Reading List - BSC 2005 Unit 2: Moving from Mitosis & Meiosis to Genetics & Evolution

Transcription

1 Inquiry into Life (14 th Ed) by Mader & Windelspecht: Reading List - BSC 2005 Unit 2: Moving from Mitosis & Meiosis to Genetics & Evolution Ch 23 review Ch 5 Ch 24 Ch. 26 Ch 27 Ch 33 Mendel, Genetics Cellular reproduction: mitosis & meiosis Chromosomes and sex- linked inheritance DNA Biotechnology Evolution Behavior: Nature (Genetics) vs Nurture, and the Affect on Fitness Study lecture notes! Know details of examples discussed in class Make a list of all the traits we covered in class Quiz yourself: what is the dominance relationship for each trait? When you get a word problem, what symbols/letters will you use? What category (epistasis, co- dominance, etc) is this example? Read book the book! Practice: test yourself using the questions at the end of each chapter and on the course website. Understand vocabulary and examples for each of concepts listed below: Mitosis vs. meiosis Diploid vs. haploid Daughter cells Germ cells, gametes Crossing over / recombination Chromosomes & Independent assortment Mendelian genetics: Particulate theory vs. blending theory Complete dominance (and recessive) Genotype and Phenotype; genotypic ratio vs. phenotypic ratio Allele vs. gene Homozygous and Heterozygous Monohybrid cross heterozygous for one trait: Aa x Aa Ratio of Genotypes (genotypic ratio) Ratio of Phenotypes (phenotypic ratio) Dihybrid cross heterozygous for two traits: AaBb x AaBb Ratio of Genotypes (genotypic ratio) Ratio of Phenotypes (phenotypic ratio) (continued on next page) 43

2 Post- Mendelian genetics: Co- dominance and incomplete dominance (vs. complete Mendelian dominance) Multiple alleles for a single gene: e.g. A, B and O alleles for blood type (not the Rh+/Rh- ) Pleiotropy Epistasis Polygenic inheritance Impact of environment on phenotypic expression Sex- linked recessive Autosomal recessive inheritance Autosomal dominant inheritance Evolution Artificial vs. Natural Selection Darwinian vs. Lamarckian evolution Impact of environment on allele frequencies Microevolution vs. Macroevolution Directional vs. Stabilizing vs. Disruptive Selection Sympatric vs. Allopatric speciation Prezygotic vs. Postzygotic mechanisms for reproductive isolation Causes of mass extinction Evidence supporting evolution: Comparison of modern life (homologous structures, including molecular/dna homologies) Fossil record indicates progressive change through time Biogeography: patterns of species are not random but arranged by geographic proximity Convergent evolution in similar ecosystems Direct observation of microevolution during historical times. Age of the earth (4.5 billion years ago) and approximate time when major biological events occurred: Earliest evidence of simple, prokaryotic life on earth (about billion years ago) Earliest evidence of eukaryotic life (about 2 billion years ago) All major groups of animals first appear (about 0.5 billion years ago = 500 million years ago) First mammals and dinosaurs appear (about 0.25 billion years ago = 250 million years ago) Dinosaurs become extinct (about 0.07 billion years ago = 70 million years ago) Human ancestors (hominins) first left Africa (about billion years ago = 1 million years ago) Labs: #5 Cell cycle (Mitosis, Meiosis) and Cancer #6 Genotypes, Phenotypes, Mitosis and Meiosis #7 Biotech: blood types, how to interpret DNA fingerprints from gels #8 homologous, analogous and vestigial structures Anatomy is related to environmental adaptations (dental formula and diet) Sexual dimorphisms 44

3 Lecture 11 - Introduction to Mendelian Genetics Lecture Prep: read Chapter 23; review mitosis and meiosis and crossing over In the figures below, a thin line designates DNA inherited from one parent, and a thick line designates DNA inherited from another parent. Which of the processes shown above illustrates mitosis? Which of the processes shown above illustrates meiosis? Which of the processes shown above generates germ cells (gametes) with half the number of chromosomes as the parent cell? Which of the processes shown above illustrates the type of cell division by which a fertilized egg grows into an adult? Which of the processes shown above is used by your liver or skin to create identical cells in order to replace cells that have died? Which of the processes shown above involves recombination of the genes from each parent? How many daughter cells are produced by meiosis? Are the daughter cells produced by meiosis genetically identical? Give one example of a haploid cell. Explain the benefit of crossing over (genetic recombination): 45

4 Lecture Review: Define the following terms: True breeding plant Parental generation F1 generation F2 generation gene allele genotype phenotype heterozygous homozygous genotypic ratio phenotypic ratio 46

5 Give a few examples of phenotypes Mendel observed in pea plants, and the alternate forms that phenotype can take: Example: color of pea seed - yellow or green How many alleles do these pea plants have for each gene that controls a phenotype? Why don t pea plants have more or less alleles? Provides two examples of a homozygous genotype: Can a phenotype be heterozygous? If your phenotype is dominant, your genotype could be (list all that are possible) is (pick any letters you wish to symbolize the alleles) If your phenotype is recessive, your genotype could be (list all that are possible) is (pick any letters you wish to symbolize the alleles) Explain why a phenotype produced by a recessive allele (like green colored peas) might be more common than the phenotype produced by the dominant allele (yellow colored pea). [You might also consider why a trait produced by the dominant allele, such as polydactylism, is less common than the trait produced by the recessive allele]. PRACTICE PROBLEMS: The formation of gametes PRACTICE PROBLEMS: Monohybrid Crosses in a monohybrid cross, we are crossing two individuals who are both heterozygotes (hybrid) for one (mono) gene. PRACTICE PROBLEMS: Dihybrid Crosses in a dihybrid cross, we are crossing two individuals who are both heterozygotes (hybrid) for two (di) different genes: warning...the "hints" demonstrate how to solve these problems the hard way; I recommend using the product rule, as illustrated in class, and on page 469 of the textbook (yet another example of the product rule method can be seen once the answer to the genetics extra credit problem is posted on the course website). Nonetheless, you can use the problems above to test yourself. 47

6 Lecture #12 - Genetics Lecture Prep: read Ch 23 Lecture Review: Define the following terms, & provide an example of each (specify the phenotype associated with each allele) Incomplete dominance Codominance Multiple alleles One gene controls whether a particular species of snake has a diamond pattern on its back and also whether it has a stripe on its belly. You breed a snake with diamonds on its back (but no stripes on its belly) with another snake that has stripes on its belly (but no diamonds on its back). All of their offspring have both diamonds and stripes! What kind of inheritance is exemplified by this example? What are the genotypes of the parents and the offspring? (you can use any symbols you wish to designate the genotype of each parent, and the genotype of the offspring) Are the parents homozygous? Are the offspring homozygous? If you were to breed two of the offspring with each other, what phenotypic ratio would you expect? and what genotypic ratio would you expect? What if you breed one of the offspring with one of its parents (YUCK!)? 48

7 Mary loves dairy products, and suffers no ill effects from eating them, but her husband Joseph is absolutely lactose intolerant (even a little lactose and he s got terrible diarrhea). Joseph and Mary have a child named Jose, and this child can tolerate some dairy products as long as it is not too much. What kind of inheritance is exemplified by this example? Jose goes on to father a child with a woman (who is also named Mary, like Jose s mother, lovers dairy products). What are the possible genotypes of Jose and Mary s children? is the genotypic ratio expected for Jose and Mary s children? What is the probability that Jose and Mary first child will have the same phenotype that he has? If Jose and Mary have three children, what is the probability all three will have the same phenotype as Mary? PRACTICE PROBLEMS: Incomplete Dominance 49

8 Lecture #13 - Genetics Lecture Prep: read Ch 23 Lecture Review: Define the following terms, & provide an example of each (specify the phenotype associated with each allele) Pleiotropy Epistasis Polygenic inheritance Imagine that two genes control the number of eyelashes a person has, and for each gene there are two alleles (one that produces many eyelashes, while the other allele produces very few eyelashes). Brian has the maximum number of eyelashes possible, and he mates with Julia, who has the fewest number of eyelashes possible. What kind of inheritance is exemplified by this example? What are the genotypes of the parents and the offspring? (you can use any symbols you wish to designate the genotype of each parent, and the genotype of the offspring) Are the parents homozygous? Are the offspring homozygous? What phenotypic ratio would you expect in the offspring produced by Brian and Julia? What genotypic ratio would you expect in the offspring produced by Brian and Julia? 50

9 Adult humans have a wide and continuous range of shoe sizes, but most men are near size 10, and most women are near size 7.5. What kind of inheritance is most likely exemplified by this example? Approximately 40% of cats with white fur and blue eyes are deaf. An initial hint that one gene controlled both pigmentation and deafness came from the observation that white cats with one blue eye and one yellow eye were deaf only on the blue- eyed side. What kind of inheritance is most likely exemplified by this example? Phenylketonuria (PKU) is a disease in humans caused by a deficiency of the enzyme phenylalanine hydroxylase. This enzyme converts the essential amino acid phenylalanine to tyrosine. A defect in this gene results (if untreated) in mental retardation, eczema (a skin disorder), and pigment defects that make affected individuals lighter skinned. What kind of inheritance is most likely exemplified by this example? Walter Landauer and Elizabeth Upham observed that chickens that expressed the dominant allele for frizzle gene produced feathers that curled outward rather than lying flat against their bodies (see photo to the right). These same fowls also have abnormal body temperatures, higher metabolic and blood flow rates, greater digestive capacity, and also laid fewer eggs than their wild- type counterparts. What kind of inheritance is most likely exemplified by this example? Ethanol is metabolized into vinegar by a two step- process. In the first step, ethanol is converted into acetaldehyde an enzyme called Alcohol dehydrogenase (let s just call it enzyme A). In the second step, the acetaldehyde is converted into vinegar by a different enzyme called Aldehyde dehydrogenase (lets just call it enzyme B). For each of the two enzymes, A & B, there exist two alleles, one that encodes a functional enzyme (the dominant form, A or B) and one that encodes a mutated and non- functional enzyme (the recessive form, a or b). Consider individuals with the following genotypes; is each individual able to convert ethanol into vinegar? AA BB aa BB Aa Bb Aa bb aa Bb aa bb If you define the phenotype of interest as the ability to metabolize ethanol into vinegar, then what kind of inheritance is most likely exemplified by this example? 51

10 Lecture #14 - Genetics Lecture Prep: read Ch 23 and Ch 24 Lecture Review: Define the following terms, & provide an example of each (specify the phenotype associated with each allele) Sex- linked recessive inheritance Autosomal recessive inheritance Autosomal dominant inheritance PRACTICE PROBLEMS: Sex- linked traits

11 Lecture #15 - Evolution part #1 Lecture Prep: review Chapter 27, and complete the graphing exercise below The common female house flies lays approximately 100 eggs in her one- month life (column E below). How many of those 100 eggs do you think will live long enough to reproduce? Convert this number of surviving flies into a percent (divide by 100), and place it in column G below. Use the starting data for month 0 and your estimate of fly survival rate (column G) to complete the table. Graph the total number of flies in each generation on the graph below (month on the X- axis, total # of flies from each generation, column B, on the Y- axis make sure you label the numbers on the Y- axis) A. month B. Total # of flies (males + females) alive in each generation C. # of male flies D. # of female flies E. how many eggs does each female lay? F. total number of eggs that are laid this generation G. percentage of those eggs that live long enough to reproduce. H. total number of adult flies reproducing in next round (column H from preceding generation) (C = 1/2 of column B) (D = 1/2 of column B) (F = D x E) (your own estimate, use the same % for all rows) (H = F x G) month 53

12 9 Continue the line below to show what you predict the human population will be in 100 years. What factors will affect the overall size of the human population in 100 years? year 54

13 Lecture Review: While watching the movie The Evidence for Evolution, answer the questions below. The Record in the Rocks 1. Name three things that can fossilize. 2. Look at the horse- like skeletons. How are they changing? (i.e., size, number of toes, way of walking, presence of hooves) 3. Scientific evidence suggests that the continents looked very different 350 million years ago (mya). Briefly describe in what ways. Evidence from Living Things 4. Define what homologous structures are. Give three examples. 5. What is divergent evolution? 6. Define what analogous structures are. 7. Give one example of a vestigial structure. 8. According to the video, how can we explain the fact that there are large flightless birds only in the southern hemisphere? 55

14 The Theory of Evolution 9. What did the theory of acquired characteristics stated? Who formulated this incorrect theory? 10. Who formulated the theory of evolution by natural selection? 11. When individuals reproduce, they generate many more offspring than needed to replace the parents. What are some of the reasons why earth is not overrun with the resultant progeny? 12. If characteristics are inherited, those individuals who reproduce are able to pass on their traits to the next generation. This is referred to as 13. What did Darwin mean when he said that there is a struggle for existence? How can this influence which traits accumulate in any given population? 14. What is defined as natural selection? 15. Define convergent evolution and give at least two examples. 16. Why is the number of light and dark peppered moths changing in a population? Is the color characteristic genetically determined? Variation and Evolution 17. What is the definition of a species? 18. When can we say we have a new species (speciation has occurred)? 19. How can you tell when some organisms are a new species, versus variants from the same species? 20. What is artificial selection? Name some species that may change (or have been produced) due to artificial selection? 21. How can new traits appear in a population? Give an explanation at the molecular level. 22. Is it possible to induce mutations in order to create new traits? Which example is shown in the video? 56

15 Lecture # 16- Evolution part #2 - Microevolution Lecture Prep: read of your textbook, and complete the Mechanisms of Microevolution exercise on next two pages. 57

16 Mechanisms of Microevolution. Review pages of your book for this exercise. The purpose of this activity is to analyze a hypothetical situation and determine the mechanism of microevolution involved. In each of the following scenarios, there is at least one mechanism of microevolution occurring, but possibly more. How many can you identify? Word bank: mutation nonrandom mating directional selection sympatric speciation genetic drift natural selection disruptive selection allopatric speciation gene flow artificial selection stabilizing selection 1. A type of short ground clover grows in a remote meadow near the top of a mountain. The meadow is small, with only enough space for about 100 clover plants to grow. A DNA replication error occurs during oogenesis in one of these clovers. This error changes the DNA sequence of a plant growth gene (g), thereby producing an egg with a new allele (G). This egg is successfully fertilized by a wildtype (g) pollen, giving rise to a heterozygote clover (Gg). Because of the G allele, the Gg heterozygote initiates germination faster than the gg clovers. Which evolutionary processes are involved in this scenario? 2. Because the heterozygote (Gg) clover germinates faster than its neighboring clovers, it is taller and gets more sunlight than its shaded neighboring clovers. The additional sunlight enables the Gg clover to produce more pollen than its neighbors, and over the course of a few growing seasons, the G allele becomes more common. Which evolutionary processes are involved in this scenario? 3. A few years pass, and as the G allele becomes increasingly common, a few GG genotypes are produced. As it turns out, the G allele exhibits incomplete dominance, so the GG genotype grows even faster (and therefore taller) than the Gg genotype. Over the next few growing seasons, the GG genotype becomes even more common than the Gg genotype. Which evolutionary processes are involved in this scenario? Use the space below to make a bar graph that illustrates the initial genotype frequency of the population after scenario #1. Use the space below to make a bar graph that illustrates the new genotype frequency of the population after scenario #3. 58

17 4. A wandering herd of goat pass through the meadow. The goats like eating the clover flowers, but tend to eat the tallest flowers in the patch. In the few days the goats are in this meadow, they eat almost all the tall flowers. Which evolutionary processes are involved in this scenario? Predict what clover genotype would be most fit if the goats returned to this meadow regularly: Use the graph to the right to make a bar graph that illustrates what you expect genotype frequency would look like if scenario #3 and #4 persisted for many generations. 5. The short ground clover is normally pollinated by a beetle that lives on the ground. This beetle does not often crawl up to the tallest flowers (perhaps because it would be more easily eaten by birds). However, as the tall GG plants become more common, butterflies begin to pollinate the GG plants (the butterflies rarely pollinate the short gg plants, perhaps because the flowers on the short plants are more difficult for the butterflies to reach). Fortunately for the clovers, there is enough pollen and pollinators to ensure that nearly every egg is successfully fertilized, regardless of the plants height and pollinator. Which evolutionary processes are involved in this scenario? Suggest a possible explanation for why birds might eat the beetles but not the butterflies. Use the graph to the right to make a bar graph that illustrates what you expect the genotype frequency would look like if scenario #5 persisted for many generations. (assume the herd of wandering goats does not return to this meadow). 6. It turns out that some of the taller plants eaten by goats in scenario 4 had already been pollinated and produced seeds with a protective outer coating. Therefore, the goats ate these seeds along with the flowers, and then wandered many miles away, depositing seeds as they went. Because the goats ate almost only the tall flowers, most of the seeds in their poop was the GG genotype. Some seeds were deposited in a remote meadow where only short (gg) clovers were growing while other seeds were deposited in a windy, rocky mountain pass where no clovers had previously existed. The butterflies and beetles that pollinate this clover don t usually visit rocky, windy areas, so the clover growing in the rocky areas became dependent on the wind to pollinate its flowers. Various alleles of another gene (H or h) affect the size and weight of the pollen, which then affects how easily the pollen is spread by the wind. Which evolutionary processes are involved in this scenario? 7. Within a few years, the clovers on the mountain pass grew into a lush clover patch; but in one particularly hard winter, 99% of the clovers froze and died. It turns out that one clover (and its few descendants) had a mutation that shifted energy storage from predominantly starch to a related a polysaccharide called inulin, and the inulin prevented these plants from freezing. Which evolutionary processes are involved? 59

18 Lecture # 16- Evolution part #2 Microevolution Lecture Review: Classify the following scenarios as examples of either artificial or natural selection by placing the letter for each scenario into the appropriate box below. Scenarios A. Rattlesnakes blend in with their wooded surroundings. B. Desert plants, such as cacti, are adapted to store water during dry conditions. C. A variation that increases the speed of a rodent increases its chances of escaping predators and reproducing. D. A dog breeder wants the agility of a border collie and the coloring of an Australian shepherd, so he breeds the two. E. A gardener choses the seeds from a rose that produces larger flowers to plant. F. Brussel sprouts, kohlrabi, and Chinese cabbage are domesticated plants that all descended from the same ancestor. Artificial Selection Natural Selection Use the terms on the right to complete the sentences below. Each term is used only once. All living organisms use similar biomolecules, suchas, RNA, ATP and proteins. This leads scientists to conclude that all life descended from a common ancestor that also used these. Organisms also use the same genetic code (Universal Codon Chart) to specify which is encoded by a particular 3- nucleic acid codon when building proteins. Thus, differences between species exist mainly due to small difference between the each one produces and uses. A. RNA B. DNA C. proteins D. amino acid E. biomolecules 60

19 Use the terms on the right to complete the sentences below. Some terms may be used more than once. Structures that are anatomicallly similar because they were inherited from a common ancestor are called structures. For example, the forearms of a bat, bird, whale and cat all contain the same of bones, but each serves a different. Some inherited structures are no longer necessary and lose their original function, in which case they are considered structures. The presence of these non- functional structures implies descent from an ancestor that once had a functional form. Oppositely, structures are those that serve the same function in two organisms, but are anatomically different and don t share a common ancestry. A. analagous B. function C. homologous D. arrangement E. vestigial The presence of structures, not analogous structures, is evidence that organisms are related. Scientists conclude that all life descended from a common ancestor because they share biomolecules such as DNA, RNA and proteins. Classify the following examples as either homologous or analogous structures by placing the letter for each example into the appropriate box below. examples A. Cactuses and spurges have convergent (similar but independent) adaptations to hot climates. B. Forearms of chickens, whales, and humans. C. Insect wings and bat wings. D. Structures that are related to each other because of descent from a common ancestor. E. Toe of a horse and wing of a bat. F. Arise because of adaptations to the same type of environment. G. Structures with the same function but different evolutionary ancestry. Homologous Structures Analogous structures Explain how vestigial traits and homologous traits (including both anatomical and biochemical features) support the theory of evolution. 61

20 Classify the following examples by placing the letter for each example into the appropriate box below. A. British land snails have two very different phenotypes as they are both adapted to different habitats. B. Individual finches within one population occupy different niches and eventually evolve to have different beak sizes. C. Very large and very small newborns are more likely to suffer serious health problems. D. Chloroquine is no longer effective against malaria because it has evolved resistance against it. E. A new flu vaccine is needed every year. F. Bird clutch size consisting of 4-5 eggs are more likely to hatch than larger or smaller clutches. Disruptive selection Stabilizing selection Directional selection Use the space below each graph to illustrate how the initial population distribution that is shown would change after undergoing disruptive, stabilizing, or directional selection. The x- axis represents the phenotype of the population being measured, such as the size of an animal (small animals on the left, medium sized animals in the middle, and larger animals on the right). The y- axis is the frequency of each phenotype in the population (i.e. the number of individuals in the population that are small, medium or large). Initial Population Distributions: small large small large small large size size size New Population Distribution After Selection: Disruptive selection stabilizing selection directional selection small large small large small large size size size 62

21 Use the terms on the right to complete the sentences below. Some terms may be used more than once. Sickle cell is a genetically inherited disorder that affects molecules that carry oxygen in the blood. Individuals that are have the sickle cell disease, while individuals that belong to the other two genotypes do not. Individuals that carry an allele for sickle cell also carry a resistance to malaria, as the sickle shaped lack and malarial parasites die. Therefore, individuals that are carry an advantage, as they are resistant to malaria and do not have sickle cell disease. A. autosomal dominant B. homozygous dominant C. heterozygous D. homozygous recessive E. autosomal recessive F. hemoglobin G. white blood cells H. red blood cells I. calcium J. potassium Use the terms on the right to complete the sentences below. Some terms may be used more than once. A process where small measurable changes occur from generation to generation is called. A process where large changes occur over long periods of time is called. This process requires, or the splitting of one species into two or more new species, to occur. The describes a species as groups of organisms that interbreed, have a shared, and are reproductively isolated from all other species. One limitation of this way of defining species is that it applies only to organisms. A. asexually reproducing B. biological species concept C. extinct D. gene pool E. macroevolution F. microevolution G. natural selection H. sexually reproducing I. speciation Classify the following examples by placing the letter for each example into the appropriate box below. Examples of reproductive barriers A. F2 fitness B. habitat isolation C. gamete isolation D. zygote mortality E. hybrid sterility F. behavioral isolation G. temporal isolation H. mechanical isolation Postzygotic isolating mechanisms Prezygotic isolating mechanisms 63

22 Use the terms on the right to complete the sentences below. Some terms may be used more than once. In order to mate, male blue- footed boobies must display an elaborate courtship dance. This is an example of. Because sugar maples and red maples occupy different habitats, they do not exchange pollen, even though they live in the same locations. This is an example of. Male insects of a species have reproductive genitalia that make it impossible to reproduce with females of other closely related organisms. This is an example of. Two species of termites live in the same location but don t mate because they have different breeding seasons. This is an example of. Pollen of one species of flower is not able to survive the journey to reach the egg produced in embryo sac of a flower of another species, so they cannot reproduce together. This is an example of. A. behavioral isolation B. habitat isolation C. mechanical isolation D. gamete isolation E. hybrid sterility F. temporal isolation Classify the following examples by placing the letter for each example into the appropriate box below. Examples A. Speciation that is based on geographic separation. B. Organisms in different locations are subject to different selective pressures and evolve into different species. C. Organisms are reproductively isolated by postzygotic mechanisms and evolve into different species. D. Speciation that does not require geographic isolation. E. Bread wheat evolved from two species of wheat with different numbers of chromosomes. Allopatric speciation Sympatric speciation Use the terms on the right to complete the sentences below. Rapid and dramatic is a significant cause of extinction. The changed global weather patterns and the amount of shoreline and interior land, leading to the Permian mass extinction of and terrestrial organisms 250 million years ago. High levels of iridium and a large crater in the Gulf of Mexico indicate the impact of a giant during the Cretacious period 66 million years ago. This impact would likely have caused large environmental changes including a prolonged global winter, and is believed to have contributed to a mass extinction that killed of the. There appears to be an on- going mass extinction caused by. A. drifting of continents B. environmental change C. dinosaurs D. meteorite E. human- induced environmental changes F. marine 64

23 Lecture # 17- Evolution part #3 Human evolution Lecture prep: Watch the TED talk: Debunking the Paleo diet by Christina Warinner There is a link under the cool science tab on the course website. Compare this talk to the TED talk we watched earlier (Minding your mitochondria). Is there anything we can conclude from these two talks? Lecture Review: prepare for the unit #2 exam! 65

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