Ch. 9 discussed nilsson-ehle's 1908 analysis of the genetics of kernel color in wheat. nilsson-ehle found that alleles at three loci (a/a, b/b, c/c) had additive genetic effects on the phenotype, with capital-letter alleles conferring red color and lower-case alleles conferring white color. suppose that genotype "aabbcc" has white kernels (call this color phenotype "0"), and that each capital-letter allele found within a genotype adds the same 1 unit of red color to the kernels. which of the possible phenotypes must have allele "b"?

b. the carbon cycle ensures living things have a source of hydrogen

the cladogram shown here shows similarities and differences among several classes of vertebrates. anatomically, the four have limb structure as their common ancestor. we might separate the mammals from the other three classes because they a) divergent; do not lay eggs b) identical; are warm-blooded c) varied; a four chambered heart d) homologous; have mammary glands

the answer is true when observing or determining population size, a direct observation is use, in which each organism is counted in a population or in an area. one benefit of this measure is that you get the exact population count but it will take a long time to  determine  the  size  of a  population.

in a chemical reaction, the atoms and molecules produced by the reaction are called products. no new atoms are created, and no atoms are destroyed. in a chemical reaction, reactants contact each other, bonds between atoms in the reactants are broken, and atoms rearrange and form new bonds to make the products.