BIO 2250 Exam #2 Study Guide PDF

BIO 2250 Exam #2 Study Guide Chapter 8: Control of Gene Expression 1. Why different cell types arise from the same genome: - The genome carries the complete set of instructions, but different cell types are formed through selective gene expression. Each cell type expresses only a specific subs...

BIO 2250 Exam #2 Study Guide Chapter 8: Control of Gene Expression 1. Why different cell types arise from the same genome: - The genome carries the complete set of instructions, but different cell types are formed through selective gene expression. Each cell type expresses only a specific subset of genes based on regulatory factors. 2. Stages of gene regulation: - Most common and easiest stage for regulation: Transcription. Regulating gene expression at the transcription level is the most efficient since it prevents unnecessary downstream processing. 3. Differentiation of cells: - Differentiation is controlled by regulatory proteins, which activate tissue-specific genes, driving cells to specialized states. 4. Three minimum transcription factors for iPS cells: - Oct4, Sox2, and Klf4 are sufficient to reprogram differentiated cells into pluripotent stem cells. Chapter 10: Analyzing the Structure and Function of Genes 1. Key Technologies: - PCR: Amplifies specific DNA sequences, crucial for molecular cloning and diagnostics (e.g., detecting pathogens). - Sanger Sequencing: Uses dideoxynucleotides to terminate DNA synthesis, creating fragments that can be sequenced to determine nucleotide order.  - Restriction Enzymes: Enzymes that cut DNA at specific sites, allowing scientists to construct recombinant plasmids. 2. Reporter Gene Assay: - Reporter genes are linked to regulatory sequences of interest to monitor gene expression. A common reporter is GFP, which fluoresces under certain conditions. Chapter 13: How Cells Obtain Energy from Food 1. Where is most ATP generated? - Mitochondria, through oxidative phosphorylation. 2. Location of three steps in glucose catabolism: - Glycolysis: Cytosol. - Pyruvate to Acetyl-CoA conversion: Mitochondrial matrix. - TCA Cycle: Mitochondrial matrix. 3. Fermentation (Muscle vs. Yeast): - Muscle: Pyruvate is reduced to lactate, producing 2 ATP per glucose. - Yeast: Pyruvate is converted to ethanol and CO2, also producing 2 ATP per glucose. 4. b-Oxidation and energy from fatty acids: - Fatty acids are broken down to produce acetyl-CoA, which enters the TCA cycle for energy production. Each cycle of b-oxidation generates multiple acetyl-CoA molecules. 5. Amino acids in the TCA cycle: - Amino acids can be converted to intermediates that enter the TCA cycle for energy production. Chapter 14: Energy Generation in Mitochondria and Chloroplasts 1. Proton Gradient: - A proton gradient is established across the mitochondrial inner membrane during the electron transport chain, driving ATP synthesis. 2. What enzyme produces ATP? - ATP synthase, driven by the proton gradient, synthesizes ATP during oxidative phosphorylation. 3. Structure of mitochondria and chloroplasts: - Mitochondria: Double membrane, with the inner membrane folded into cristae. - Chloroplasts: Contain thylakoid membranes (site of light reactions) and stroma (site of the Calvin cycle). 4. More mitochondria in energy-consuming cells: - Muscle and sperm cells contain more mitochondria due to high energy demands. 5. Role of Acetyl-CoA: - Acetyl-CoA is a central metabolite in both catabolism (TCA cycle) and anabolism (lipid biosynthesis). 6. Oxygen's role in energy production: - Oxygen is the final electron acceptor in the electron transport chain, allowing for efficient ATP production. 7. Difference between mitochondria and chloroplasts (sending energy to cytosol): - In mitochondria, ATP is directly exported to the cytosol for cellular use, while in chloroplasts, ATP is used within the chloroplast to synthesize carbohydrates. 8. Order of Photosystems: - Photosystem II occurs first, producing O2 and ATP, followed by Photosystem I, which produces NADPH. 9. ATP and NADPH in the Calvin Cycle: - Each turn of the Calvin cycle consumes 9 ATP and 6 NADPH. 10. Calvin Cycle Product: - The main product is glyceraldehyde 3-phosphate (G3P), which is used to form glucose and other carbohydrates. Chapter 11: Membrane Structure 1. Naming of membrane organelles: - Organelles like the nucleus, ER, Golgi apparatus, and mitochondria are part of the membrane system. 2. Most common phospholipid species: - Phosphatidylcholine is the most abundant phospholipid in the cell membrane. 3. Role of cholesterol: - Cholesterol modulates membrane fluidity, providing stiffness to the membrane. 4. Lipid synthesis and membrane assembly: - Lipid synthesis occurs in the smooth ER, with enzymes like scramblase and flippase facilitating the distribution of lipids between membrane leaflets. 5. Orientation of the membrane (topology): - Membranes are asymmetric, with distinct lipid compositions on the inner and outer leaflets. 6. Types of membrane proteins and their functions: - Membrane proteins include transporters, anchors, receptors, and enzymes, each facilitating specific cellular functions. 7. Membrane association of proteins: - Proteins can be transmembrane (span the bilayer), lipid-linked, or protein-attached, with varying degrees of mobility within the membrane. 8. Dynamic nature of the membrane: - Membrane proteins and lipids can move laterally, contributing to the fluidity of the membrane. 9. Lateral mobility restrictions: - Membrane protein mobility can be restricted by tight junctions, anchoring proteins, or interactions with the cytoskeleton. 10. Membrane protein modification (glycosylation): - Proteins can be glycosylated, meaning sugars are covalently attached, playing a role in cell recognition and signaling.