BIO 1124 EXAM 3 QUESTIONS AND WELL ELABORATED SOLUTIONS VERIFIED 100% CORRECT

BIO 1124 EXAM 3 QUESTIONS AND WELL ELABORATED SOLUTIONS VERIFIED 100% CORRECT Exergonic reaction - ANSWER -A spontaneous chemical reaction in which there is a net release of energy Endergonic reaction - ANSWER -A non-spontaneous chemical reaction in which free energy is consumed from the surroundings Enzyme - ANSWER -Proteins that regulate metabolism and aren't consumed by the reaction Active site of enzyme - ANSWER -Specific region of an enzyme that binds to the substrate What is the definition of a catalyst? - ANSWER -Chemical agents that speed up chemical reactions, but are not consumed by the reaction In what way is an enzyme a catalyst? - ANSWER -They regulate the rate of metabolism and thus speed up certain chemical reactions In what way are enzymes very specific in function? - ANSWER Enzymes only bind to certain substrates and thus regulate a specific part of a metabolic pathway Why are enzymes highly specific? - ANSWER -An enzyme's active site will only bind to a certain type of substrate How many different enzymes are typically found in a cell? - ANSWER -Thousands of different enzymes How do metabolic pathways work? (for example, the breakdown of glucose to pyruvate) - ANSWER -A starting molecule (glucose) is modified by a certain enzyme; this new product is modified by a different enzyme; repeats until you get pyruvate How do anabolic and catabolic pathways differ? - ANSWER -Catabolic pathways release energy while anabolic pathways consume energy What are coupled reactions in a metabolic pathway? - ANSWER Energy consuming reactions (anabolic) are coupled with energy releasing reactions (catabolic) e.x. Breakdown of ATPADP (catabolic) coupled with a phosphate group being attached to glucose (anabolic) Draw and label the enzyme sucrase and its hydrolysis of sucrose - ANSWER - ATP - ANSWER -Adenosine tri-phosphate Major energy currency in a cell What are the three main kinds of work that cells perform? - ANSWER Chemical work - endergonic reactions that build complex molecules Transport work - Pumping substances across membranes against their concentration gradients Mechanical work - Beating cilia, muscle cell contraction, movement of chromosomes during cell division How does ATP perform cell work? - ANSWER -ATP phosphorylates (attaches a phosphate group) a reactant, causing it to be less stable and have higher free energy Allows the next step in a metabolic pathway to be more energetically favorable Phosphorylated intermediate - ANSWER -Reactant with a phosphate group attached by ATP hydrolysis More reactive (higher free energy, less stable) Draw and label the process of glutamic acid + ammonia to get glutamate - ANSWER - Draw and annotate an ATP molecule - ANSWER - Energy of activation - ANSWER -The amount of energy reactants must absorb before a chemical reaction will start E.x. match added to can of gasoline Enzyme Cofactor - ANSWER -Non-protein helpers that assist enzymes in catalyzing reactions May be tightly or loosely bound to the enzyme E.x. zinc, copper, iron Coenzyme - ANSWER -An organic cofactor E.x. vitamins How is ATP regenerated? - ANSWER -A phosphate group is reattached to ADP, creating ATP Requires energy from catabolism (e.x. cellular respiration)