GENETICS I. Review of DNA/RNA A. Basic Structure DNA 3 parts that make up a nucleotide 1. 2. 3. chains wrap around each other to form a Chains run in opposite direction known as Type of bond between the sugar and the phosphate group is known as Type of bond between bases B. Basic Structure RNA Thymine is replaced by # of strands Name of pentose (5C sugar) Leaves nucleus to travel to the Drawing/Fxn 3 types: mrna or trna or rrna or
C. DNA Replication List the main steps involved in DNA replication List the enzymes involved in DNA replication and identify their function
D. Protein Synthesis Transcription Translation DNA mrna Protein (polypeptide) (Nucleus) (Cytoplasm/ribosome)
II. TYPES OF INHERITANCE A. Simple Mendelian 1. Monohybrid Cross 2. Dihybrid Cross Probability: Odds of a black card = (A) Odds of an ace = (B) Odds of a black ace A x B = Define: 3. Law of Segregation 4. Law of Independent Assortment 5. Exception to above are linked genes (define as well) Define and give example of: B. Incomplete Dominance C. Co-Dominance D. Sex-Linked Trait (Typically, but not always, X-Linked)
E. Some Common Genetic Disorders: 1. Autosomal Recessive 2. Autosomal Dominant 3. Sex-Linked 4. Chromosomal III. Types of Mutations Point mutation Frameshift mutation Chromosomal mutation How is it tested for? Polyploidy Mutagens Teratogens Carcinogens Karyotype Pedigree
Modern Genetics Recombinant DNA Plasmid Restriction Endonucleases Blunt Cut (HaeIII) GGCC Restriction site between G & C GG CC CCGG CC GG Sticky Cut (HindIII) AAGCTT Restriction site between A & A A AGCT TTCGAA TTCGA A Transformation Vector (Importance of phages) Cloning Introns (Intragenic regions) Exons (Expressed regions) DNA Fingerprinting (Gel Electrophoresis)
1. During which meiotic phase are sister chromatids separated? a) Prophase I b) Metaphase I c) Metaphase II d) Anaphase I e) Anaphase II 2. One cell that undergoes meiosis will yield how many independent cells? a) 1 b) 2 c) 3 d) 4 e) 5 3. In which generation of a monohybrid cross do all the individuals look the same? a) Parental (P) b) F 1 c) F 2 d) F 3 4. In a monohybrid cross, the two parental genotypes are AA and aa. The genotype of all F 1 plants is Aa. If the F 1 plants are crossed to get an F 2 generation, what percentage of the F 2 generation will have the dominant phenotype? a) 0% b) 25% c) 50% d) 75% e) 100% 5. You are performing a dihybrid cross with two traits encoded by two different genes. These genes are on two different chromosomes and follow the Law of Independent Assortment. The two parental genotypes are AABB and aabb. The genotypes of all F 1 plants are AaBb. What phenotypic ration will you observe in the F 2 generation? a) 8:4:2:1 b) 1:1:1:1 c) 4:2:2:1 d) 1:2:2:1 e) 9:3:3:1
6. Tall is dominant over short; brown is dominant over green. The scientist wants to do a test cross to determine the genotype of a tall, brown F 1 hybrid. What will be the height and color of the other plant he uses in this test cross? a) Tall and brown b) Tall and green c) Short and brown d) Short and green e) It doesn't matter, any of the above will work 7. You are studying the inheritance of stem height and stem color. For height, tall is dominant over short and for color brown is dominant over green. You mate a purebred tall, brown plant to a purebred short, green plant and all of the F 1 offspring are tall and brown. You then mate two of these F 1 hybrid offspring together and count the following phenotypes in the F 2 offspring: 61 tall and brown; 1 tall and green; 2 short and brown; 18 short and green. Which of the following is probably true? a) The two genes controlling these traits are sex-linked b) The two genes controlling these traits might be on different chromosomes c) The two genes controlling these traits are linked with no crossing over d) The two genes controlling these traits are nearby on the same chromosome e) The two genes controlling these traits are far apart on the same chromosome 8. Which of the following is usually NOT true of an autosomal recessive disease? a) Most people with the disease have parent who do not have the disease b) An equal number of males and females get the disease c) If both parent have the disease, 50% of their offspring will have the disease d) If both parents are heterozygous, 75% of their offspring will not get the disease e) The genes for the disease are not located on the sex chromosomes 9. A woman who is heterozygous for hemophilia marries a man who has hemophilia. What percentage of their female offspring would you expect to have hemophilia? a) 0% d) 75% b) 25% e) 100% c) 50% 10. A boy with red-green color-blindness has a color-blind father and a mother who is not color-blind. From which parent did the boy inherit the color-blind allele? a) No way to know it could have been either one b) His father c) His mother d) It had to come partly from his mother and father e) It had nothing to do with either his mother or father
Refer to the pedigree below to answer Questions 11-14 11. Based on the chart, the allele causing the shaded trait is likely a) Codominant b) X-linked recessive c) Autosomal dominant d) Y-linked e) X-linked dominant 12. What is the probability that individual 3 is a carrier? a) 0% b) 25% c) 50% d) 75% e) 100% 13. What is the probability that individual 2 is a carrier? a) 0% b) 25% c) 50% d) 75% e) 100% 14. In order for #4 to have a son expressing the phenotype, he could mate with I. A female carrier II. An affected female III. A non-carrier female a) I only b) II only c) III only d) I and II only e) I, II and III
Refer to the following diagram to answer Questions 15-18 15. This transfer of genetic material is called a) Transcription b) Transduction c) Crossing-over d) Translation e) substitution 16. The depicted exchange of genetic material can occur during a) Prophase I of meiosis b) Anaphase I of meiosis c) Telophase of mitosis d) Metaphase II of meiosis e) Interphase of mitosis 17. After the chromosomes exchange material, which of the following could NOT result in the next generation? a) Adaptive mutation b) Same phenotype c) Debilitating mutation d) Change in diploid number e) Further transfers of genetic material 18. The exchange of genetic material only occurs in sexual reproduction, and offers a significant advantage over asexual reproduction. Why? a) Genetic recombination increases variation of species b) Random mutations are usually beneficial c) It alters the number of base pairs in the species' genetic code d) It increases reproduction rates e) It provides stability in the gene pool 1)c 2)d 3)b 4)d 5)e 6)d 7)c 8)c 9)c 10)c 11) b 12)c 13)c 14)d 15)c 16)a 17)b 18)a