Which of the following observations helped Darwin shape his concept of descent with modification?a. Species diversity declines farther from the equator.b. Fewer species live on islands than on the nearest continents.c. Birds live on islands located farther from the mainland than the birds' maximum nonstop flight distance.d. South American temperate plants are more similar to the tropical plants of South America than to the temperate plants of Europe.

True or false? Some traits are considered vestigial because they existed long ago.

What types of drugs have helped reduce the death rate due to tuberculosis infection, and why have they become less effective more recently?

What are three ways monosaccharides differ from one another?

Define artificial selection, and compare and contrast it with natural selection.

Complete this concept map describing potential causes of evolutionary change within populations. a.b. c. d. e. f. g.

What type of bond is formed between two sugars in a disaccharide?a. glycosidic linkageb. phosphodiester bondc. peptide bondd. hydrogen bond

Which of the following observations is not part of the theory of natural selection?a. Populations of organisms have more offspring than will survive;b. There is variation among individuals in a population;c. Modern organisms are unrelated;d. Traits can be passed on from parent to offspring;e. Some variants in a population have a higher proba­bility of survival and reproduction than other variants do.

Within six months of effectively using methicillin to treat S. aureus infections in a community, all new S. aureus infections were caused by MRSA. How can this best be explained?a. A patient must have become infected with MRSA from another community.b. In response to the drug, S. aureus began making drug- resistant versions of the protein targeted by the drug.c. Some drug-resistant bacteria were present at the start of treatment, and natural selection increased their frequency.d. S. aureus evolved to resist vaccines.