In a developing human embryo, the hands and feet resemble mittens, with cells and tissues present between the fingers and toes. When a baby is born, these cells are not present, resulting in distinct fingers and toes. In the development of fingers and toes these cells were lost by ____.
A. cell connections
B. cell migration
C. apoptosis
D. cell division
E. cell morphology
C. apoptosis
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If two otherwise dissimilar organisms share similar genomic DNA, it suggests which of the following conclusions?
A. The shared genes are ancient and probably no longer function within the altered physiological states of modern organisms. B. The shared genes have evolved a number of times and have no phylogenetic significance. C. The two taxa are more closely related than formerly believed. D. The shared genes developed early in evolution and are likely to be applicable to a wide diversity of organisms. E. DNA is not a reliable basis for phylogenetic decisions.
Erasmus Darwin, in his discussion of evolutionary possibilities, included all of the following EXCEPT
A. changes during the development of organisms. B. comparative anatomy of plants and algae. C. animal breeding by humans. D. vestigial organs.
What is the difference between standard error of the mean (SEM) and standard deviation (SD)?
A. Standard deviation tells us about how well we can trust mean from samples. B. They are the same. C. Standard error of the mean tells us about how well we can trust mean from samples. D. Standard deviation is square of Standard error of the mean.
Why is it important to compare DNA sequences in the construction of an evolutionary tree?
a. Similarities in physical appearance cannot be used to construct and evolutionary tree. b. Convergent evolution can cause distantly related organisms to appear closely related. DNA sequence analysis can show that they are actually distantly related. c. DNA sequence comparison is not required; homologous features alone are sufficient in evolutionary tree construction. d. RNA sequences are actually more important in constructing an evolutionary tree since they are the precursors to DNA. e. None of the above