gametophyte
multicellular haploid form
sporophyte
multicellular diploid form