173 Exam 1

<p>By binding to substrates and stabilizing the transition state.</p> Signup and view all the answers

<p>They release energy and are spontaneous.</p> Signup and view all the answers

<p>Concentration of the enzyme.</p> Signup and view all the answers

<p>High substrate concentration has no effect on find time.</p> Signup and view all the answers

<p>Enzymes are a type of catalyst that is not consumed in the reaction.</p> Signup and view all the answers

<p>The oxidation of catechol into orthoquinone</p> Signup and view all the answers

<p>Cultural and language differences</p> Signup and view all the answers

<p>Using a spectrophotometer to monitor absorbance changes</p> Signup and view all the answers

<p>It increases the reaction rate until substrate is limiting</p> Signup and view all the answers

<p>It increases and then levels off</p> Signup and view all the answers

<p>Fastest</p> Signup and view all the answers

<p>Defense against insects and microbes</p> Signup and view all the answers

<p>Change in absorbance over time</p> Signup and view all the answers

<p>It is required for the reaction to occur.</p> Signup and view all the answers

<p>It can destabilize ionic bonds and denature the enzyme.</p> Signup and view all the answers

<p>Chelating agents like PTU.</p> Signup and view all the answers

<p>By fermenting fiber into simpler compounds.</p> Signup and view all the answers

<p>Competitive inhibitor.</p> Signup and view all the answers

<p>Large intestine (colon).</p> Signup and view all the answers

<p>Render the enzyme inactive.</p> Signup and view all the answers

<p>Cyanide reacts with multiple metal ions, potentially inhibiting the enzyme.</p> Signup and view all the answers

<p>The maximum rate of reaction when all active sites of the enzyme are filled</p> Signup and view all the answers

<p>The reaction rate increases, but will eventually level off.</p> Signup and view all the answers

<p>They compete with the substrate for the active site of the enzyme.</p> Signup and view all the answers

<p>The substrate concentration when the reaction rate is half of Vmax</p> Signup and view all the answers

<p>They assist enzymes in catalyzing biochemical reactions.</p> Signup and view all the answers

<p>They decrease Vmax.</p> Signup and view all the answers

<p>Vmax decreases when the substrate concentration is high.</p> Signup and view all the answers

<p>By comparing the reaction rates with and without the inhibitor.</p> Signup and view all the answers

<p>Hydrogen, CO2, and CH4</p> Signup and view all the answers

<p>To include fermentation byproducts in the sample</p> Signup and view all the answers

<p>Gut microbiome activity</p> Signup and view all the answers

<p>To preserve strains for long-term storage</p> Signup and view all the answers

<p>Denaturation</p> Signup and view all the answers

<p>The DNA is cooled and strands bind to primers</p> Signup and view all the answers

<p>Agarose gel</p> Signup and view all the answers

<p>Presence of methane-producing microbes</p> Signup and view all the answers

<p>Enzyme activity decreases significantly due to denaturation caused by high heat.</p> Signup and view all the answers

<p>The frozen and then thawed enzyme shows faster reaction rates compared to the boiled enzyme.</p> Signup and view all the answers

<p>Potassium arsenite disrupts disulfide bonds by reacting with adjacent sulfhydryl groups, affecting the enzyme's structure.</p> Signup and view all the answers

<p>Partial inhibition suggests PHBA may be a noncompetitive inhibitor, affecting reaction rates at varying substrate concentrations.</p> Signup and view all the answers

<p>By calculating percent inhibitions at varying substrate concentrations, one can determine the inhibition type.</p> Signup and view all the answers

<p>Maintaining temperature is crucial as enzymes have optimal temperature ranges; deviations can lead to denaturation.</p> Signup and view all the answers

<p>One should expect little or no inhibition in the arsenite-treated enzyme compared to the control.</p> Signup and view all the answers

<p>Experiments measuring reaction rates with varying concentrations of PHBA will clarify its impact on enzyme activity.</p> Signup and view all the answers

<p>The reaction rate levels off because the enzyme becomes saturated, and the substrate availability no longer affects the rate of reaction.</p> Signup and view all the answers

<p>A higher Vmax and lower Km indicate increased enzyme efficiency, meaning the enzyme reaches its maximum rate faster and requires less substrate to achieve half of Vmax.</p> Signup and view all the answers

<p>Competitive inhibitors bind to the active site of the enzyme, while noncompetitive inhibitors bind to an alternate site, altering the enzyme's conformation.</p> Signup and view all the answers

<p>By measuring the Vmax with and without the inhibitor; if Vmax changes, it's noncompetitive, whereas if it remains the same, it's competitive.</p> Signup and view all the answers

<p>Percent inhibition decreases at higher substrate concentrations for competitive inhibitors as more substrate alleviates the competition for the active site.</p> Signup and view all the answers

<p>Cofactors assist enzymes by facilitating biochemical reactions, often by stabilizing enzyme structures or substrates.</p> Signup and view all the answers

<p>Hydrogen, CO2, and CH4.</p> Signup and view all the answers

<p>When the enzyme is saturated, increasing substrate concentration does not enhance enzyme activity; the reaction rate has reached its maximum.</p> Signup and view all the answers

<p>If Vmax remains unchanged, it indicates that the inhibitor competes with the substrate for the active site but does not affect the enzyme's maximum catalytic capability.</p> Signup and view all the answers

<p>The enzyme's reaction rate decreases in the presence of PTU, which reacts with copper, indicating that copper is essential for its activity.</p> Signup and view all the answers

<ol> <li>Denaturation, 2) Annealing, 3) Extension.</li> </ol> Signup and view all the answers

<p>Increasing salt concentrations can destabilize the ionic bonds that maintain the enzyme's proper conformation, ultimately leading to denaturation and decreased reaction rates.</p> Signup and view all the answers

<p>It classifies stool consistency and form, which is influenced by the activity and health of the gut microbiome.</p> Signup and view all the answers

<p>To prevent damage to bacterial cells during freezing and thawing processes.</p> Signup and view all the answers

<p>The gut microbiome ferments dietary fiber, breaking it down into simpler compounds, since humans lack the enzymes required for this process.</p> Signup and view all the answers

<p>At high substrate concentrations, the percent inhibition by competitive inhibitors is smaller because more substrate molecules outcompete the inhibitor for the active site.</p> Signup and view all the answers

<p>They diffuse into the bloodstream from the colon.</p> Signup and view all the answers

<p>It suggests healthier, better-formed stools.</p> Signup and view all the answers

<p>Chelating agents like PTU and potassium cyanide bind to metal ions, stripping them from the enzyme and significantly reducing its catalytic activity.</p> Signup and view all the answers

<p>Incubate the enzyme with various chelating agents, measure the reaction rates, and observe decreases when metal ions are stripped from the active site.</p> Signup and view all the answers

<p>The presence of methane-producing microbes in their gut microbiome.</p> Signup and view all the answers

<p>As salt concentration increases, the reaction rate of the enzyme decreases, indicating potential denaturation over time.</p> Signup and view all the answers

<p>Taq DNA polymerase synthesizes a new DNA strand by adding nucleotides to primers.</p> Signup and view all the answers

<p>The gut microbiome refers to all microbiomes present in the gut environment, primarily located in the large intestine or colon.</p> Signup and view all the answers

<p>Polyphenol oxidase activity increases at 45 degrees but slows down at 0 and 65 degrees.</p> Signup and view all the answers

<p>Absorbance measurement allows for monitoring the production of dark-colored products over time, indicating enzyme activity.</p> Signup and view all the answers

<p>Saturation occurs when increasing substrate concentration no longer increases the reaction rate as enzymes are fully utilized.</p> Signup and view all the answers

<p>Cultural and language differences can lead to misunderstandings or misinterpretations of scientific information.</p> Signup and view all the answers

<p>Catechol serves as the substrate that polyphenol oxidase oxidizes to form orthoquinone and the associated dark products.</p> Signup and view all the answers

<p>Non-competitive inhibitors decrease Vmax without affecting the enzyme's ability to bind to the substrate.</p> Signup and view all the answers

<p>Initial increases in enzyme concentration enhance reaction rate but level off when substrate becomes limiting.</p> Signup and view all the answers

<p>Lack of trust in scientific sources can prevent individuals from accepting valid scientific information.</p> Signup and view all the answers

<p>The enzyme begins to denature, resulting in a slower reaction or no reaction at all.</p> Signup and view all the answers

<p>It's crucial because water has a high specific heat, and it takes time for it to change temperature.</p> Signup and view all the answers

<p>The reaction rate of the frozen, then thawed enzyme is faster than that of the boiled, then cooled enzyme.</p> Signup and view all the answers

<p>Potassium arsenite disrupts disulfide bonds necessary for maintaining the tertiary structure of the protein.</p> Signup and view all the answers

<p>PHBA is expected to show partial inhibition of enzyme activity.</p> Signup and view all the answers

<p>By calculating the percent inhibitions at varying substrate concentrations, one can identify the type of inhibition.</p> Signup and view all the answers

<p>It implies that potassium arsenite is not an inhibitor of polyphenol oxidase.</p> Signup and view all the answers

<p>Calculating initial reaction rates helps quantify enzyme activity under specific conditions.</p> Signup and view all the answers

<p>Reaction rates level off because enzymes become saturated, limiting their ability to process additional substrate even as concentration increases.</p> Signup and view all the answers

<p>Higher Vmax indicates a greater maximum rate of reaction, demonstrating increased efficiency of the enzyme at processing substrates.</p> Signup and view all the answers

<p>A competitive inhibitor binds to the active site of an enzyme, preventing substrate binding, but does not change the Vmax of the reaction.</p> Signup and view all the answers

<p>A lower Km value indicates a higher affinity of the enzyme for its substrate, as it reaches half of Vmax at a lower concentration.</p> Signup and view all the answers

<p>By measuring the Vmax and analyzing if it changes; a decrease indicates a noncompetitive inhibitor, while no change indicates a competitive inhibitor.</p> Signup and view all the answers

<p>Cofactors assist enzymes in catalyzing reactions by stabilizing enzyme-substrate complexes or contributing to the active site’s architecture.</p> Signup and view all the answers

<p>Temperature affects enzyme activity by influencing reaction rates; an optimal temperature enhances activity, whereas extreme temperatures can denature enzymes.</p> Signup and view all the answers

<p>Percent inhibition quantifies the extent to which an inhibitor reduces enzyme activity, which varies with different substrate concentrations.</p> Signup and view all the answers

<p>Increasing salt concentration destabilizes ionic bonds in the enzyme, leading to denaturation and decreased reaction rates.</p> Signup and view all the answers

<p>Competitive inhibitors decrease enzyme activity by binding to the active site, preventing substrate from binding, especially at low substrate concentrations.</p> Signup and view all the answers

<p>Both PTU and potassium cyanide decrease the reaction rate of polyphenoloxidase by interacting with its copper cofactor.</p> Signup and view all the answers

<p>The gut microbiome ferments dietary fibers into simpler compounds such as short-chain fatty acids and gases like hydrogen.</p> Signup and view all the answers

<p>Chelating agents are significant because they strip metal ions from enzymes, allowing researchers to assess the role of these metal cofactors in enzymatic reactions.</p> Signup and view all the answers

<p>A positive control is a group expected to produce a desired effect, while a negative control does not receive the treatment and shows baseline conditions.</p> Signup and view all the answers

<p>Enzymes lower the activation energy barrier by stabilizing the transition state and orienting substrates appropriately.</p> Signup and view all the answers

<p>The gut microbiome breaks down complex carbohydrates (fiber) through fermentation, using specific enzymes produced by gut microbes.</p> Signup and view all the answers

<p>The copper cofactor is crucial for polyphenoloxidase activity as it facilitates oxidation reactions necessary for the enzyme's catalytic function.</p> Signup and view all the answers

<p>Increasing substrate concentration decreases find time due to more frequent collisions but does not affect processing time, which remains constant.</p> Signup and view all the answers

<p>At high substrate concentrations, the effect of a competitive inhibitor is minimized because the substrate can outcompete the inhibitor for the active site.</p> Signup and view all the answers

<p>A testable hypothesis allows for empirical validation through experiments, enabling scientists to confirm or refute their predictions.</p> Signup and view all the answers

<p>Binding to the substrate allows the enzyme to stabilize the transition state, which lowers the activation energy required for the reaction.</p> Signup and view all the answers

<p>A placebo serves as a negative control to determine the baseline effects without the active drug, allowing comparison of treatment efficacy.</p> Signup and view all the answers

<p>An enzyme acts as a catalyst by speeding up a reaction without being consumed in the process, thus facilitating metabolic pathways.</p> Signup and view all the answers

<p>Higher diffusion rates can increase the frequency of substrate-enzyme collisions, thus enhancing the enzyme's catalytic activity and increasing reaction rates.</p> Signup and view all the answers

<p>The main byproducts are hydrogen, carbon dioxide, and methane. They diffuse into the bloodstream and are eventually exhaled through the lungs.</p> Signup and view all the answers

<p>Collecting samples at the end ensures that the air contains fermentation byproducts, as early exhaled air may consist predominantly of respiratory gases.</p> Signup and view all the answers

<p>The Bristol stool score classifies stool into seven types based on shape and consistency, indicating that a higher diversity of microbiota often results in healthier stool forms.</p> Signup and view all the answers

<p>The steps are denaturation (DNA strands separate at ~98°C), annealing (primers bind at 50-65°C), and extension (DNA synthesis occurs at 72°C). Each cycle doubles the target DNA region.</p> Signup and view all the answers

<p>Cryoprotectants are added to prevent damage to bacteria during the freezing and thawing process, preserving their viability for long-term storage.</p> Signup and view all the answers

<p>Individuals who produce more methane generally possess a microbiome capable of using hydrogen to produce methane as a metabolic byproduct.</p> Signup and view all the answers

<p>Taq DNA polymerase synthesizes new DNA strands by adding nucleotides to primers, facilitating the amplification of target DNA sequences.</p> Signup and view all the answers

<p>The gut microbiome breaks down fiber, influencing water and nutrient absorption by producing short-chain fatty acids through fermentation.</p> Signup and view all the answers