Bio 1113 OSU Exam 2 Questions And Answers Solutions Guaranteed

Photosynthesis - correct answers - Energy from sunlight powers biosynthesis of carbohydrates from inorganic materials - Ultimate source of food (energy) for all eukaryotic organisms Where does photosynthesis occur? - correct answers - Cytosol of prokaryotes - Chloroplasts of eukaryotes (chloroplasts are high structured, in plants 40-50 per cell) - Green color due to presence of chlorophyll pigments Who photosynthesizes? - correct answers - Autotrophs - Plants - Some protists (algae) - Some prokaryotes Light Energy - correct answers - Aka electromagnetic energy - Measured as wavelengths along an electromagnetic spectrum - Light in visible spectrum drives photosynthesis Light-Dependent Reactions: Photosystem 1 - correct answers - Antenna complex within struck by additional protons - Electrons (donated from the second one of these) are excited once again - Transferred down a 2nd ETC - NADP+ is final electron acceptor (reduced to NADPH) Calvin Cycle - correct answers - Calvin cycle used energy from light-dependent rxn to convert inorganic C to organic C (occurs in storm; input in atmospheric CO2; out put G3P 1 sugar) Calvin Cycle - Carbon Fixation - correct answers - Starts by "fixing" CO2 one at a time to a 5-C sugar, ribulose diphosphate (RuBP) -- Enzyme rubisco catalyzes rx that forms 6-C compound -- splits into two 3PGA molecules (3-C) Calvin Cycle - Regeneration - correct answers - RuBP is regenerated from five of the 3C compounds - 3 ATP are used 1. Fixation of carbon dioxide 2. Reduction of 3PGA to G3P 3. Regeneration of RuBP from G3P Calvin Cycle - Reduction - correct answers - Energy from ATP & NADPH is used to form G3P -- one is drawn off to form other organic molecules Why does photorespiration exist? - correct answers - Some evidence says its beneficial in other ways -- plays protective role in high-light, low CO2 environment C4 - correct answers Metabolic adaptation to concentrate CO2 Plasmodesmata - correct answers Plan cells; create gaps that connect cells -- plasma membrane & cell wall are continuous Gap Junctions - correct answers Open Channels Desmosomes - correct answers Provide extra support & resistance to tearing Tight Junctions - correct answers Create leak-proof seal Lipid-Soluble - correct answers Messengers diffuse into cytoplasm & interact directly w/receptors inside the cell Lipid-Insoluble - correct answers Messengers bind at cell surface and trigger signal transduction Telophase - correct answers - Nuclear envelope reforms - Chromosomes uncoil Anaphase - correct answers - Sister Chromatids are pulled apart Metaphase - correct answers - Chromosomes align on the metaphase plate (imaginary plate: a line equidistant form both poles/the centrosomes) Prometaphase - correct answers - Nuclear envelope disappears - Spindle Fibers "reach out" (a type of microtubule) Prophase - correct answers - Centrosomes migrate - Chromosomes condense Mitosis - correct answers - Division of the nucleus Cytokinesis - correct answers - Division of the cytoplasm Interphase - correct answers - 90% of the cell w/respect to time 2 types of defects in cancer cells - correct answers - Cell division proteins are activated when they shouldn't be - Tumor suppressor proteins do not properly shut down cell cycle Metastasis - correct answers Establishment of additional tumors elsewhere Alcohol Fermentation - correct answers - Occurs in some plants (Fungi, bacteria, and archaea) - 2 units ATP per glucose; NADH oxidized to NAD+ - Pyruvate is connected to acetylaldyde - CO2 and ethanol are waste products Lactic Acid Fermentation - correct answers - Occurs in animals when not enough O2 is delivered to cells - Each glucose molecule yield just 2 units of ATP - NADH donates electron directly to pyruvate - Lactate is a waste product Step 4: Electron transport and chemiosmosis - correct answers - In electron transport, electrons are (&H+) are transferred in series of redox runs - NADH & FADH2 are oxidized to NAD+ and FAD - Energy is released with each electron transfer - Oxygen is the final electron acceptor Step 3: Citric Acid Cycle - correct answers - Cycle of redox reactions - Regulated by feedback inhibitation Step 2: Pyruvate Processing - correct answers - Pyruvate enters mitochondrion, is converted to Acetyl-COA - 1 carbon (per pyruvate) is oxidized to CO2 - 1 NAD+ (per pyruvate) is reduced to NADH - Regulated by feedback inhibitation Step 1: Glycolosis - correct answers - A series of 10 rxns that oxidizes glucose to pyruvate - Starts w/an energy investments stage - Ends with energy extraction phase - Produces 2 pyruvate molecules - Net gain of 2 NADH + 2 ATP - Substrate-level phosphorylation generates ATP in glycolysis and the citric acid cycle - Enzyme catalyzes run that dephasphorylates a substrate and adds P to ADP Energy Comes From: - correct answers - Transfer of electrons - Transfer of phosphate group 2nd Law of Thermodynamics - correct answers Entropy will always increase in a system, when surroundings are taken into account Enthalpy (H) - correct answers Total energy of a molecule 1st Law of Thermodynamics - correct answers Energy is not created or destroyed; energy is only transferred from one type to another Cilia - correct answers Short, filament-like projections Flagella - correct answers - Long, hairlike projections - Eukaryotic of this made from micotubules Kinesin - correct answers (motor protein) pulls vesicles along microtubule "tracks" Intermediate Filaments - correct answers - Diverse group,