Mating within barn swallows is non-random, as females choose mates with longer tail feathers. Which is most responsible for the less-desirable trait still existing within the population? intersexual selection adaptation heterozygosity increased fitness Question 2. 2. Which is true of both artificial selection and natural selection? Adaptation can occur within any species under any circumstance. Mutations are solely responsible for altering genetic variability and influence the direction of fitness levels. Evolution will never occur if environmental pressures continue to act. Environmental pressures change allele frequency. Question 3. 3. In a population, the allele for brown eyes (B) is dominant to the allele for blue eyes (b). The genotype frequencies for the F1 generation are shown in the table. The population is in genetic equilibrium. Allele frequency of brown and blue eyes What is the allele frequency for blue-eyed individuals in the F2 generation? 16% 30% 40% 64% Question 4. 4. What do homologous structures suggest about two species who have vastly different niches within their habitats? The same environmental factors were present during each evolutionary course. Each species experienced very little evolutionary change over time. Traits do not evolve from the genetic information passed through parental code. The two species evolved from a common ancestor. Question 5. 5. From the phylogenetic tree shown, which statement is true regarding the relationship among the species? Species A–F all evolved from species G. Species E and A evolved in similar time frames. Species G is the outlier of the group. All the species evolved in a similar time frame. Question 6. 6. What is the largest factor determining that mutations will be passed on to future generations and ensuring the increase of genetic diversity? length of chromosomes within individuals amount of crossing over that occurs during meiosis number of repeating insertions and deletions taking place during replication favorable mutations that give rise to natural selection Question 7. 7. The American buffalo experienced a near-extinction event in 1890 due to overhunting. Due to low numbers within the population, the buffalo now is experiencing a genetic bottleneck. Which is the most important factor for increasing fitness of the population for evolution? lateral gene transfer increased genetic diversity genetic engineering larger population numbers Question 8. 8. What is the strongest evidence that a common ancestor exists between all living organisms? natural selection common genetic code fossil records gene transfer Question 9. 9. Six populations belonging to the same species of song sparrows are studied within a broad geographical region. There is no apparent gene flow between the populations because of the variance in plumage, song, and color among the six populations. However, they are still able to interbreed. The birds also have significant differences in weight geographically from east to west, but only minor differences between neighboring populations. Body mass of sparrows What can be determined about possible speciation if the birds are still reproductively compatible? Genetic variation needs to be higher to shift the frequencies of alleles enough for speciation to occur. Phenotypes have no influence in determining speciation. Speciation may occur in the future. Sympatric populations are least suited for change within a short period of time. Question 10. 10. Two different but closely related orchards have red and yellow flowers. Red flowers attract more pollinators than do yellow. However, the stamens within the yellow orchards have a higher pollen count. These species have a recent common ancestor, but do not crossbreed. Evolved species How have these two species evolved within the same species? One species became extinct. Stabilizing selection acted on two gene colors within a population. Reproductive isolation occurred between phenotypes of the original species. The same pollinators coevolved with each flower type. Question 11. 11. Because guppies reach reproductive maturity 2 to 4 months after birth, they are often used in research. The graph represents a study in which guppies where placed in the same environment with two different fishes. Cichlids are known to prey on guppies while killifish are known rarely to do so. Survival of guppies among a population of killifish, cichlids, and alone What hypothesis can be formed from the graph? Mutations can change a population through the inherited traits of parental genes. Environmental pressures led to the changes in population numbers. Low genetic diversity will cause population numbers to drop across many generations. Speciation can occur within short time periods if environments are not fit for survival. Question 12. 12. HIV is a retrovirus. What mechanism does the AIDS virus use to reproduce itself throughout the immune system? conjugation transformation binary fission transduction Question 13. 13. A biologist separates a population of fruit flies into two sets. She raises one set on medium containing starch, while the other is raised on medium containing maltose. After many generations, the selection creates two divergent populations (starch and maltose). She then mixes males and females from the different populations into mating cages and measures the mating frequencies. In a control experiment, she takes flies from two populations, each raised on the same medium, mixes them in mating cages, and determines the mating frequency. The data are shown in the table. Mating of flies from different media What information can be interpreted from the data? The starch and maltose flies have converged. The starch and maltose flies are becoming reproductively isolated. The starch flies prey on the maltose flies The starch and maltose flies are becoming temporally isolated. Question 14. 14. Which will result in the change of allele frequency within a population? genetic drift large population size random mating lower mutation rates Question 15. 15. Fossil records help us link common ancestors and provide evidence of evolution. However, it is sometimes difficult to support the phyletic gradualism of such species. What evidence is lacking within the fossil record that would best support this progression over time? punctuated equilibrium analogous structures transitional fossils coevolution between species Question 16. 16. Which action is necessary for Organism D to carry out, but not for Organism B? obtain organic molecules access the sun for energy produce large quantities of energy assemble organic compounds from sunlight Question 17. 17. A biology student investigates the role of diffusion with agar cylinders of different radii and heights. She molds each cylinder so that the difference in height between one cylinder and the next is equal to the difference in radius. (For example, if the height decreases by 0.4 cm, then the radius increases by 0.4 cm). She places each cylinder in a beaker of food dye for 10 minutes. Next, she removes each cylinder and cuts it in half. She measures the depth of diffusion of the dye (a constant 0.8 cm) into the cylinder and calculates the undiffused volume. The data for the experiment are shown in the graphs. Diffusion with agar cylinders Which conclusion regarding the height is correct? As the height increases, the rate of diffusion increases. As the height increases, the rate of diffusion decreases. As the height increases, the undiffused volume increases. As the height increases, the undiffused volume decreases. Question 18. 18. A biochemist studies the fate of pyruvate in four different cell types (A–D). She incubates each cell with 114C-pyruvate and measures the ATP content and the radioactive carbon dioxide, ethanol, and lactic acid produced in each cell type. She repeats the experiment using 2-14C-pyruvate, which is a measure of Krebs cycle activity. The results are shown in the graphs. The fate of pyruvate in four different cell types In Cell C, which process completely oxidizes pyruvate? Krebs cycle glycolysis alcoholic fermentation lactic acid fermentation Question 19. 19. web within an ecosystem is shown in the diagram. food web Which organisms are autotrophs? C and D G and H A and B E and F A food Question 20. 20. Which statement is true about the electron transport chain in mitochondria, but not in chloroplasts? Mitochondria use different acceptors of electrons from the chains than chloroplasts. Only chloroplasts utilize a proton gradient. Mitochondria are coupled to an ATPase, but chloroplasts are not. Only chloroplast chains occur in membranes. Question 21. 21. A toxicologist studies the toxic effects of three substances (A–C) on cultured nerve cells at different concentrations over different times. He measures cell death by the exclusion of trypan blue, which can only enter and stain cells that have disrupted membranes. He measures the leakage of lactate dehydrogenase (LDH), a cytosolic enzyme that leaves cells when the membrane is disrupted. He measures cell blebbing with a fluorescent dye that permeates the intact membrane. Finally, he measures DNA fragmentation with a fluorescent assay that stains for histone-associated DNA in the cytoplasm. The results are shown in the table. studies the toxic effects of three substances A-C on cultured nerve cells at different concentrations over different times Which statement best describes the actions of Substance B? Low and high concentrations of Substance B cause only necrosis. Low concentrations of Substance B cause necrosis, while high concentrations produce apoptosis. Low and high concentrations of Substance B cause only apoptosis. Low concentrations of Substance B cause apoptosis, while high concentrations produce necrosis. Question 22. 22. Why do larger animals eat less in proportion to their size? Larger animals eat more energy-dense food. Interior cells are more insulated and lose less energy has heat. Larger animals tend to travel longer distances than smaller animals. Larger animals move slower and therefore require less energy to function. Question 23. 23. The bonds indicated by the dotted lines are responsible for which property of water? high surface tension molecular mass molecular shape infrared spectrum Question 24. 24. What happens in Step A of the Krebs cycle? Pyruvate gets decarboxylated to form acetyl-CoA. Oxaloacetic acid combines with acetyl CoA to form citric acid. ADP bonds with a phosphate to form ATP. FADH takes on energy, forming FADH2. Question 25. 25. Which action would Animal D be more likely to carry out than Animal B? reducing activity during colder seasons seeking out sunny locations to absorb heat directly stalking prey slowly over a long distance waiting long periods of time between consuming foods Question 26. 26. In which step does fragmentation occur? A B C D Question 28. 28. The diagram shows the light reactions of photosynthesis with various stages labeled (A-D). Process of photosynthesis What happens in Stage D? ATP is made by chemiosmosis. Water is split to form oxygen. High-energy electrons are transported to electron carriers. Light energy is captured. Question 29. 29. graph shows the change in energy during three biochemical reactions (A–C). Biochemical Reaction Which reaction has a free energy change equal to zero? A B C D The Question 30. 30. diagram illustrates the Calvin cycle with various steps labeled A–D Calvin cycle In which phase is carbon fixed? The A B C D Question 31. 31. During childbirth, the increased production of oxytocin causes uterine contractions that assist the baby through the birthing canal. More oxytocin is then produced. Which statement best describes why uterine contractions are an example of a positive feedback mechanism? The brain increases the intensity of uterine contractions until homeostasis has been reached. Pressure from uterine contractions increases with increased levels of oxytocin. The hormones reaching the brain signal the uterine contractions to continue. The production of oxytocin and uterine contractions leads to homeostasis. Question 32. 32. In an experiment, the outer shells of eggs were carefully removed by soaking the eggs in vinegar overnight. The eggs remained intact, protected by the semi-permeable membrane. The eggs were then placed in different solutions for 24 h. The initial and final masses of the eggs were recorded as well as the initial and final volumes of the solutions. The data are shown in the table. Eggs in Vinegar Data Table Which solution was isotonic? A B C D Question 33. 33. Which statement is true regarding homeostasis? (Points : 1) Homeostasis is maintained over long periods of time because of evolutionary forces. Homeostasis is a stable internal environment despite the influences of outside forces. Homeostasis occurs as a direct result of change on the cellular level. Homeostasis is an unstable state within the body despite changes in outside forces. Question 34. 34. Which has two membranes, one with a smooth exterior and the other with a folded interior? (Points : 1) A C B D Question 35. 35. Wind chill is the perception of lower ambient temperatures because of air movement. Which presents the best case that wind chill influences the internal temperatures of animals? A dog shivers when standing in blizzard conditions. Pigs sweat in windy weather. Bears hibernate in winter. A gecko raises its body off rocks, exposing it to wind from all sides. Question 36. 36. In the photo of this savannah ecosystem, which is an abiotic factor? soil moisture content grass density antelope population shrub community Question 37. 37. A study of deer populations was completed to determine if behavior mechanisms reduced the amount of predation occurring in specific areas populated by mountain lions. The amount of food was assessed in three different areas that deer commonly forage. It was also noted that deer spend a significant amount of time scanning the region when feeding on edge habitats of forests. Deer population and food resources data table What do the data indicate about the feeding habits of deer? Deer will change foraging behavior based upon the risk of predation. Deer avoid the forest interior because of the lack of food. Deer feed only where food resources are abundant. Deer feed only where the risk of predation is high. Question 38. 38. Mammalian kidneys are the primary organs for water balance and salt regulation. Mammals with long loops of Henle in their kidneys are adapted to hot, arid environments. What physiological characteristic could be observed in such mammals? highly concentrated urine excretion of salt crystals dilute urine urine with no urea Question 39. 39. Euglena is a unicellular organism that gains nutrients both as an autotroph and heterotroph. In a hypothetical experiment shown, a population of Euglena (green circles) was placed evenly in a shallow aquarium that was shaded on one side and exposed to light on the other. A population of Euglena prey (red triangles) was also placed evenly in the aquarium. The figure shows the results after 24 hours. a population of Euglena and prey exposed to dark and light areas of aquarium What best explains the Euglena behavior? They obtain food equally from autotrophy and heterotrophy. They obtain food equally from heterotrophy and pleiotrophy. They prefer heterotrophy to autotrophy. They prefer autotrophy to heterotrophy. Question 40. 40. What is the likely response after the containment of a pathogen in a plant? Chemical agents are made that pass immunity from cell to cell. A signal transduction pathway elicits the production of phytoalexins and PR proteins. Pathogens are made that construct resins to block other pathogens. A gene-for-gene response launches localized antigens to fight invaders. Question 41. 41. Which correctly identifies the type of immune response depicted by the illustration? humoral response gene-to-gene response cell-mediated response nonspecific immunity Question 42. 42. Manatees are marine mammals that live in ocean, freshwater, and brackish waters in a wide range of salinities. Although osmoregulation is not thoroughly understood in these organisms, which characteristic most likely contributes to their adaptation to a salt water environment? absorbing water concentrating urine ingesting large amounts of salt water passing large amounts of dilute urine Question 43. 43. Calcium ions move out of the cell against a concentration gradient. What drives this active transport? vesicles fusing with the membrane receptor-mediated exocytosis hydrolysis of ATP diffusion Question 44. 44. Which is involved in phagocytosis by amoebas? mitochondria pseudopods endoplasmic reticulum Golgi apparatus Question 46. 46. The blood glucose levels of four patients (A–D) were monitored every 12 hours for nearly one week. The data are shown in the graph. Normal blood glucose is 100 mg/dL. Blood glucose levels of four patients Which patient has the most unstable blood glucose? A B C D Question 47. 47. Nondisjunction usually happens during which phases of meiosis? prophase I and II interphase I and II telophase I and II anaphase I and II Question 48. 48. Compared to a bacterium, which is a unique characteristic of a bacteriophage? contains a circular chromosome of DNA changes its genotype through transformation requires a host cell for reproduction transfers genetic material to conjugation Question 49. 49. Evolutionarily speaking, asexual reproduction increases the likelihood of which process? speciation adaptation mutation cohabitation Question 50. 50. Which enzyme is used in the synthesis of the lagging strand of DNA but not in the synthesis of the leading strand? RNA polymerase DNA ligase helicase DNA-dependent DNA polymerase Question 51. 51. The experimental data of Avery, MacLeod, and McCarthy was the foundation for the study of which scientist(s)? Frederick Griffith Hershey and Chase Watson and Crick Rosalind Franklin Question 52. 52. In a laboratory, a group of students studied asexual reproduction within flatworms. The lab instructor asked the group to carefully slice their worm into three segments. The next week, students returned to class and noticed three complete worms in the dish. Which type of asexual reproduction was demonstrated by the lab exercise? binary fission fragmentation conjugation parthenogenesis Question 53. 53. Scientists observed a piece of nucleic acid with a long terminal repetitive sequence of adenines in a cell. What most likely did they observe? mRNA cDNA rRNA rDNA Question 54. 54. Which statement is true about trisomy disorders? Trisomy disorders are not inherited, but occur from a chromosomal abnormality that occurs at random during gamete formation. Trisomy disorders are inherited mostly from parents with the same disorder. A person with Down syndrome will most often produce a child with Down Syndrome. Trisomy disorders occur in about 15 percent of the population today. Trisomy disorders can first be detected at 15 weeks, and they require advanced prenatal treatment. Question 55. 55. Which is a phase of translation? pronation polyadenylation elongation modification Question 56. 56. In some breeds of cats, deafness is due to a recessive allele (d) of a particular gene, and normal hearing is due to its dominant allele (D). What percentage of the offspring of a normal heterozygous (Dd) cat and a deaf cat (dd) would be expected to have normal hearing? 0% 25% 50% 100% Question 57. 57. When fingers are formed in the womb, they are webbed together. The webbing occurs from the overproduction of temporary cells. Why is this webbing absent at birth? There are no blood vessels in the webbing, so the cells die off. The web cells undergo programmed apoptosis. The acidity of the buildup of fetal urine with the sac removes these cells. As the fetus starts to move its fingers, the thin web tissue tears and degrades. Question 58. 58. Why is most mitochondrial DNA maternal? The zygote receives little, if any, cytoplasm from the sperm. Oogenesis requires less energy and contains less cytoplasmic material. The ratio of gamete production is 4:1. Spermatogenesis is a longer process than oogenesis and uses up most of its energy from mitochondria. Question 59. 59. When describing the process of gametogenesis in males and female, which statement is true? The ratio of gamete production is 2:1. Oogenesis involves continuous division. Mitochondria are not passed to the offspring from the male gamete. Spermatogenesis only occurs during puberty. Question 60. 60. Which occurs at the E site of a ribosome? tRNA leaves the ribosome. Aminoacyl-tRNA enters the ribosome. Peptide bonds form between amino acids. mRNA attaches to the ribosome. Question 61. 61. A genetic disorder due to a recessive allele (a) is lethal for homozygous individuals (aa), but heterozygous individuals (Aa) have no symptoms. Given this information, which is likely to happen? The disorder will be eliminated because there are no recessive homozygotes (aa) around to reproduce. Only homozygous dominant (AA) individuals will survive in each generation. The disorder will remain in the population due to the reproduction of heterozygotes (Aa). The occurrence of the disorder will increase over time throughout each generation. Question 62. 62. A scientist observes a small sample of a protein in its primary structure. He notes the following sequence: MET-ALA-SER-ARG Which was the complementary mRNA strand? CAGAAGCACAGC AUGGCCUCACGU ATGAAGCAAAGT UAC UUAUUUGU Question 63. 63. A hair permanent alters which type of bonds in the hair structure? hydrogen bonds ionic bonds salt bridges disulfide bonds