Gaseous oxygen formed in the earth's atmosphere as a result of:
a. outgassing from the interior of the planet.
b. respiration of bacteria.
c. input from outer space.
d. photosynthesis.
D
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This unit explored features that describe living organisms. Choose all that apply to living organisms from the following.
A group is considered polyphyletic if
A. all members of the group share a common ancestor. B. not all descendants of the common ancestor are included. C. all members share homoplastic traits. D. the group does not contain the most recent common ancestor. E. it is the most parsimonious grouping.
In Figure 23-2, the taxon labeled II is:
a. monophyletic. b. paraphyletic. c. polyphyletic. d. a clade. e. an outgroup
Identify which of the following is theorized to have developed and can be explained by the endosymbiotic theory.
A) vacuoles B) Golgi apparatus C) mitochondria D) cell wall