Chapter 25 HW/Quiz

Which of the following is true of secondary endosymbiosis?

Archaeplastids, which include red and green algae and land plants, are thought to have descended from a heterotrophic protist that engulfed a(n) _____.

A sign on the beach states, "Beach Closed. Red Tide." The organisms interfering with your use of this beach are probably ___

Which of the following is a correct statement about cellular slime molds?

Why has the kingdom Protista been abandoned?

Why do some scientists believe that RNA, rather than DNA, was the first genetic material?

The oldest fossil eukaryote that can be resolved taxonomically is of

The evolution of complex multicellularity in eukaryotes

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

Select the correct statement about photosynthesis by primary producers. Cyanobacteria carry out more of the world's photosynthesis than protists do. Photosynthetic protists and prokaryotes carry out the majority of the photosynthesis in aquatic communities. Land plants carry out over 80% of the world's photosynthesis.

Which of the following statements supports the hypothesis of an endosymbiotic origin of mitochondria?

Which of the features below are found in all protist lineages?

A crucial photosynthetic gene of the cyanobacterium that gave rise to the cyanelle is called psaE. This gene is present in the nuclear genome of the cercozoan, but is not in the genome of the cyanelle. This is evidence of

In a sample of pond water, a new organism is identified with the following characteristics: It consists of 70 cells surrounded by rigid cell walls, which join the cells together. Inside each of these identical cells are mitochondria and chloroplasts. Such an organism would most likely be classified as a

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. Which of the following represents the true significance of the finding that the cyanelles of P. chromatophora stem from a different type of cyanobacterium than gave rise to chloroplasts?

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 genome of modern chloroplasts is roughly 50% of the size of the genome of the cyanobacterium from which it is thought to have been derived. In comparison, the genome of P. chromatophora's cyanelle is only slightly reduced relative to the size of the genome of the cyanobacterium from which it is thought to have been derived. What is a valid hypothesis that can be drawn from this comparison?

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

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

The chloroplasts of land plants are thought to have been derived according to which evolutionary sequence?

The evolution of multicellularity in animals has primarily occurred by the