Metabolism and Cellular Respiration, Exams of Nursing

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NVCC BIO 101 Exam 2 Metabolism - Answer- the totality of an organism's chemical reactions Metabolic pathway - Answer- Begins with a specific molecule, which is then altered in a series of defined steps, resulting in a certain product. catabolic pathway - Answer- release energy by breaking down complex molecules into simpler compounds anabolic pathways - Answer- consume energy to build complex molecules from simpler ones - proteins are synthesized from simpler molecules called amino acids Bioenergetics - Answer- the study of how energy flows through living organisms Energy - Answer- the capacity to cause change kinetic energy - Answer- energy of motion thermal energy - Answer- kinetic energy associated with the random movement of atoms or molecules heat - Answer- thermal energy in transfer from one object to another potential energy - Answer- energy that matter possesses because of its location or structure chemical energy - Answer- potential energy available for release in a chemical reaction Thermodynamics - Answer- The study of energy transformations that occur in a collection of matter. first law of thermodynamics - Answer- Energy can be transferred and transformed, but it cannot be created or destroyed - also called the principle of conservation of energy second law of thermodynamics - Answer- Every energy transfer or transformation increases the entropy of the universe. Entropy - Answer- - a measure of molecular disorder, or randomness - scientists use the term "disorder" to describe how dispersed energy is in a system and how many energy levels are present Chemical reactions - Answer- - Endergonic ("energy in") - Exergonic ("energy out") - Energy coupling Endergonic - Answer- - A chemical reaction that requires the input of energy in order to proceed - yields product rich in potential energy - start with reactabr molecules that contain relatively little potential energy but end with products that contain more chemical energy Exergonic - Answer- Chemical reactions that release energy - these reactions release the energy in covalent bonds of the reactants - burning wood releases the energy in glucose as heat and light energy coupling - Answer- The use of an exergonic process to drive an endergonic one. ATP (adenosine triphosphate) - Answer- main energy source that cells use for most of their work - composed of ribose (a sugar), adenine (a nitrous base), and a chain of three phosphate groups - ATP hydrolysis releases energy and produces ATP (adenosine diphosphate) and inorganic phosphate - the energy released comes from the chemical change to a state of lower free energy, not from the phosphate bonds themselves enzyme - Answer- A macromolecule serving as a catalyst, a chemical agent that changes the rate of a reaction without being consumed by the reaction. - most enzyme names end with -ase catalyst - Answer- substance that speeds up the rate of a chemical reaction activation energy - Answer- Energy needed to get a reaction started by breaking bonds in the reactant molecules A cell does three main kinds of work - Answer- chemical, transport, mechanical Substrate - Answer- the reactant molecule on which an enzyme acts - the enzyme binds to its substrate, forming an enzyme-substrate complex ATP - Answer- - is a renewable resource that is regenerated by addition of a phosphate group to ADP - the energy to phosphate ADP comes from catabolic reactions in the cell Stomata - Answer- Small openings on the underside of a leaf through which oxygen and carbon dioxide can move Chloroplast - Answer- composed of a double membrane surrounding a dense fluid called the stroma - a third membrane system, composed of sacs called thylakoids, is suspended within the stroma - the green in leaves comes from chlorophyll stages of photosynthesis - Answer- 1. Light-dependent Reaction: chlorophyll absorbs light energy to make carrier NADPH - H2O is split - O2 is released as a waste product - The electron acceptor NADP is reduced to NADPH - ATP is generated by adding a phosphate group to ADP in a process called photophosphorylation 2. Calvin cycle: Carbon Dioxide, ATP and NADPH are used to make glucose. - CO2 is initially incorporated into an organic molecule through a process called carbon fixation electromagnetic spectrum - Answer- All of the frequencies or wavelengths of electromagnetic radiation Wavelength - Answer- Horizontal distance between the crests or between the troughs of two adjacent waves Photons - Answer- particles of light - have a fixed quantity of light, inversely proportional to the wavelength of light pigment - Answer- Light-absorbing molecule - different pigments absorb different wavelengths light reactions - Answer- The first of two major stages in photosynthesis (preceding the Calvin cycle). These reactions, which occur on the thylakoid membranes of the chloroplast or on membranes of certain prokaryotes, convert solar energy to the chemical energy of ATP and NADPH, releasing oxygen in the process. Photosysten II - Answer- functions first (numbers reflect the order of discovery) and is best at absorbing a wavelength of 680 nm electron transfer chain - Answer- Array of enzymes and other molecules that accept and give up electrons in sequence, thus releasing the energy of the electrons in steps. Photosystem I - Answer- One of two light-harvesting units of a chloroplast's thylakoid membrane; it uses the P700 reaction-center chlorophyll. cellular respiration steps - Answer- 1. Glycolysis 2. Pyruvate Oxydation 3. Citric Acid Cycle (Krebs Cycle) 4. Oxidative Phosphorlyation Glycolysis - Answer- pyruvate: 2 ATP: 2 net NADH: 2 pyruvate oxidation - Answer- Acetyl CoA: 2 NADH: 2 CO2: 2 Citric Acid Cycle (Krebs Cycle) - Answer- CO2: 4 NADH: 6 ATP: 2 FADH2: 2 oxidative phosphorylation - Answer- ATP synthase uses energy from a proton gradient ATP: 28