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BIOL 112 EXAM 1 (TAMU TAG) Actual
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Lamarck's ideas about_____ have been soundly rejected. - ✔✔How adaptation occurs Darwin's mechanism for the cause of evolution was based upon... - ✔✔Characteristics that enhance survival are heritable &Existing variation among individuals What accounts for broad, continuous variation of a particular phenotype within a population. - ✔✔Multiple genes Select the true statement from those listed below. The evolution of larger genome size is expanded by gene duplication events When a point mutation occurs in the DNA of reproductive cells, a new allele is always formed Most phenotypic variation within populations is due to environmental effects All of the above are TRUE - ✔✔The evolution of larger genome size is expanded by gene duplication events In a population of mice under Hardy-Weinberg conditions, black coat color is completely dominant to brown coat color. Only 4% of the population have brown coats. What proportion of the population is heterozygous? - ✔✔0.32 = 32% Natural selection acts directly on the _________ but the fundamental unit of evolution is the _________.
- ✔✔Individual; population A large population of birds contains 16% homozygous recessive for small beaks (large beak size is completely dominant). Assume random mating and H-W equilibrium the next generation will contain: - ✔✔16% birds with small beaks
84% birds with large beaks In the study of mosquitofish in the Bahamas, body shape in different populations was influenced by the presence or absence of predators. The fact that the fish preferred to mate with other fish that had the same body shape was interpreted as evidence for? - ✔✔The process of allopatric speciation In an example covered in class and in your textbook, a study of soapberry bugs in Florida showed that populations feeding on fruits of the recently introduced raintrees had a shorter feeding beaks than the populations feeding on the native balloon vines. Researchers say that the shorted beaks are a change in the bugs due to natural selection. For this to be evidence of the process of natural selection, what must be shown to be true? - ✔✔That the length of the feeding beak is an inherited feature. Evolution is a change in a population's _____ frequency over generations. - ✔✔Allele Mendel - ✔✔established the concept of the gene as the unit of heredity Hutton and Lyell - ✔✔the great age of the Earth and the long-term action of continuous gradual processes producing large-scale geologic change Wallace - ✔✔independently developed a theory of natural selection; provided incentive for Darwin to get his work published Darwin - ✔✔natural selection as the mechanism by which organisms become adapted to their environment Linnaeus - ✔✔established the binomial system of biological nomenclature Lamarck - ✔✔The more a structure is used in an individual, the more developed it becomes; the character changes acquired during the life of the individual are then passed to offspring
The Pingelapese people of the East Caroline Islands are descended from 20 survivors of a typhoon and subsequent famine in 1775. Among the survivors was an individual heterozygous for a recessive mutation that causes achromatopsia, a condition that causes color-blindness, extreme sensitivity to light, and poor visual acuity. Although this condition is usually very rare, affecting about 1 person in 20,000, about 20% of today's 3000 Pingelapese are achromats. The most likely explanation for the plight of the Pingelapese is... - ✔✔Bottle neck effect If a new species of plant is to be produced by means of allopolyploidy from two parental species that are 2n = 6 and 2n = 8, how many chromosomes would you expect in the somatic cells of the new species? - ✔✔ 14 What is necessary for allopatric speciation? - ✔✔Geographic isolation In which of the following pairs of populations is allopatric speciation mist likely to occur? - ✔✔Pine trees in Alaska and pine trees on the island of Madagascar Approximately 1 out of every 2,500 Caucasians in the United States is born with the recessive disease cystic fibrosis. According to the Hardy-Weinberg equilibrium equation, approximately what percentage of people are carriers? - ✔✔4% Hypothetical scenario: the greater prairie chicken populations in Kansas are reduced from the current 750,000 to 200 in two decades as natural prairie is converted into suburban zones. Which of the following is the best prediction about the remaining population 100 years later? - ✔✔It will have much less genetic diversity Arrange in order of appearance, from earliest to most recent. cyanobacteria, multicellular organisms, prokaryotes, eukaryotes - ✔✔1.Prokaryotes, 2. cyanobacteria, 3. eukaryotes, 4. multicellular organisms Acheta veletis and A.pennsylvanicus are crickets which are sympatric over much of eastern North America. There is no evidence that these species utilize different natural resources and each has a single annual generation. The adults of A. veletis are present in early summer (April to July) and the adults of A. pennsylvanicus are present in late summer (mid July to October). The factor that maintains these forms as species is: - ✔✔Temporal isolation
In Drosophila, successful mating is frequently dependent upon an elaborate courtship "dance" performed by the male. Over 200 species of these fruit flies occur on the Hawaiian Islands. However, mating between many of these species is avoided, as the females only respond to the particular "dance" of conspecific males. This is an example of? - ✔✔Behavioral isolation On the Star Wars planet of Kashyyyk, 1 out of every 1,211 Wookiee is born with a recessive mystery disease. According to the Hardy-Weinberg equilibrium equation, what is the approximate frequency of Wookiees that are carriers? State your answer as a decimal to two places. - ✔✔0.06 or 6% Mutations in what class of genes have probably been responsible for many of the changes leading to the great diversity of life existing today? - ✔✔Developmental genes Several species of fish in the genus Astyanax occur only in the waters in completely dark underground caves. These blind cave fish have no external eyes, but have very tiny and functionless eyes under the skin. Genetic studies clearly indicate that the blind cave fish are evolved from surface-dwelling species with typical and functional eyes. The eyes of these blind cave fish are, therefore, an example of - ✔✔A vestigial structure In a population of 500 snarks, 300 individuals are homozygous dominant at the purple-spotted locus (SS), 150 are heterozygous (Ss), and 50 have no spots (ss). Determine the allelic frequencies. - ✔✔p= 0.75 q=
Hyla versicolor and H. chrysoscelis are frogs which are morphologically indistinguishable, non-hybridizing and broadly sympatric in central Texas. There is no evidence that these species utilize different natural resources and both reproduce throughout the spring and summer. Mating involves males clutching the females but fertilization is external. These species are easily distinguished by their mating calls; males and females of H. versicolor are "slow trilling" whereas males and females of H. chrysoscelis are "fast- trilling." The factor that most likely maintains these forms as species is - ✔✔behavioral isolation A population of 500 lizards vary in the color of their stripes, controlled by a single autosomal gene. The allele Y has incomplete dominance over the allele y. Lizards with YYhave bright yellow stripes. Lizards with Yy have faded yellow stripes and lizards with yy have white stripes. A survey of the population yielded this data: bright-yellow striped: 300 lizards faded-yellow striped: 100 lizards
