“Killer” organisms from this genus contain Kappa particles that release a toxin fatal to organisms from this genus that lack them. For 10 points each:
[10m] Name this genus whose aurelia species is characterized by sexual reproduction. Georgy Gause formulated the competitive exclusion principle after observing these ciliates, which expel water using contractile vacuoles.
ANSWER: Paramecium [or paramecia; accept Paramecium aurelia] (The toxin is paramecin.)
[10h] Kappa particles contain these lethal protein aggregates. These aggregates form coils with a 500-nanometer diameter at neutral pH but extend into a 20-micron “javelin” in acidic environments, rupturing a predator’s vacuole.
ANSWER: R bodies [or refractile bodies; prompt on inclusions or inclusion bodies]
[10e] Kappa particles were once Caedibacter taeniospiralis (“SEE-dih-back-ter TEE-nee-oh-SPY-ruh-lis”) bacteria that underwent this process. Mitochondria and chloroplasts most likely developed from this process in which bacteria began to live inside other cells.
ANSWER: bacterial endosymbiosis [prompt on symbiosis]
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