How many of the following statements concerning the loss of hind limbs during whale evolution are true? 1. it is well documented by a series of transitional fossils. 2. it explains why modern whales have vestigial pelvic girdles. 3. it involved changes in the sequence or expression of hox genes. 4. it is an example of macroevolution. 5. it, and the loss of limbs by snakes, are an example of similar adaptations to a similar environment. a) only one statement is true. b) two statements are true. c) three statements are true. d) four statements are true. e) all five statements are true.

Which of these is true of the cytoplasm of an unfertilized egg? a. it is an unevenly distributed mixture of mrna, proteins, organelles, and other substances. b. it does not contain substances that are important in directing development. c. these substances are supplied by the sperm. d. it does not contain substances that are important in directing development. e. development is directed solely by the surrounding cells. f. it is a homogeneous mixture of mrna, proteins, organelles, and other substances. g. it does not contain substances that are important in directing development. h. these substances are produced by the dna of the fertilized zygote.