Multiple Choice Short Answers Fill in the blink Definition BONUS! 10 10 10 10 20 20 20 20 20 20 30 30 30 30 30 40 40 40 40 60 50 50 50 Bonus! 10 70 Multiple Choice - 10 What is the ultimate source of variation in a population? 1) 2) 3) 4) Mutation Asexual reproduction Mitosis Natural selection • Answer 1 – 10 Answer: 1, that’s right! Mutation in DNA is the ultimate source of variation in a population Multiple Choice- 20 Which process tends to reduce variety within a population? 1) 2) 3) 4) Natural Selection Random fertilization Independent assortment Crossing over Multiple Choice Answer – 20 Answer: 1, natural selection tends to reduce variety within a population. Remember the survival of the fittest? Multiple Choice- 30 Which factor is NOT an important part in natural selection? 1) Competition within a species 2) Selective breeding of domestic plants and animals 3) Heritable variation 4) Limited environmental resources Multiple Choice Answer– 30 Answer: 2, selective breeding of domestic plants and animals is not an important part in natural selection. Why? Because selective breeding or artificial selection is one of the evidences of evolution, not the important part in natural selection! Multiple Choice- 40 What is the mechanism of natural selection? 1) After a change in the environment, a species will evolve adaptations to the new conditions 2) Any individuals in a population can be selected entirely by chance 3) If an adaptation to the environment is useful, an individual will develop it and pass it on to its offspring 4) Variations amongst individuals of a population are selected by a changing environment Multiple Choice Answer– 40 Answer: 4, mechanism of natural selection is variations amongst individuals of a population are selected by a changing environment Multiple Choice- 50 Why has antibiotic resistance evolved in bacteria? 1) All bacteria reproduce quickly 2) Varieties of bacteria resistant to antibiotics reproduce faster than non-resistant varieties 3) Bacteria showing resistance to antibiotics survive after antibiotics are used 4) Bacteria exposed to antibiotics developed a resistance to them Multiple Choice Answer– 50 Answer: 3, bacteria showing resistance to antibiotics survive after antibiotics are used and thus, through the process of natural selection, the bacteria with beneficial variation has more chance to pass on the beneficial characteristics to its offspring! Short Answer- 10 State two reasons why individuals in the population have to compete for resources. Answer– 10 Because of limited resources and over-production, the individuals that have the same needs then have to compete for the same recourses. Short Answer- 20 How does sexual reproduction increase variation in a population? (suggest 2 ways) Answer– 20 Sexual reproduction can increase variation by 1) Crossing over and random assortment of homologous chromosome in meiosis 2) Random fertilization 3) Combining alleles from two parents (1/2 from each) Short Answer- 30 Explain the development of antibiotic resistance in bacteria. (How does it happen?) Answer– 30 Antibiotics are a change in environment, and any mutation that helps bacteria survive antibiotics will increase through natural selection. Overtime, the bacteria with beneficial variation will survive and reproduce more, passing the useful variation to the offspring. Eventually, resistance will evolve. Short Answer- 40 Why are there more dark (melanistic) forms of pepped moths than the light (speckled) forms in the polluted environment? Answer– 40 Because in the polluted environment, the color of the dark forms act as effective camouflage that makes them difficult to spot by predators, and thus increases their chance to survive and reproduce. The dark forms then have higher chance to pass on the beneficial characteristics to their offspring comparing to the light forms. Thus, overtime, the darks forms will have more offspring than the light forms do, maximizing their population Short Answer- 50 State the Darwin-Wallace theory of evolution by Natural Selection. Answer – 50 1. 2. 3. 4. Genetic variation exists within a population More offspring are born than can survive to reproduce Resources are limited Because of over-reproduction, individuals of the same species must compete for resources 5. Some variation in the population will be more useful in the competition for resources/ survival/ reproduction. 6. Individuals with beneficial variations will survive loner and/or reproduce more frequently 7. The beneficial variations become more common and the changes add up over time; this the population changes over time. Fill in the Blank- 10 Natural selection can only occur if there is _____ among members of the same species. Answer– 10 Natural selection can only occur if there is variation among members of the same species. Fill in the Blank- 20 _____ are the characteristics that make an individual suited to its environment and way of life. Answer– 20 Adaptations are the characteristics that make an individual suited to its environment and way of life. Fill in the Blank- 30 _____ and _____ independently developed the theory of Natural Selection. Answer – 30 Charles Darwin and Alfred Wallace independently developed the theory of Natural Selection Fill in the Blank- 40 In order for natural selection to work, variation must be____. Answer – 40 In order for natural selection to work, variation must be heritable. Examples of heritable variations? Skin color, hair color and eye color Fill in the Blank- 50 Individuals with beneficial variation will _____ and _____, leading the beneficial variations to become more common. Answer– 50 Individuals with beneficial variation will survive longer and reproduce more, leading the beneficial variations to become more common. Definition- 10 Define natural selection Answer – 10 Natural selection is the “survival of the fittest” or “the mechanism that increases the chance of certain individuals reproducing” Definition- 20 Define species Answer– 20 Species are groups of organisms that can potentially interbreed to produce fertile offspring. Definition- 30 Define gene mutation Answer – 30 Gene mutation is a change to the base sequence of a gene. Definition- 40 Define evolution Answer– 40 A genetic change in a population or species overtime, which is often the result of natural selection. Bonus Question- 10 True or false, characteristics acquired during the lifetime of an individual are not heritable. Answer – 10 Answer: true! The characteristics acquired during the lifetime of an individual are not heritable. Bonus Question - 20 Natural Selection _____ the frequency of characteristics that make individuals better adapted and _____ the frequency of other characteristics leading to changes within the species. Answer – 20 • Natural Selection increases the frequency of characteristics that make individuals better adapted and decreases the frequency of other characteristics leading to changes within the species. Bonus Question - 20 Suggest two ways that can help slow down the antibiotic resistance. Answer – 20 Ways to slow down the antibiotic resistance 1) Take antibiotic as directed 2) Limit antibiotic use for non-medical uses (in hand soap, livestock or crops) 3) Give antibiotics only when needed for bacterial infections Bonus Question - 30 State three key points about natural selection that are illustrated in the pictures. Answer – 30 The possible key points are 1) Genetic variation exists within a population 2) Some variations are more beneficial than the others 3) Individuals with beneficial variations will survive and reproduce more 4) The beneficial variation become more common and the changes add up over time: evolution occurs Bonus Question - 60 With reference to the graphs, explain the relationship between the average beak size of finches on Daphne Major and the average size of seeds available during 1977-1980. Suggest the reason behind it. Answer – 60 The graph show the positive relationship between the average beak size of the finches and the average size of seeds available. Since there is a variation in finches, with different beak sizes, during the drought that caused the seeds to become bigger and harder, the natural selection occurred causing some finch variations with small beaks to die out. On the other hand, the beneficial variations with large beak sizes had more chances to survive and reproduce, passing the characteristics to the offspring. And thus, evolution occurred causing the average beak size to increased. Bonus Question - 70 Explain evolution of a species by natural selection in response to environment change. Answer – 70 The answer should include: 1) Species show variation 2) Variation in inherited 3) Species have the potential to produce more offspring that can survive 4) Resources are limited 5) Those that are best adapted survive to reproduce 6) This leads to a population adapted to the environment 7) As the environment changes those that are best adapted will have more offspring 8) This will cause the species to evolve to a new adaptation/ change in gene frequencies.