Which of the following represents the strongest evidence that two of the three middle ear bones of mammals are homologous to certain reptilian jawbones?
A) They are similar in size to the reptilian jawbones.
B) They are similar in shape to the reptilian jawbones.
C) The mammalian jaw has fewer bones than does the reptilian jaw.
D) These bones can be observed to move from the evolving jaw to the evolving middle ear in mammalian embryos.
D
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Imagine that you are investigating the production of insulin in normal cells. You are using these cells to help determine the cause of faulty insulin production in other cells where insulin appears to be synthesized but fails to be secreted from the cell
You design experiments using three different pharmaceutical compounds to help pinpoint the trouble spot in the protein synthetic pathway. The first compound blocks transport vesicle movement in the cytoplasm. The second blocks the SRP release from the ribosome and mRNA. The third compound binds to and blocks the signal sequence so the SRP cannot recognize it. Which of the following describes what you would expect to observe in cells treated with the inhibitor of transport vesicle movement? A. an accumulation of insulin in the cytosol B. an accumulation of insulin in the Golgi C. an accumulation of insulin at the plasma membrane D. a lack of insulin in the cell
An assumption of twin studies is that
A) twins are more intelligent than singletons. B) both twins of a pair have had similar experiences. C) the twins are monozygotic. D) he twins are dizygotic.
A frontal plane is indicated by
a. A. b. B. c. C. d. D. e. E.
Before contact with Europeans, a tiny, isolated group of South Pacific islands had a population of about 50,000 people. Because of poor management of their own resources, the population fell to around 5000 by about the year 1750. When Europeans finally
arrived, they brought smallpox, and after the ensuing epidemic, only about 800 islanders were left alive. The unusual genetic makeup of the native population is due to what phenomenon? A) speciation B) gene flow C) genetic drift D) bottleneck effect