Exam 25: The Origin and Diversification of Eukaryotes

Please use the following information to answer the question(s) below. Giardia intestinalis is an intestinal parasite of humans and other mammals that causes intestinal ailments in most people. It can infect people when they drink water contaminated with feces containing Giardia cysts. Upon ingestion, each cyst releases two motile cells, called trophozoites. These attach to the small intestine's lining via a ventral adhesive disk. The trophozoites anaerobically metabolize glucose from the host's intestinal contents to produce ATP. Reproduction is completely asexual, occurring by longitudinal binary fission of trophozoites, with each daughter cell receiving two haploid nuclei (n = 5). A trophozoite will often encyst as it passes into the large intestine by secreting around itself a case that is resistant to cold, heat, and dehydration. -Unlike most excavates, Giardia trophozoites have no oral groove and are unable to form food vacuoles. Thus, we should expect its nutrition (mostly glucose) to come from

Please use the following information to answer the question(s) below. Paulinella chromatophora is one of the few cercozoans that is autotrophic, carrying out aerobic photosynthesis with its two elongated "cyanelles." The cyanelles are contained within vesicles of the host cell, and each is derived from a cyanobacterium, though not the same type of cyanobacterium that gave rise to the chloroplasts of algae and plants. -Including the membrane of the surrounding vesicle, how many phospholipid (not lipopolysaccharide) bilayers should be found around each cyanelle, and which one of these bilayers should have photosystems embedded in it?

Biologists think that endosymbiosis gave rise to mitochondria before plastids partly because

Please use the following information to answer the question(s) below. Giardia intestinalis is an intestinal parasite of humans and other mammals that causes intestinal ailments in most people. It can infect people when they drink water contaminated with feces containing Giardia cysts. Upon ingestion, each cyst releases two motile cells, called trophozoites. These attach to the small intestine's lining via a ventral adhesive disk. The trophozoites anaerobically metabolize glucose from the host's intestinal contents to produce ATP. Reproduction is completely asexual, occurring by longitudinal binary fission of trophozoites, with each daughter cell receiving two haploid nuclei (n = 5). A trophozoite will often encyst as it passes into the large intestine by secreting around itself a case that is resistant to cold, heat, and dehydration. -Given its mode of reproduction and internal structures, which of the following should be expected to occur in Giardia at some stage of its life cycle? 1) separation (segregation) of daughter chromosomes 2) crossing over 3) meiosis

The best evidence for not classifying the slime molds as fungi comes from slime molds'

Green algae differ from land plants in that some green algae

Plastids that are surrounded by more than two membranes are evidence of

Please use the following information to answer the question(s) below. Paulinella chromatophora is one of the few cercozoans that is autotrophic, carrying out aerobic photosynthesis with its two elongated "cyanelles." The cyanelles are contained within vesicles of the host cell, and each is derived from a cyanobacterium, though not the same type of cyanobacterium that gave rise to the chloroplasts of algae and plants. -The closest living relative of P. chromatophora is the heterotroph P. ovalis. What type of evidence permits biologists to make this claim about relatedness?

The chloroplasts of all of the following are thought to be derived from ancestral red algae, except those of

In a synthetic biology experiment, you are given a task to design a new species of aquatic protist. Your design should account for the following characteristics: 1) The protist functions as a primary producer. 2) It cannot swim on its own. 3) It must stay in well-lit surface waters. 4) It must be resistant to physical damage from wave action. Based on these criteria, you decide to model your creation after a(n)

Which group is incorrectly paired with its description?