Micro Question?

Question

The endosymbiotic theory says that precursor eucaryotic cells acquired flagella by endosymbiosis with a _____ ancestor, and others gained photosynthetic ability from endosymbiosis with a_____ ancestor.

a) protozoan, algae

b) archaea, cyanobacteria

c) spirochete, cyanobacteria

d) helminth, algae

e) none of the choices are correct

Answer 1

The answer is "c".  A spirochete is a spiral bacterium which "became" the flagellum or cilia, and cyanobacteria is a photosynthetic bacterium which "became" the chloroplast in eukaryotic cells.

BTW, the part of the theory that involves the spirochetes isn't that well accepted - the flagella don't contain their own DNA as chloroplasts and mitochondria do, so there's less supporting evidence for this.