Enzymes: Background and Pre-lab Assignment

Which equation summarizes the reaction being measured in the experiment examining catalase activity? 2H2O+catalase+2O2⟶4H2O2+heat2H2O+catalase+2O2⟶4H2O2+heat 2H2O+catalase+heat⟶2H2O2+O22H2O+catalase+heat⟶2H2O2+O2 H2O2+catalase+heat⟶2H2O+2O2H2O2+catalase+heat⟶2H2O+2O2 2H2O2+catalase⟶2H2O+O2+heat

2H2O2+catalase⟶2H2O+O2+heat

Enzymes are globular proteins that are critically important in many chemical reactions. Select the true statements about enzymes. -Enzymes can bind many different substrates. -Enzymes work best at extremely high temperatures. -Enzymes are not used up or changed during reactions. -Enzymes lower the activation energy needed for reactions. -Enzymes catalyze, or speed up, biochemical reactions.

Enzymes are not used up or changed during reactions. Enzymes lower the activation energy needed for reactions. Enzymes catalyze, or speed up, biochemical reactions.

Which statement is true about the active site present in enzymes? -The active site increases the rate of product formation. -The active site is irreversibly changed after one reaction. -After the enzymatic reaction, the active site is destroyed. -The active site of any enzyme can bind diverse molecules.

The active site increases the rate of product formation.

Please complete the sentence describing the reaction that will be observed in the simulation. This procedure involves observing how the enzyme ___________, affected the substrate, _________________ This reaction yields the products ___________________

catalase, hydrogen peroxide. water and oxygen.

Identify the three environmental factors that will be examined in the experiment examining catalase activity. substrate concentration enzyme concentration atmospheric oxygen level pH temperature

substrate concentration pH temperature

How will the enzyme activity be measured in the experiment? the amount of hydrogen peroxide produced changes in the amount of catalase present the amount of oxygen gas produced changes in solution pH from beginning to end

the amount of oxygen gas produced

How does the three‑dimensional shape of the enzyme impact enzymatic activity? -Changes in enzyme shape regulate the rate of the catalytic reaction. -Enzyme shape determines the type of substrate that binds the active site. -Changes in enzyme shape trigger release of the catalytic products. -Enzyme shape affects how many substrate molecules can bind at once.

-Enzyme shape determines the type of substrate that binds the active site. The three‑dimensional shape of an enzyme directly determines the specificity of the active site. Substrate molecules bind to the "pocket" of the enzyme called the active site, where they undergo the biochemical reaction necessary to convert substrate to products. If the three‑dimensional shape of an enzyme is changed, the likelihood of the active site no longer binding its particular substrate increases dramatically. When a substrate molecule binds an active site, the induced fit model suggests that the enzyme shape modifies slightly to better accomodate the substrate. These changes allow for better stability between the enzyme and the substrate and are completely reversible. When the products are released from the active site, the enzyme resumes its initial configuration in order to bind the next substrate molecule.

The specificity of an enzyme is determined by its three‑dimensional shape. Which environmental conditions can affect an enzyme's shape? -enzyme concentration -reaction time -pH -temperature -substrate concentration

pH temperature