Test On Enzymes! Knowledge Trivia Quiz

A substance that accelerates the rate of a chemical reaction is called a catalyst. A catalyst works by providing an alternative reaction pathway with a lower activation energy, allowing the reaction to occur more quickly. It does not get consumed in the reaction and can be used repeatedly. Lipids, molecules, and proteins are not specifically known for their ability to accelerate chemical reactions.

Without enzymes, the chemical reactions in the body would occur too slowly to support life processes. Enzymes act as catalysts, speeding up the rate of chemical reactions in the body. They lower the activation energy required for a reaction to occur, allowing it to happen more quickly. Without enzymes, the reactions would proceed at a much slower rate, which would not be sufficient to sustain the necessary life processes.

Activation energy is the term used to describe the energy required to initiate a chemical reaction. It represents the energy barrier that must be overcome for reactant molecules to transform into products. This energy is needed to break the existing bonds in the reactant molecules and start the formation of new bonds in the product molecules. Activation energy determines the rate at which a reaction occurs and is influenced by factors such as temperature, concentration, and catalysts.

All of the answer choices are correct because environmental factors such as temperature and pH can affect enzyme activity by altering the enzyme's shape and ability to bind to substrates. Cofactors, such as vitamins or metal ions, are necessary for some enzymes to function properly. Enzyme inhibitors can also affect enzyme activity by binding to the enzyme and preventing it from carrying out its normal function. Therefore, all of these factors can have an impact on enzyme activity.

A substrate is defined as a reactant that binds with an enzyme in order to facilitate and carry out a reaction. Enzymes have specific active sites where substrates bind, allowing the enzyme to catalyze the reaction. Therefore, the best definition for a substrate is a reactant that an enzyme binds with to carry out a reaction.

The statement "All enzymes have the same shape as their substrates" is not true. Enzymes have a specific three-dimensional shape, known as their tertiary structure, which allows them to bind to their substrates and catalyze chemical reactions. The shape of the enzyme's active site is complementary to the shape of its substrate, allowing for a specific and precise interaction. However, the shape of the enzyme itself is not the same as its substrate.

The active site of an enzyme is where the reactant fits into the enzyme. This is because enzymes are proteins that catalyze chemical reactions by binding to specific substrates at their active sites. The active site has a specific shape that allows it to bind with the reactant, forming an enzyme-substrate complex. This binding is essential for the enzyme to catalyze the reaction and facilitate the conversion of the reactant into the desired product. The specificity of the active site's shape ensures that enzymes can selectively bind to their specific substrates and carry out their biological functions effectively.

Enzymes act as catalysts in living cells, meaning they speed up chemical reactions without being consumed in the process. They achieve this by lowering the activation energy required for the reaction to occur. Therefore, enzymes directly affect the speed of the reaction, allowing it to occur more rapidly than it would without the enzyme. The other options, such as changing the products, temperature, or pH of the reaction, may indirectly influence the reaction speed but are not the primary role of enzymes in affecting reactions.

Enzymes are catalysts that speed up chemical reactions in the body. One of their characteristics is that they are specific, meaning they can only catalyze a particular reaction. They are also reusable, as they can be used over and over again in multiple reactions. Additionally, enzymes are not permanently changed during the reaction, meaning they can be used again for other reactions. Therefore, all of the given answer choices are correct in describing the characteristics of an enzyme.

Catalysts are substances that increase the rate of a chemical reaction by lowering the activation energy required for the reaction to occur. They do not slow down the rate of chemical reactions. Not all catalysts are enzymes, as enzymes are a specific type of catalyst found in living organisms. Catalysts are not used up during a chemical reaction, as they are not consumed in the reaction and can be reused. Therefore, the correct statement is that catalysts lower the activation energy of a chemical reaction.

The graph shows that reaction 2 has a higher activation energy barrier compared to reaction 3. This means that more energy is required for reaction 2 to proceed, resulting in a slower reaction rate. Therefore, the statement that "Reaction 2 occurs faster than reaction 3 because reaction 2 requires more energy than reaction 3" is incorrect. Instead, the correct statement is that the difference in the graphs is due to a difference in the activation energy needed for the two reactions.

Enzymes speed up chemical reactions by reducing the activation energy required for the reaction to occur. Activation energy is the energy needed to initiate a chemical reaction. By lowering this energy barrier, enzymes allow reactions to happen more easily and quickly. They do this by binding to the reactant molecules and bringing them closer together, facilitating the formation of new bonds and the breaking of existing ones. This lowers the energy required for the reaction to proceed, making it more efficient.

The graph suggests that reaction 3 occurred in the presence of a catalyst because it has a lower activation energy compared to reaction 2. A catalyst lowers the activation energy required for a reaction to occur, making it faster. The graph shows that reaction 3 has a lower activation energy than reaction 2, indicating that a catalyst was likely present.

The induced fit model of enzyme function suggests that substrate binding causes a slight change in the shape of the enzyme. This change allows for a better fit between the enzyme and the substrate, enhancing the efficiency of the catalytic reaction. This model emphasizes the dynamic nature of enzyme-substrate interactions, where the active site is not rigid but can adapt to accommodate the substrate. This flexibility ensures that the enzyme can effectively bind to and catalyze the reaction with the substrate.

Student 2's prediction is correct because enzymes are not depleted as a reaction progresses. Enzymes are catalysts that facilitate chemical reactions without being consumed in the process. They can be reused multiple times and remain unchanged at the end of the reaction. Therefore, the concentration of the enzyme in the test tube will stay the same as the reaction progresses.

When the pH in a stomach decreases, it means that the concentration of hydrogen ions (H+) is increasing. At the same time, the concentration of hydroxide ions (OH-) is decreasing. This is because a decrease in pH indicates an increase in acidity, which is caused by an increase in the concentration of H+ ions. The decrease in OH- ions is a result of the increase in H+ ions, as they combine to form water (H2O). Therefore, the correct answer is that H+ ions are increasing and OH- ions are decreasing.

When the pH in a stomach increases from 2 to 4, the hydrogen ion concentration decreases by a factor of 100. This is because pH is a measure of the concentration of hydrogen ions in a solution. As the pH increases, it indicates a decrease in the concentration of hydrogen ions. In this case, the increase in pH from 2 to 4 represents a decrease in the concentration of hydrogen ions by 100 times.