bio 2

Which of the following best explains the difference between Lamarck's and Darwin's mechanisms for evolution?

Darwin's theory corroborates with current knowledge of inherited traits.

You overhear a couple of your friends discussing the layers in sedimentary rock. One of them states that the layers only form after a large flood or earthquake. The other person agrees and adds that they must form pretty suddenly. Which of the following questions would help the least in guiding them to other causes of sedimentary rock layer formation?

Do volcanoes suddenly erupt?

How can genetic variation at the whole gene level (gene variability) be quantified?

by the average percentage of loci that are heterozygous

Two plant species live in the same biome but on different continents. Although the two species are not at all closely related, they may appear quite similar as a result of

convergent evolution.

Two species of frogs belonging to the same genus occasionally mate, but the offspring fail to develop and hatch. What is the mechanism for keeping the two frog species separate?

the postzygotic barrier, reduced hybrid viability

In peas, a gene controls flower color such that R = purple and r = white. In an isolated pea patch, there are 36 purple-flowering plants and 64 white-flowering plants. Assuming Hardy-Weinberg equilibrium, what is the value of q for this population?

0.80

If, on average, 46% of the loci in a species' gene pool are heterozygous, then the average homozygosity of the species should be

54%.

Which statement about variation is true?

All new alleles are the result of nucleotide variability.

During a study session about evolution, one of your fellow students remarks, "The giraffe stretched its neck while reaching for higher leaves; its offspring inherited longer necks as a result." Which statement is most likely to be helpful in correcting this student's misconception?

Characteristics acquired during an organism's life are not passed on through genes.

What was the prevailing belief prior to the time of Lyell and Darwin?

Earth is a few thousand years old, and populations are unchanging.

What is an example of what happens when herbivores switch to a new food source with different characteristics?

In populations that feed on goldenrain tree, natural selection results in beaks that are shorter than those in populations that feed on balloon vine.

Logically, which of the following should cast the most doubt on the relationships depicted by an evolutionary tree?

Relationships between DNA sequences among the species did not match relationships between skeletal patterns.

) Imagine you predict a particular frequency for a genotype, based upon detailed knowledge of that genotype frequency in population "X" of a species. Then, using the Hardy-Weinberg model, you find that the observed genotype frequency in a different population, named "Y" of the same species, is not significantly different from what you predicted/expected based on population "X." Which of the following should you conclude?

The particular gene of interest is not undergoing any mechanisms of evolution.

In addition to naming species, Linnaeus also grouped species into a hierarchy of increasingly inclusive categories. The largest category that would include closely related species is the

domain

Convergent evolution uses analogous features to describe

features that share common ancestry but not necessarily similar functions.

Both ancestral birds and ancestral mammals shared a common ancestor that was terrestrial. Today, penguins (which are birds) and seals (which are mammals) have forelimbs adapted for swimming. What term best describes the relationship of the bones in the forelimbs of penguins and seals, and what term best describes the flippers of penguins and seals?

homologous; analogous

The common ancestors of birds and mammals were very early (stem) reptiles, which almost certainly possessed three-chambered hearts (two atria, one ventricle). Birds and mammals, however, are alike in having four-chambered hearts (two atria, two ventricles). The four-chambered hearts of birds and mammals are best described as

homoplasies.

Which of the following reproductive types of isolation illustrates postzygotic barriers?

hybrid breakdown

What are adaptations?

inherited characteristics of organisms that enhance their survival and reproduction in specific environments

Speciation

occurs when one species splits into two or more species.

Linnaeus was a "fixist" who believed that species remained fixed in the form in which they had been created. Linnaeus would have been uncomfortable with

phylogenies.

Which of the following are problematic when the goal is to construct phylogenies that accurately reflect evolutionary history?

polyphyletic and paraphyletic taxa

he various taxonomic categories (genera, classes, etc.) of the hierarchical classification system differ from each other on the basis of

their inclusiveness.