Bio 110 Exam 3 Study Guide PDF

**[EXAM 3 STUDY GUIDE]** **[(cue the final countdown)]** Each student's exam will be unique. You are expected to complete the exam on your own without outside help. You **may** use your textbook, lecture notes, Canvas assignments, and lecture slides, but **NO GOOGLE SEARCHING. [Do not COPY/PASTE f...

**[EXAM 3 STUDY GUIDE]** **[(cue the final countdown)]** Each student's exam will be unique. You are expected to complete the exam on your own without outside help. You **may** use your textbook, lecture notes, Canvas assignments, and lecture slides, but **NO GOOGLE SEARCHING. [Do not COPY/PASTE from internet.]** I will be checking each answer for plagiarism. **If there is any content in your answer that is copied and pasted from the internet, you will receive a zero for that question**. **[PART I. Genetics]** 1\. Why is sexual reproduction advantageous, why is it disadvantageous? 2\. Do all sexually reproducing organisms have XY or XY chromosomes? Explain in depth. 3\. How do scientists think the Y chromosome evolved? 4\. Do the X and Y chromosomes cross over during meiosis? 5\. A mouse with a genotype of Bb and grey fur is mated with a mouse with a genotype of bb and white fur. What is the probability of the resulting offspring having white fur? 6\. A mouse with a genotype of BbCc and a phenotype of grey fur with black eyes is mated with a mouse with a genotype of bbcc and a phenotype of white fur and red eyes. What is the probability of the resulting offspring having white fur and black eyes? 7\. For each of the following pedigrees, label genotypes until you identify the inheritance pattern of the genetic disorder being portrayed by the black circles/squares. Explain how you know you are correct. A. Y Linked -- Michigan Genetics Resource Center B.  C. Autosomal Dominant Inheritance -- Michigan Genetics Resource Center D.  8\. Marie has Type O blood, and her sister has Type AB blood. The girls know that both of their maternal grandparents are Type A. (Note: Type O, Type AB, and Type A all are phenotypes.) What are the genotypes of the girls' parents? Draw a pedigree. 9\. **Genetic linkage** is the tendency of DNA sequences that are close together on a chromosome to be inherited together during the meiosis phase of sexual reproduction. Two genetic markers that are physically near to each other are unlikely to be separated onto different chromatids during "crossing-over" and are therefore said to be more ***linked* **than markers that are far apart. Recombination frequency (RF) is used to provide an estimate or approximation of physical distance of genes on a chromosome. \ [\$\$\\text{Recombination\~Frequency\~}\\left( \\text{RF} \\right)\\ = \\frac{\\text{Recombinants}}{\\text{Total\~Offspring}}x\\ 100\\%\$\$]{.math.display}\ *Which of the following gene pairs is most likely to be described as **linked**?* *(RF) A and B = 35.2%* *(RF) B and C = 12.5%* *(RF) C and D = 2.5%* *(RF) D and E = 42.7%* **[PART 2. DNA Replication and Transcription]** 1\. How are nucleotides bonded together to make a double-stranded DNA molecule? 2\. Where does the energy come from for forming phosphodiester bonds? 3\. Fill in the diagram by labeling each part and circle one nucleotide: 10\_05bAntiparallelDNA-U.jpg 4\. Why is DNA replication called semi-conservative? Draw the semi-conservative process. 5\. What bond type/s might be affected by a tautomeric shift? 6\. What might be the result of errors in DNA replication? 7\. What are the roles of single-stranded binding proteins? 8\. What are the roles of helicase and primase enzymes? 9\. For the following segment of DNA: 3' ATTTTACCGTATTACGACT 5' 5' TAAAATGGCATAATGCTGA 3' - What is the mRNA segment that would be transcribed? - What amino acids would this produce? - What would happen if there was a tautomeric shift causing a point mutation resulting in an adenine in position 7? What if it were in position 8? - What would happen if there were a deletion of the nucleotide in position 8? 10\. What is the only direction that nucleotides can be added to a polynucleotide chain by DNA polymerase? 11\. Which end of a nucleotide can RNA polymerase add nucleotides to a growing strand of mRNA? 12\. Which strand of DNA is always the template strand? 13\. What is the purpose of DNA replication? 14\. What is the purpose of transcription and translation? 15\. Define the following parts of a replication bubble: - Leading strand - Lagging strand - Okazaki fragments - Origin of replication - RNA primer - Topoisomerase - DNA polymerase - Ligase 16\. The Canary Islands are seven islands just west of the African continent. The islands gradually became colonized with life: plants, lizards, birds, etc. Three different species of lizards are found on the islands. These three species are similar to one species found on the African continent. Scientists think that the lizards traveled from Africa to the Canary Islands by floating on tree trunks washed out to sea. Where did the variation in body size of the three species probably [first] come from? A. The lizards needed to change in order to survive, so new helpful traits formed. B. Random changes in the DNA created new traits. C. The environment of the island caused certain changes in the DNA of the lizards. D. The lizards changed a little bit during each lizard's lifetime, and those traits were passed on to following generations. 17\. What is the Central Dogma? Explain in detail how gene products are made from genes. 18\. Compare mRNA and tRNA. 19\. What are the steps of transcription? 20\. What are the steps of translation? 21\. What post-transcriptional modifications take place to mRNA before it leaves the nucleus? 22\. Where is the site of translation? **[PART 3. Regulation of Gene Expression]** 1\. In what type of organism is the lac operon present? 2\. What is the default state of the lac operon and why? 3\. In your own words, explain the lac operon using the following terms: **Lactose, Regulatory Genes, Operator, Repressor, Promoter, RNA Polymerase, Lactose-utilization Genes (and what they do), Transcription Factor, Glucose**. 4\. Explain 7 ways that gene expression can be regulated. 5\. Dogs (humankind's BFF) begin life as a zygote with 78 chromosomes. The zygote begins to divide by making exact copies of its DNA until they become an adult dog with many cells. Provide a detailed answer to explain how a dog's retinal cells can be structured differently than its intestinal cells using the same DNA in every cell. (4-5 sentences) 6\. What is cell differentiation? 7\. What is the difference between embryonic and adult stem cells? 8\. What are induced pluripotent stem cells? 9\. Using the detail from lecture, explain where CRISPR-Cas9 technology came from, what it can be used for, and how it works. 10\. How can hormones such as insulin and human growth hormone be produced using gene technology? 11\. Explain in great detail the emergence of antibiotic resistance. How do bacteria become resistant/acquire resistance genes? 12\. Humans can only transfer genes by sexual reproduction or by using gene technologies like CRISPR-Cas9. Explain the different ways that prokaryotes like bacteria can transfer genes. How does this impact the evolution of antibiotic resistance? 13\. Explain the method discussed in lecture for identifying whether isolated bacteria are susceptible or resistant to antibiotics. **[PART 5. Immunology]** 1\. Explain how vaccines prevent severe infections in individuals. 2\. Explain how vaccinating healthy individuals protects immunocompromised individuals.  3\. How does innate immunity protect our bodies from pathogens? 4\. How does adaptive immunity protect our bodies from pathogens? (Make sure you understand B cells, antibodies, and T cells.)