The protostome developmental sequence arose just once in evolutionary history, resulting in two main subgroups—Lophotrochozoa and Ecdysozoa. What does this finding suggest?
A) These two subgroups have a common ancestor that was a deuterostome.
B) The protostomes are a polyphyletic group.
C) Division of these two groups occurred after the protostome developmental sequence appeared.
D) The lophotrochozoans are monophyletic.
Answer: C
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A diagnostic sign of typical pneumonia is consolidation which
A) is a granuloma walling off infected phagocytes in the lungs and appears as a clear region on a chest X-ray. B) is a granuloma walling off infected phagocytes in the lungs. C) is fluid rather than air in the alveoli. D) appears as a clear region on a chest X-ray. E) is fluid rather than air in the alveoli and appears as a clear region on a chest X-ray.
The term oxidation is derived from the name of the element oxygen. This is reasonable, because oxygen
A. attracts electrons very strongly. B. can be oxidized by accepting electrons. C. contains more electrons than are needed. D. passes electrons to many other types of molecules.
The enzyme responsible for breaking down
alcohol is a. alcohol methylase. b. alcohol polyphosphorylase. c. hydroxyl alcoholgenase. d. transmethylogenase. e. alcohol dehydrogenase
If a cell has a diploid number, it indicates that _____
A) each chromosome belongs to a homologous pair B) it is a germ cell: an egg or sperm C) the cell was produced by a meiotic nuclear division D) cytoplasmic division failed and the cell has become multinucleated