EXAM 3 BIO 20 WRITTEN QUESTIONS WITH ACCURATE GUARANTEED ANSWERS.

What is the authors' purpose for WWGS ? - correct answer It applies natural selection and other ultimate (evolutionary) perspectives to understand why we are imperfect What was Mark Twain's insight into anxiety? - correct answer People suffer from problems that don't actually exist. What is the central paradox exposed by WWGS? - correct answer We possess intricate adaptations yet still suffer from crude problems Which are examples of proximate perspective (as opposed to an ultimate/evolutionary perspective)? - correct answer biochemistry physiology and anatomy how nausea can be caused by the inner ear Which are examples of ultimate perspectives? - correct answer why an illness like morning sickness might actually be beneficial with respect to reproductive success trade-offs between different selective pressures questions about the environment in which we evolved natural selection Natural selection ultimately acts on individuals, not genes. - correct answer false Social Darwinism is an important contribution to intellectual thought because it can inform our values. - correct answer false In humans, genes make up ______% of our DNA. - correct answer less than 5 The estimate of the number of genes in the human genome has dropped steadily over the last 40 years. Recently the number has changed more slowly. approximately what is the current number? - correct answer 20,000 How many thousands of bases (kb) is the human genome? - correct answer 3,000,000 The complete set of an organisms DNA is called a ____ (one word, rhymes with "phone". Must be spelled correctly) - correct answer genome Genotype is to phenotype as: (pick the 3 best) - correct answer a. software language is to i-phone application c. alphabet is to book d. recipe is to dinner Why are gall bladder cells different from lung cells? - correct answer b. They express their genes differently. How do animals such as ourselves develop from 2 cells to millions of different kinds of cells? - correct answer Cells express their genes differently. Lead is a teratogen (interferes with development). IAssume both of the following were true: Individuals of one genotype are more sensitive to lead during development than those with a different genotype, and individuals vary in their exposure to lead. This would be an example of - correct answer gene-environment interaction Mitosis results in: - correct answer new cells with the same number and composition of chromosomes. All non inherited (non congenital) forms of cancer results from - correct answer mutations in cells that undergo mitosis Tanning beds are - correct answer mutagenic carcinogenic Which of the following are features that distinguish cancer cells from normal cells? - correct answer Normal cells have contact inhibition; cancer cells have no contact inhibition. Normal cells can divide a finite number of times; cancer cells can divide indefinitely. Which of the following are likely mutagens? - correct answer . High energy radiation that can break covalent bonds Tanning beds Chemicals that bind to DNA Errors during DNA replication Chemicals that interfere with DNA repair enzymes Any virus that inserts a copy of its genome into your genome which is NOT true of the HPV vaccine? It.... - correct answer rarely, but sometimes causes anal and penis cancer if given to men The HPV vaccine - correct answer is safe. is ineffective if received after HPV infection. prevents most cancers that arise from HPV. What are some consequences of a mutation that reduces the efficiency of ALDH? - correct answer The metabolic removal of acetaldehyde will slow. Acetate production will slow. Many genetic diseases result from mutations that cause a gene to produce a non-functioning ______________, which in turn blocks the functioning of a metabolic pathway. - correct answer . enzyme Organic evolution is - correct answer a change in the frequency of alleles in a population across generations. Which of the following statements is true of Darwin's theory of natural selection? - correct answer All species have the ability to produce more offspring than can survive. New mutant alleles will increase in frequency if they contribute to versions of traits that make individuals leave more descendants. Some phenotypic variation found in populations is heritable. Evolution occurs - correct answer only via natural selection, genetic drift, migration, or mutation What is the effect of mutation on any population? Choose two. - correct answer mutation creates alleles. mutation is the ultimate source of genetic variation. If the ability to digest lactose is dominant and the frequency of the allele L that confers the ability to digest lactose is 0.5, what is the frequency of individuals who are able to digest lactose? (Hint: write down all 3 possible genotypes and calculate the frequencies of the 2 which satisfy the question). - correct answer 0.75 The ability to digest flooble requires at least one allele (F). The frequency of (F) is 0.8. What is the frequency of individuals who CAN'T digest flooble? Hint: write out the possible genotypes... - correct answer 0.04 Diseases caused by loss of function mutations tend to be recessive and fairly rare. Hemophilia is such a disease and has a frequency of 1/10,000. That means that two identical loss of function alleles must come together in one person. Each event (allele h) is independent. What is the frequency of allele h? - correct answer 0.01 In class you learned about 'stabilizing' selection. There are three basic types of selection. Use the internet to find the name of the the name of selection that occurs when a population changes such that one end of the distribution has higher reproductive success (e.g., if babies with higher birth weight had higher survival). - correct answer directional selection. Many mosquito populations today are resistant to pesticides that were historically effective. This pesticide resistance arose in these populations because: - correct answer Some individuals were resistant to the pesticides before they were used, and those mosquitoes were more likely to survive and reproduce than individuals that lacked resistance. Some of the resistance was heritable. Most complex traits show a normal (bell shaped) distribution of values, e.g., starvation resistance. Suppose that instead of a normal distribution of starvation resistance, a population consisted only of flies that all died after exactly 30 hours without food (i.e., there is zero variation for the trait). Imagine how the curve below would now look. Under what conditions would such a population evolve greater starvation resistance? Assume that the trait (starvation resistance) has some heritability. Hint: 2 things must happen. - correct answer If flies with lower starvation resistance reproduced fewer offspring. If there were new mutations that created variation in starvation resistance. Which are true of congenital analgesia? Use the internets. - correct answer Answers: It is synonymous with Congenital Insensitivity to Pain. Children with this condition will sometimes bite off the tip of their tongue. Unnoticed infections and corneal damage due to foreign objects in the eye are common. An afflicted person cannot feel (and has never felt) physical pain. Because people lack pain they are less likely to seek treatment for injuries and infections until the problems become severe. . Affected individuals can feel touch and sometimes temperature. The last common ancestor of humans and other apes lived ___ million years ago. Enter a whole number (e.g. "10") - correct answer 5 The average species exists for 1-3 million years before become extinct, or evolving sufficiently that it should be considered a different species from the fossils that preceded it. Which species appear to have first harnessed fire? - correct answer Australopithecus afarensis Australopithecus africanus Convergent evolution can occur only when two species: - correct answer evolve under similar selective forces Which of the following are likely examples of vestigial characteristics? Just think about what 'vestigial' means. Most can be answered without looking up information. Some will require Google. I'm giving you some ANSWERS: d, e, m, q, r, s ARE NOT VESTIGIAL. You're welcome. - correct answer a. molars in bats that consume a completely liquid diet Correct b.