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Let P = purple flowers and p = white, and T = tall plants and t = dwarf. Of the 16 possible gamete combinations in the dihybrid cross between 2 double heterozygotes, how many would produce the phenotype white, tall?

_______________________ epithelium provides a moist and slippery surface and is well suited to resist stree, as in the ____________________.

The hypodermis usually has an abundance of this tissue.

Write the number in standard form.

Crick and his colleagues proposed that the genetic code consists of a series of blocks of information, called ________, each corresponding to one amino acid in an encoded protein.

These cells stand guard against toxins, microbes and other pathogens.

In 1910, Morgan did a series of experiments with the fruit fly Drosophila, an organism where females are XX and males are XY. When a mutant male fly with white eyes was crossed with a wild type female with red eyes, none of the F1 progeny had white eyes but 18% of the F2 progeny had white eyes. Unexpectedly, all of these white-eyed F2 flies were males. Based on these results, Morgan concluded that white eyes is caused by a recessive X-linked allele. Suppose Morgan had found that half of the F1 progeny had white eyes but all of these white-eyed F1 flies were females. In this case, a valid hypothesis would be

32. Carrier-mediated transport is also called  

38. What initiates the sodium-potassium pump?  

Based on their experiment with T2 bacteriophages, Hershey and Chase concluded that