TOEFL : Essential information
Study concepts, example questions & explanations for TOEFL
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Example Question #1 : Essential Information
Adapted from "Taking a Second Look: An Analysis of Genetic Markers in Species Relatedness" by Joseph Ritchie (2014)
Phylogenetics is the study of genetic composition in various species and is used by evolutionary biologists to investigate similarities in the molecular sequences of proteins in varying organisms. The amino acid sequences that build proteins are used to construct mathematical matrices that aid in determining evolutionary ties through the investigation of percentage similarities. The study of these matrices helps to expose evolutionary relationships between species that may not have the same overt characteristics.
Species adapt and evolve based on the pressures that exist in their environment. Climate, food source, and habitat availability are only a few factors that act on species adaptation. These stressors can alter the physical characteristics of organisms. This divergence in evolution has made it difficult to determine the interrelatedness of organisms by analyzing their physical characteristics alone.
For instance, looking only at physical characteristics, the ghost bat resembles a pigeon more than a spider monkey; however, phylogenetics has found that the amino acid sequences that construct the beta hemoglobin molecules of bats are twenty percent more similar to those of mammalian primates than those of birds. This helps reject the assumption that common physical characteristics between species are all that is needed to determine relatedness.
The differences produced by divergent evolution observed in the forest-dwelling, arboreal spider monkey and the nocturnal, airborne ghost bat can be reconciled through homology. Homologous characteristics are anatomical traits that are similar in two or more different species. For instance, the bone structure of a spider monkey’s wrist and fingers greatly resembles that of a bat’s wing or even a whale’s fin. These similarities are reinforced by phylogenetic evidence that supports the idea that physically dissimilar species can be evolutionarily related through anatomical and genetic similarities.
According to the passage, which of the following is an environmental pressure that can result in species adaptation and evolution?
Physical characteristics
Climate
Competition
Adaptability
Climate
"Climate" is the only answer choice supported by the passage. The passage states that "climate," "food source," and "habitat availability" are environmental pressures that may cause adaptations. The choice "physical characteristics" is incorrect because they change as a result to these pressures.
Example Question #1 : Essential Information
The following is an excerpt from Pride and Prejudice by Jane Austen (1813):
“Vanity and pride are different things, though the words are often used synonymously. A person may be proud without being vain. Pride relates more to our opinion of ourselves, vanity to what we would have others think of us.”
Based on the passage above, "vanity" may most closely be understood to mean __________.
a concern for how others perceive themselves
a high opinion of others
a concern for how you perceive others
a high opinion of oneself
a concern for how others perceive you
a concern for how others perceive you
The passage states that vanity has to do with what we want others to think of us. This means that it is not a self-evaluation, but a concern for how others evaluate us. Thus, it is a concern for how others perceive us.
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