VISUAL SKILLS The relative lengths of the frog and mouse branches in the phylogenetic tree in Figure 26.13 indicate that a. frogs evolved before mice. b. mice evolved before frogs.c. the homolog has evolved more rapidly in mice.d. the homolog has evolved more slowly in mice.

VISUAL SKILLS Based on the tree below, which statement is not correct?

a.Goats and humans form a sister group.b. Salamanders are a sister group to the group containing lizards, goats, and humans.c. Salamanders are as closely related to goats as to humans.d. Lizards are more closely related to salamanders than to humans.

If you were using cladistics to build a phylogenetic tree of cats, which of the following would be the best outgroup?a. wolfb. domestic catc. liond. leopard

You can use a 'one-snip test' to identify monophyletic groups—meaning that if you 'cut' any branch on a tree, everything that 'falls off' is a monophyletic group. Why is this valid?

In terms of structure, how do channel proteins differ from carrier proteins?

If you were using cladistics to build a phylogenetic tree of cats, which would be the best choice for an outgroup?a. kangaroob. leopardc. domestic catd. iguana

Use the fossil evidence shown in Figure 25.6 to determine whether flight evolved earlier in insects or in birds. Is flight an example of homology or convergent evolution? Explain.

Which of the following could provide the best data for determining the phylogeny of very closely related species?a. the fossil recordb. their morphological differences and similaritiesc. a comparison of nucleotide sequences in homologous genes and mitochondrial DNAd. a comparison of their ribosomal DNA sequences

You have discovered an enzyme that appears to function only when a particular sugar accumulates. Which of the following scenarios would you predict to be responsible for activating this enzyme?a. The sugar cleaves the enzyme to form the active conformation.b. The sugar is an allosteric regulatory molecule for the enzyme.c. The sugar is a competitive inhibitor for the enzyme.d. The sugar phosphorylates the enzyme to form the active conformation