Biology BSC 2011 UPDATED TEST QUESTIONS WITH 100%VERIFIED SOLUTION

Biology BSC 2011 UPDATED TEST QUESTIONS WITH 100%VERIFIED SOLUTION 8) Charles Darwin was the first person to propose A) that evolution occurs. B) a mechanism for how evolution occurs. C) that Earth is older than a few thousand years. D) a mechanism for evolution that was supported by evidence. E) that population growth can outpace the growth of food resources. - answers D) a mechanism for evolution that was supported by evidence 9) Which of these conditions should completely prevent the occurrence of natural selection in a population over time? A) All variation between individuals is due only to environmental factors. B) The environment is changing at a relatively slow rate. C) The population size is large. D) The population lives in a habitat where there are no competing species present. - answers A) All variation between individuals is due only to environmental factors. 10) Natural selection is based on all of the following except A) genetic variation exists within populations. B) the best-adapted individuals tend to leave the most offspring. C) individuals who survive longer tend to leave more offspring than those who die young. D) populations tend to produce more individuals than the environment can support. E) individuals adapt to their environments and, thereby, evolve. - answers E) individuals adapt to their environments and, thereby, evolve. Answer: E 11) Which of the following represents an idea that Darwin learned from the writings of Thomas Malthus? A) Technological innovation in agricultural practices will permit exponential growth of the human population into the foreseeable future. B) Populations tend to increase at a faster rate than their food supply normally allows. C) Earth changed over the years through a series of catastrophic upheavals. D) The environment is responsible for natural selection. E) Earth is more than 10,000 years old. - answers B) Populations tend to increase at a faster rate than their food supply normally allows. events, under the influence of natural selection? 1. Well-adapted individuals leave more offspring than do poorly adapted individuals. 2. A change occurs in the environment. 3. Genetic frequencies within the population change. 4. Poorly adapted individuals have decreased survivorship. A) 2 → 4 → 1 → 3 B) 4 → 2 → 1 → 3 C) 4 → 1 → 2 → 3 D) 4 → 2 → 3 → 1 E) 2 → 4 → 3 → 1 - answers A) 2 → 4 → 1 → 3 13) A biologist studied a population of squirrels for 15 years. During that time, the population was never fewer than 30 squirrels and never more than 45. Her data showed that over half of the squirrels born did not survive to reproduce, because of both competition for food and predation. In a single generation, 90% of the squirrels that were born lived to reproduce, and the population increased to 80. Which inference(s) about this population might be true? A) The amount of available food may have increased. B) The parental generation of squirrels developed better eyesight due to improved diet; the subsequent squirrel generation inherited better eyesight. C) The squirrels of subsequent generations should show greater levels of genetic variation than previous generations, because squirrels that would not have survived in the past will now survive. D) Three of the statements above are correct. E) Two of the statements - answers E) Two of the statements above are correct. 14) Which of the following must exist in a population before natural selection can act upon that population? A) genetic variation among individuals B) variation among individuals caused by environmental factors C) sexual reproduction D) Three of the responses are correct. E) Two of the responses are correct. - answers A) genetic variation among individuals 15) Which of Darwin's ideas had the strongest connection to Darwin having read Malthus's essay on human population growth? A) descent with modification B) variation among individuals in a population C) struggle for existence D) the ability of related species to be conceptualized in "tree thinking" E) that the ancestors of the Galápagos finches had come from the South American mainland - answers C) struggle for existence 16) If Darwin had been aware of genes, and of their typical mode of transmission to subsequent generations, with which statement would he most likely have been in agreement? A) If natural selection can change one gene's frequency in a population over the course of generations then, given enough time and enough genes, natural selection can cause sufficient genetic change to produce new species from old ones. B) If an individual's somatic cell genes change during its lifetime, making it more fit, then it will be able to pass these genes on to its offspring. C) If an individual acquires new genes by engulfing, or being infected by, another organism, then a new genetic species will be the result. D) A single mutation in a single gene in a single gamete will, if perpetuated, produce a new species within just two generations. - answers A) If natural selection can change one gene's frequency in a population over the course of generations then, given enough time and enough genes, natural selection can cause sufficient genetic change to produce new species from old ones. 18) Currently, two extant elephant species (X and Y) are placed in the genus Loxodonta, and a third species (Z) is placed in the genus Elephas. Thus, which statement should be true? A) Species X and Y are not related to species Z. B) Species X and Y share a greater number of homologies with each other than either does with species Z. C) Species X and Y share a common ancestor that is still extant (in other words, not yet extinct). D) Species X and Y are the result of artificial selection from an ancestral species Z. E) Species X, Y, and Z share a common ancestor, but nothing more can be claimed than this. - answers B) Species X and Y share a greater number of homologies with each other than either does with species Z. 19) The rise of methicillin-resistant Staphylococcus aureus (MRSA) can be considered to be an example of artificial selection because A) humans purposefully raise MRSA in large fermenters in an attempt to make the bacteria ever-more resistant. B) S. aureus is cultivated by humans to replenish the soil with nutrients. C) humans synthesize methicillin and create environments in which bacteria frequently come into contact with methicillin. D) Humans are becoming resistant to bacteria by taking methicillin. - answers C) humans synthesize methicillin and create environments in which bacteria frequently come into contact with methicillin. 20) In a hypothetical environment, fishes called pike-cichlids are visual predators of algae-eating fish (in other words, they locate their prey by sight). If a population of algae-eaters experiences predation pressure from pike-cichlids, which of the following is least likely to be observed in the algae-eater population over the course of many generations? A) selection for drab coloration of the algae-eaters B) selection for nocturnal algae-eaters (active only at night) C) selection for larger female algae-eaters, bearing broods composed of more, and larger, young D) selection for algae-eaters that become sexually mature at smaller overall body sizes E) selection for algae-eaters that are faster swimmers - answers C) selection for larger female algae-eaters, bearing broods composed of more, and larger, young 21) DDT was once considered a "silver bullet" that would permanently eradicate insect pests. Today, instead, DDT is largely useless against many insects. Which of these would have been required for this pest eradication effort to be successful in the long run? A) Larger doses of DDT should have been applied. B) All habitats should have received applications of DDT at about the same time. C) The frequency of DDT application should have been higher. D) None of the individual insects should have possessed genomes that made them resistant to DDT. E) DDT application should have been continual. - answers D) None of the individual insects should have possessed genomes that made them resistant to DDT. 22) If the bacterium Staphylococcus aureus experiences a cost for maintaining one or more antibiotic-resistance genes, then what should happen in environments from which antibiotics are missing? A) These genes should continue to be maintained in case the antibiotics ever appear. B) These bacteria should be outcompeted and replaced by bacteria that have lost these genes. C) The bacteria should try to make the cost worthwhile by locating, and migrating to, microenvironments where traces of antibiotics are present. D) The bacteria should start making and secreting their own antibiotics. - answers B) These bacteria should be outcompeted and replaced by bacteria that have lost these genes. 24) If two modern organisms are distantly related in an evolutionary sense, then one should expect that A) they live in very different habitats. B) they should share fewer homologous structures than two more closel