Bio 101 NVCC Exam 2 QUESTIONS AND CORRECT ANSWERS ALREADY PASSED

Bio 101 NVCC Exam 2 QUESTIONS AND CORRECT ANSWERS ALREADY PASSED What is metabolism? - ANSWER the totality of an organism's chemical reactions What is a metabolic pathway? What is required in each step? - ANSWER is a series of chemical reactions which begins with a specific molecule and ends with a product Each step needs an enzyme What is difference between anabolic and catabolic pathways? - ANSWER Catabolic pathways-release energy by breaking down complex molecules into simpler compounds Anabolic pathways -consume energy to build complex molecules from simpler ones What is ATP molecule consists of? Why is it unstable? - ANSWER is composed of ribose (a sugar), adenine (a nitrogenous base), and three phosphate groupsThe triphosphate tail of ATP is the chemical equivalent of a compressed spring What is a catalyst? - ANSWER is a chemical agent that speeds up a reaction without being consumed by the reaction What are the three things required for any reaction to occur? - ANSWER How does an enzyme lowers the activation energy of the substrate? - ANSWER Enzyme can speed up a reaction by lowering the EA barrier without itself being consumed, also by right orientation of molecules. Which factors affect enzyme activity? - ANSWER temperature pH substrate concentration How competitive and non competitive inhibitors differ from each other? - ANSWER Competitive inhibitors bind to the active site of an enzyme, competing with the substrate Noncompetitive inhibitors bind to another part of an enzyme, causing the enzyme to change shape and making the active site less effective What are the examples of inhibitors? - ANSWER toxins, poisons, pesticides, and antibiotics What is a feedback inhibition? - ANSWER the end product of a metabolic pathway shuts down the pathway What are the laws of thermodynamics? - ANSWER the energy of the universe is constant, Every energy transfer or transformation increases the entropy (heat) of the universe, What are the parts of an enzyme? - ANSWER substrate, active site What is the difference between oxidation and reduction? - ANSWER In oxidation, a substance loses electrons, or is oxidized In reduction, a substance gains electrons, or is reduced (the amount of positive charge is reduced) What is the ultimate source of energy? - ANSWER sun What is phosphorylation? What are the three ways to make ATP? - ANSWER Light energy is converted to ATP when the electrons (oxidation) from chlorophyll pass through a system of carrier molecules Glycolysis, Citric Acid Cycle, Oxidative phosphorylation What are the endproducts of glycolysis? - ANSWER is 2 ATP plus 2 NADH per glucose molecule What are the products of citric acid cycle? - ANSWER 2 ATP, 6 NADH, 2 FADH2 What are the stages of cellular respiration? write a flow chart. - ANSWER Glycolysis> Aerobic respiration> The Krebs Cycle> The electron transport chain Which molecules act as electron carriers and bring the electrons to electron transport chain? - ANSWER What is the difference between fermentation and cellular respiration? - ANSWER Cellular Respiration- produces massive amounts of ATP, Needs oxygen, thought to be evolved after fermentaiton, final electron acceptor is oxygen Fermentation- Produces little ATP, No oxygen, came first, final electron acceptor is pyurvate What are the two types of fermentation? What are the products of fermentation? - ANSWER alcohol fermentationpyruvate is converted to ethanol lactic acid fermentation- pyruvate is reduced by NADH, forming lactate as an end product, with no release of CO2 Products: alcohol, carbon dioxide and lactic acid What are lipids and proteins broken down into? - ANSWER glucose and amino acids What is the difference between heterotrophs and autotrophs? Give example of each. - ANSWER Heterotrophs obtain their