Exam 2 Study Guide. Monday, July 30 th 125 points. 3 short answer questions approximately 7 points each

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1 Exam 2 Study Guide Monday, July 30 th 125 points 3 short answer questions approximately 7 points each No complete sentences required, though you can write them if you want Variable points (denoted next to the question) You may draw structures as needed 3 genetics problems 8 points each Recommended practice 22 multiple choice questions 2 points each Recommended self-quiz (skip 5, 10, and 12) 1 essay question 35 points Plus a couple points of extra credit Approximate chapter breakdown: 20% Lecture 7 Cell Communication 10% Lecture 8 Enzyme Energetics 20% Lecture 9 Cellular Respiration 20% Lecture 11 Cell Cycle 15% Lecture 12 Meiosis 15% Lecture 13 Mendel and the Gene Idea 10% Lecture 14 The Chromosomal Basis of Inheritance Example Questions 1. Which of the following statements describes the results of this reaction? C 6H 12O 6 + 6O 2 6CO 2 + 6H 2O + energy a. Glucose is oxidized and oxygen is reduced b. Oxygen is oxidized and water is reduced c. Carbon dioxide is reduced and oxygen is oxidized d. Glucose is reduced and carbon dioxide is oxidized 2. Which kind of metabolic poison would most directly interfere with glycolysis? a. An agent that reacts with oxygen and depletes its concentration in the cell b. An agent that binds to pyruvate and inactivates it c. An agent that closely mimics the structure of glucose but is unable to be metabolized d. An agent that reacts with NADH and oxidizes it to NAD+ 3. In a GPCR signal transduction cascade, what were to happen if you inhibit the action of adenylyl cyclase?

2 a. No camp would be produced, and protein kinase would not be activated b. GDP would not be phosphorylated into GTP, and G protein would be inactive c. The GPCR would be prevented from binding to G protein d. No ligand could bind to the GPCR e. The GPCRs would be unable to dimerize 4. You have lost about 15 pounds of fat on a regimen of strict diet and exercise. Congrats! How did the fat leave your body? a. It was converted to heat and released b. It was broken down into amino acids and released c. It was converted to feces and eliminated from the body d. It was released as carbon dioxide and water e. It was converted to ATP, which weighs less than fat 5. How many gametes can be produced by an organism with the genotype AaBbCCDdEE? a. 4 b. 8 c. 12 d. 16 e A triploid cell contains three sets of chromosomes. If a cell of a usually diploid species with 42 chromosomes per cell mutates and becomes triploid, the cell would be expected to have which of the following? a. 21 chromosome pairs and 21 unique chromosomes b. 63 chromosomes in 31.5 pairs c. 63 chromosomes in 3 sets of 21 d. 63 chromosomes, each with three sets of chromatids 7. Native strawberries are diploid. However, cultivated strawberries are usually octoploid (and sometimes even decaploid!) because polyploid fruits tend to be larger than their native cousins. Which of the following is true? a. Cultivated strawberries have been bred to have eight copies of their genome b. Cultivated strawberries tend to be much smaller than their native counterparts c. Cultivated strawberries have eight chromosomes versus two for their native counterparts d. Cultivated strawberries have eight pairs of chromosomes versus four for their native counterparts e. Cultivated strawberries are likely to be sterile 4. (Short answer) Why does anaerobic respiration yield so much less ATP than aerobic respiration? Include the terms electron transport chain, fermentation, glucose, and pyruvate. 5. (Short answer) Magnesium is an important cofactor in glucose-6-phosphatase. Glucose-6- phosphatase is an enzyme important in gluconeogenesis, the biochemical pathway by which glucose is built up. First, explain what a cofactor is, then explain what would happen if you got no magnesium in your diet. (Hint: humans produce starch in the form of glycogen). 6. (Short answer) The conversion of fructose-6-phosphate to fructose-1,6-bisphosphate through the enzyme phosphofructokinase is allosterically regulated by ATP. Considering the

3 overall result of glycolysis, would you expect ATP to inhibit or stimulate activity of phosphofructokinase? 7. (Short answer) Draw out and label each of the steps of meiosis for a diploid organism with a haploid number of four. 8. (Short answer) What is methylation, and how is it related to epigenetics? Use the terms euchromatin and heterochromatin, CpG islands, and gene regulatory regions. 9. (Short answer) Explain how adding a phosphate group triggers conformational change in a protein. 10. (Genetics) A couple goes to a genetic counselor, wondering about the possibility of their children inheriting X-linked colorblindness. The man is colorblind, but the woman is not. However, after further testing she finds she is heterozygous for colorblindness. What is the probability that: a. Their sixth child will be female b. Their female children will be colorblind c. Their male children will be colorblind Possible Essay Questions ½ to ¾ of a page 1. What is entropy? Explain it using the following terms: Exothermic and endothermic reactions Heat death of the universe Energy of activation, products, and reactants Open and closed systems Free energy 2. Explain how a GPCR works, starting from ligand binding and ending at cellular response. 3. Explain the process of glycolysis, the Krebs cycle, and the electron transport chain. Include the total inputs and outputs of each step, where each step takes place, and how energy flows through each step. You do NOT need individual names of enzymes and products/reactants except those listed below. Include the following terms: Glucose Potential energy, kinetic Acetyl-CoA energy Pyruvate oxidation ATP synthase, ATP NADH and FADH2 Electrochemical gradient 4. Describe the role of cyclins and Cdk in the cell cycle. Use the following terms: Checkpoints MPF G0, G1, G2, S phase Interphase, mitosis Oncogenes, tumor-suppressor genes

4 Study Guide for Exam 2 1 st law of thermodynamics 2 nd law of thermodynamics Entropy Energy of activation Energy coupling Endergonic, exergonic reactions Metabolism Catabolic, anabolic reactions Substrate Active site Competitive, noncompetitive inhibitors Allosteric Regulators Mechanism of action Rational drug design Cofactor, coenzyme 10nm fiber, 30nm fiber, beads on a string Model organisms Cyclins Cdk MPF G0, G1, G2, S phase Density-dependent inhibition Anchorage-dependent inhibition Apoptosis Roles of Ras and p53 in cancer Tumor-suppressor genes, oncogenes Somatic cell Germline cell Ligand, receptor Signal transduction pathway Phosphorylation cascade Conformational change Phosphorylation Residue GPCR, G protein RTK Ion-gated channels Phosphatases, kinases Second messengers camp, calcium ion Glycolysis Krebs/TCA cycle Redox reactions Terminal electron acceptor Chemiosmosis Oxidative phosphorylation Proton-motive force Fermentation Lactic acid fermentation Alcohol fermentation Obligate aerobes Facultative anaerobes Obligate anaerobes Definition of a gene Chromosome, chromatid Mitosis Meiosis I and II PPMAT Nondisjunction Kinetochore Centrosome Spindle Homozygous Heterozygous Epistasis Pleiotropy Incomplete dominance Codominance Polygenic inheritance X-linked traits Why men are more commonly affected by genetic disorders SRY gene Inheritance patterns in: o Hemophilia o Sickle cell anemia o Huntington s disease o Cystic fibrosis o Color blindness o Skin color

5 Sickle cell anemia providing resistance to malaria Aneuploidy Polyploidy X inactivation, Barr body Linked genes Linkage maps Deletion, duplication, inversion, and translocation in chromosomes Epigenetics How methylation creates euchromatin Heterochromatin, euchromatin