Fundamentals of Biochemistry: Metabolism, Enzymes, and Thermodynamics, Quizzes of Biology

Download Fundamentals of Biochemistry: Metabolism, Enzymes, and Thermodynamics and more Quizzes Biology in PDF only on Docsity! TERM 1 metabolism DEFINITION 1 -totality of an organisms chemical reactions-emergent property of life that arises from interactions between molecules within the cell-is NEVER at equilibrium (if it is... cell is dead) TERM 2 metabolic pathway DEFINITION 2 -begins with a specific molecule and ends with a product- each step is catalyzed by a specific enzyme TERM 3 catabolic pathway DEFINITION 3 -release energy by breaking down complex molecules into simpler compounds-EX: cellular respiration = breakdown of glucose in presence of oxygen to carbon dioxide and water TERM 4 anabolic pathways DEFINITION 4 -consume energy to build the complex molecules from the simpler ones-EX: synthesis of protein from amino acids TERM 5 bioenergentics DEFINITION 5 -study of how organisms manage their energy resources TERM 6 energy DEFINITION 6 -capacity to cause change-exists in various forms, some of which can perform work TERM 7 kinetic energy DEFINITION 7 -energy associated with motion TERM 8 heat (thermal energy) DEFINITION 8 -kinetic energy associated with random movement of atoms or molecules TERM 9 potential energy DEFINITION 9 -energy that matter possesses because of its location or structure TERM 10 chemical energy DEFINITION 10 -potential energy available for release in chemical reaction TERM 21 3 main kinds of work a cell does DEFINITION 21 -chemical-transport-mechanical TERM 22 energy coupling DEFINITION 22 -the use of an exergonic reaction to drive an endergonic reaction-this is how cells manage energy resources to perform work-most is mediated by ATP TERM 23 ATP (adenosine triphosphate) DEFINITION 23 -cell's energy shuttle-composed of ribose (a sugar), adenine (a nitrogenous base), and three phosphate groups-bonds between the phosphate groups can be broken by hydrolysis... this releases energy -> comes from the chemical change to a state of lower free energy, not from the phosphate bonds TERM 24 How does the hydrolysis of ATP perform work? DEFINITION 24 -mechanical, transport, and chemical work are powered by hydrolysis of ATP-the energy from the exergonic reaction of the ATP hydrolysis can be used to drive an endergonic reaction- overall, the coupled reactions are exergonic-ATP drives endergonic reactions by phosphorylation, transferring a phosphate group to some other molecule, such as a reactant-the recipient molecule is now called a phosphorylated intermediate TERM 25 phosphorylated intermediate DEFINITION 25 -a molecule with a phosphate group covalently bonded to it, making it more reactive (less stable) than the unphosphorylated molecule TERM 26 How does ATP regenerate? DEFINITION 26 -ATP is a renewable resource and is regenerated by the addition of a phosphate group to ADP-the energy to phosphorylate ADP comes from catabolic reactions in the cell-the ATP cycle TERM 27 DEFINITION 27 ATP CYCLE-energy released by breakdown reactions (catabolism) in the cell is used to phosphorylate ADP, regenerating ATP.-chemical potential energy stored in ATP drives most cellular workt TERM 28 enzyme DEFINITION 28 -macromolecule acting as catalyst (protein)EX of enzyme catalyzed reaction = hydrolysis of sucrose by the enzyme sucrose-catalyze reactions by lowering the activation energy barrier-speed up reactions that would occur eventually TERM 29 catalyst DEFINITION 29 -chemical agent speeding up reaction without being consumed by the reaction TERM 30 activation energy DEFINITION 30 -free energy of activation-the initial energy needed to start a chemical reaction-often supplied in the form of thermal energy that the reactant molecules absorb from their surroundings TERM 31 substrate DEFINITION 31 -the reactant an enzyme acts on-during reactions, is held in active site by weak interactions (i.e. hydrogen bonds & ionic bonds) TERM 32 enzyme-subtrate complex DEFINITION 32 -formed when the enzyme binds to the substrate-from here, the catalytic action of the enzyme converts the substrate to product or products of the reaction TERM 33 active site DEFINITION 33 -region on the enzyme where the substrate binds-can lower activation energy barrier by*orientating substrates correctly*straining substrate bonds*providing a favorable microenvironment*covalently bonding to the substrate TERM 34 induced fit DEFINITION 34 -brings chemical groups of the active site into positions that enhance their ability to catalyze the reaction TERM 35 What can an enzymes activity by affected by? DEFINITION 35 -general environmental factors such as temperature and pH- chemicals that specifically influence the enzyme