* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download solutions
Skewed X-inactivation wikipedia , lookup
Inbreeding avoidance wikipedia , lookup
Genome evolution wikipedia , lookup
Minimal genome wikipedia , lookup
Non-coding DNA wikipedia , lookup
Cell-free fetal DNA wikipedia , lookup
Heritability of IQ wikipedia , lookup
Oncogenomics wikipedia , lookup
Site-specific recombinase technology wikipedia , lookup
Quantitative trait locus wikipedia , lookup
Frameshift mutation wikipedia , lookup
Epigenetics of human development wikipedia , lookup
Neuronal ceroid lipofuscinosis wikipedia , lookup
Human genetic variation wikipedia , lookup
Genomic imprinting wikipedia , lookup
Fetal origins hypothesis wikipedia , lookup
Genetic engineering wikipedia , lookup
Genetic drift wikipedia , lookup
X-inactivation wikipedia , lookup
Epigenetics of neurodegenerative diseases wikipedia , lookup
Dominance (genetics) wikipedia , lookup
Artificial gene synthesis wikipedia , lookup
Population genetics wikipedia , lookup
Public health genomics wikipedia , lookup
Nutriepigenomics wikipedia , lookup
Point mutation wikipedia , lookup
History of genetic engineering wikipedia , lookup
Biology and consumer behaviour wikipedia , lookup
Designer baby wikipedia , lookup
Genome (book) wikipedia , lookup
BIOLOGY Sem 2 Topic Test 2012 - ANSWERS Use the following family tree for hemophilia, a sex linked trait, to answer question 1. I 1 II III 1. 2 1 2 3 4 2 1 5 3 6 4 Is the condition dominant or recessive? Give the evidence for your answer. Recessive. Individual III3 receives an X chromosome from II6 and a Y chromosome from II5. Since the individual has the disease, the X must contain the disease. Yet it does not show in III6 meaning it is recessive. 2. Write down the genotypes for each individual. If it cannot be determined, write all possibilities. Xh – diseased chromosome, XH – normal chromosome I1 - XhXh I2 - XhY H II1 - X Y II2 - XhXh II3 - XhXh II4 - XhXh II5 - XhY II6 - XhXH h H h h H III1 - X X III2 - X Y III3 - X Y III4 - X Y 3. If individual III2 married a carrier female, what are the chances that they would produce an offspring that would suffer from hemophilia? What is the chance that a son would suffer? What is the chance that a daughter would suffer? Xh Y h X XhXh XhY XH XhXH XHY 50% offspring suffer from disease. ½ The sons (others are fine). ½ the daughters (others are carriers). 4. The following list has the steps in natural selection jumbled. Un-jumble them into the correct order. i. The environment changes which causes some vi. Variation in the gene pool individuals to die vii. The individuals that are benefited by their ii. A greater proportion of the population beneficial genes survive to a reproductive now contain the beneficial genes age. iii. Mutations that occur in a species leads to viii. The beneficial genes are passed on to the iv. If the environment changes in the same next generation. way in the future as it did in the past then ix. This has led to the species evolving less individuals of the population will die out v. Order – III A few individuals contain beneficial genes that help them survive the environmental change VI I V VII VIII II IV IX 5. Draw a labeled diagram to explain how an animal is cloned 6. What is gene splicing and how does it relate to the use of insulin for diabetics? Gene splicing is taking a section of DNA from one organism and inserting it into the DNA of another. Insulin needed by diabetics is made by bacterium which normally do not make it. The DNA sequence of base pairs which instructs a cell to make insulin is spliced into bacterium’s normal DNA which changes how the cell operates. 7. What does IVF stand for? In-vitro fertilisation 8. Name three issues relating to the use of IVF. Age of recipient(s), same sex couples, costs, when does life begin (discarded embryos). 9. Give the 5 steps required for a cycle of IVF treatment Ovaries are stimulates to release eggs by injection of hormones Eggs are retrieved and placed in fertilization container Sperm are added to fertilization container and left to fertilize eggs Fertilized eggs are left to grow into embryos One or two embryos are selected to be transferred to uterus of woman 10. What does the term mutation mean? A sudden change in the DNA of an organism 11. What are the two causes of mutations? Radiation and Chemicals 12. Give three examples of mutations and state whether they are beneficial or detrimental Beneficial – resistance to antibiotics/toxins, fur colour (camouflage), ability to drink milk and others Detrimental – seedless grapes, fur colour (not camouflaged), cancer and others 13. What genetic disorder is caused by i) too many body chromosomes ii)having an extra X chromosome in a female and a male and iii) having only one X chromosome I – down syndrome II – Triplo X in female, Klinefelter’s syndrome in males III – Turner’s syndrome 14. What is the cause behind the above disorders? Draw a diagram showing how these can occur in an individual. 15. Rabbits are a pest in Australia. The rabbit proof fence was one attempt at controlling the spread of rabbits. What was the other? Introduction of myxomatosis; a disease which kills rabbits. 16. Describe why, after many generations, rabbits are now much more resistant to your answer to Q15. Some rabbits already carried genes which made them resistant to the disease. These rabbits had a better chance at surviving to reproduce and pass on these genes to their offspring than those that did not. Now a larger proportion of rabbits are resistant to the disease. Population 17. Show, using a graph how the population of rabbits would have changed over time, starting from just before the introduction of the control measure from Q15. Time 18. Provide one argument for, and one against GM foods. GM foods can help solve world hunger, improve the production of food, make better versions of what nature has provided GM foods are not ‘natural’, may do more harm than good, we cannot see the long term effects of changing the species. 19. What is meant by the term ‘genetic screening’ and how could it benefit parents? Genetic screening is the process of checking the DNA of an offspring at the early stages of development and removing those individuals with qualities not desired by the parents. This can benefit parents who have, or carry a disease that could be passed on to their offspring which reduces the quality of life. Parents can be certain their child is disease free, although at the expense of removing those offspring that do have the disease. 20. The above pedigree chart is for a dominant/recessive type of inheritance pattern. Is the shaded characteristic dominant or recessive? How can you tell? Recessive as individuals 8 and 9 cannot have a shaded child unless shaded is recessive. (or individuals 3 and 4) 21. using G and g for the alleles, what is the genotype of individuals 5, 10 and 13 5 – Gg, 10 – gg, 13 – Gg or GG 22. Determine the genotypic ratio for the predicted offspring of individuals 3 and 4. ¼ GG, 2/4 Gg, ¼ gg 23. Using a punnet square, determine the % chance of a married couple having a son. 2/4 XY = 50% chance of a son Planet Boop is filed with lush pink plants. There lives a population of Babbits (which look like a rabbit, but have a few differences). Babbits are mostly blue, but some Babbits are pink. Most have short necks, but some have elongated necks. They have looked this way for thousands of years. 24. Some Quolves (which look like wolves and eat Babbits) are introduced to the area the Babbits inhabit. How and why does the allele frequency change in the Babbit population? The pink allele will increase in frequency as pink Babbits will have better survival rates (camouflaged). 25. A flood washes away all the low lying pink grasses the Babbits generally eat. How and why does the allele frequency change in the Babbit population? The elongated neck allele will increase in frequency as longer necks allow for better survival rates (can eat taller plants). 26. A population of purely green Boths (which look like sloths) are also preyed upon by the introduced Quolves. Choose the most likely outcome of the Dares: They will die out due to being easy and slow moving prey 27. Explain why the other two choices will not occur. Mutations are random events that may be beneficial, detrimental or be neutral in their effect. Mutations must occur to increase the variation within the population before a change in environment. Natural selection is a guided process that chooses which variations survive. There is no variation in the green Boths so they will die out.