Fruit-fly eyes are of the compound type, which is structurally very different from the camera-type eyes of mammals. Even the camera-type eyes of molluscs, such as octopi, are structurally quite different from those of mammals
Yet, fruit flies, octopi, and mammals possess very similar versions of Pax-6. The fact that the same gene helps produce very different types of eyes is most likely due to _____. A) the few differences in nucleotide sequence among the Pax-6 genes of these organisms
B) variations in the number of Pax-6 genes among these organisms
C) the independent evolution of this gene at many different times during animal evolution
D) differences in the control of Pax-6 expression among these organisms
D
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Which of the following is sometimes useful against viral infections?
A. Zidovudine B. Rifampin C. Trimethoprim D. Streptomycin
A triglyceride molecule is made up of ____
a. one glycerol and two fatty acids b. two fatty acids and two glycerols
c. one fatty acid and three glycerols d. one glycerol and three fatty acids e. one glycerol and two fatty acids
What factor do the diseases PKU, albinism, and alkaptonuria all have in common?
What will be an ideal response?
A friend makes the argument that transgenic crops have only been used to enrich large corporations, not to improve people's health. What is the best counterexample?
A. Bt maize B. Cre-Lox C. glyphosate-resistant soybeans D. Golden rice