Q1a. What is the difference between a catabolic and an anabolic process?

Background

Topic: Metabolism – Catabolism vs. Anabolism

This question tests your understanding of the two main types of metabolic pathways in cells: catabolic and anabolic processes.

Key Terms:

• Catabolic process: Pathways that break down molecules, releasing energy.

• Anabolic process: Pathways that build complex molecules from simpler ones, requiring energy input.

Step-by-Step Guidance

1. Define what a catabolic process is and give a common example (e.g., cellular respiration).

2. Define what an anabolic process is and give a common example (e.g., protein synthesis).

3. Compare the direction of energy flow in each process (does it release or require energy?).

4. Think about how these processes are related in the cell’s overall metabolism.

Try explaining the difference in your own words before checking the answer!

Q1b. What is the difference between kinetic and potential energy?

Background

Topic: Energy Types in Biology

This question is about distinguishing between two fundamental forms of energy relevant to biological systems.

Key Terms:

• Kinetic energy: Energy of motion.

• Potential energy: Stored energy due to position or structure.

Step-by-Step Guidance

1. Define kinetic energy and provide a biological example (e.g., movement of molecules).

2. Define potential energy and provide a biological example (e.g., energy stored in chemical bonds).

3. Consider how energy can be transformed from one form to another in living organisms.

Try to come up with your own examples before revealing the answer!

Q1c. What is the difference between endergonic and exergonic reactions? (Also, positive vs. negative )

Background

Topic: Free Energy Changes in Chemical Reactions

This question tests your understanding of how energy changes during chemical reactions and how to interpret (Gibbs free energy change).

Key Terms and Formulas:

• Endergonic reaction: Requires energy input;

• Exergonic reaction: Releases energy;

• Gibbs free energy change:

Step-by-Step Guidance

1. Recall the definition of and what it means for a reaction to have a positive or negative value.

2. Define endergonic and exergonic reactions in terms of energy flow and .

3. Think about whether these reactions are spontaneous or require energy input.

4. Relate these concepts to biological processes (e.g., ATP hydrolysis is exergonic).

Try classifying a reaction as endergonic or exergonic based on before checking the answer!

Q1d. What is the difference between oxidized and reduced molecules?

Background

Topic: Redox Reactions in Biology

This question is about understanding oxidation and reduction, which are key in cellular respiration and photosynthesis.

Key Terms:

• Oxidation: Loss of electrons (or hydrogen atoms).

• Reduction: Gain of electrons (or hydrogen atoms).

Step-by-Step Guidance

1. Define what it means for a molecule to be oxidized and what it means to be reduced.

2. Remember the mnemonic "OIL RIG" (Oxidation Is Loss, Reduction Is Gain of electrons).

3. Think of a biological example (e.g., NAD+ being reduced to NADH).

4. Consider how these processes are coupled in metabolism.

Try to write your own example of oxidation and reduction before revealing the answer!

Q2. Can energy be created or destroyed? If not, describe what it does instead when flowing through an organism or ecosystem.

Background

Topic: Laws of Thermodynamics in Biology

This question tests your understanding of the first law of thermodynamics and how energy is transferred in biological systems.

Key Terms:

• First Law of Thermodynamics: Energy cannot be created or destroyed, only transformed or transferred.

• Energy flow: Movement of energy through organisms and ecosystems, often changing form.

Step-by-Step Guidance

1. State the first law of thermodynamics in your own words.

2. Describe how energy enters an ecosystem (e.g., sunlight) and how it is transferred between organisms.

3. Explain what happens to energy as it moves through trophic levels (e.g., some is lost as heat).

4. Think about why energy flow is not 100% efficient in biological systems.

Try to trace the path of energy through an ecosystem before checking the answer!

Q3. What are the four ways energy consumed by an organism was said to be used in the PowerPoint?

Background

Topic: Energy Utilization in Organisms

This question asks you to recall the main ways organisms use the energy they consume.

Key Terms:

• Energy for maintenance (e.g., homeostasis)

• Energy for growth

• Energy for reproduction

• Energy for activity (e.g., movement)

Step-by-Step Guidance

1. List the four main categories of energy use discussed in class or the PowerPoint.

2. Briefly describe what each category means in a biological context.

3. Think of examples for each type of energy use.

Try to recall all four uses before checking the answer!

Q4. What has more free energy, a molecule of ATP or a molecule of glucose? Explain.

Background

Topic: Free Energy in Biological Molecules

This question tests your understanding of the energy content of ATP and glucose, two key molecules in metabolism.

Key Terms:

• ATP (adenosine triphosphate): The cell’s main energy currency.

• Glucose: A simple sugar and major energy source for cells.

• Free energy (): The energy available to do work.

Step-by-Step Guidance

1. Recall the structure and function of ATP and glucose.

2. Think about which molecule stores more chemical energy overall.

3. Consider how many ATP molecules can be produced from one glucose molecule during cellular respiration.

4. Explain your reasoning based on the energy released during metabolism.

Try to reason through the comparison before checking the answer!

Q5. If a chemical reaction has , describe whether it is endergonic or exergonic, and whether energy is absorbed or released.

Background

Topic: Gibbs Free Energy and Reaction Types

This question asks you to interpret the sign and value of for a chemical reaction.

Key Terms and Formulas:

• Endergonic reaction: (energy absorbed)

• Exergonic reaction: (energy released)

Step-by-Step Guidance

1. Look at the sign of (is it positive or negative?).

2. Recall what a positive means for the reaction’s energy requirements.

3. Decide if the reaction is endergonic or exergonic based on the sign.

4. State whether energy is absorbed or released in this reaction.

Try to classify the reaction before checking the answer!

Q6. What is the activation energy () of a chemical reaction, and how does an enzyme affect ?

Background

Topic: Enzyme Catalysis and Activation Energy

This question is about understanding how enzymes speed up chemical reactions by affecting activation energy.

Key Terms and Formulas:

• Activation energy (): The minimum energy required to start a chemical reaction.

• Enzyme: A biological catalyst that lowers .

Step-by-Step Guidance

1. Define activation energy and its role in chemical reactions.

2. Explain how enzymes interact with reactants (substrates) to lower .

3. Describe the effect of lowering on the rate of reaction.

4. Think about why this is important for life processes.

Try to explain the effect of enzymes on before checking the answer!

Q7. What is the name of where the substrate binds to an enzyme?

Background

Topic: Enzyme Structure and Function

This question tests your knowledge of enzyme anatomy and how enzymes interact with substrates.

Key Terms:

• Substrate: The reactant that an enzyme acts on.

• Active site: The region on the enzyme where the substrate binds.

Step-by-Step Guidance

1. Recall the structure of an enzyme and where the substrate fits.

2. Identify the specific term for this region.

3. Think about how the shape of this region relates to enzyme specificity.

Try to recall the term before checking the answer!

Q8. After a chemical reaction, what happens to an enzyme? Is it used in the reaction?

Background

Topic: Enzyme Function and Reusability

This question is about what happens to enzymes after they catalyze a reaction.

Key Terms:

• Catalyst: A substance that speeds up a reaction without being consumed.

• Enzyme reusability: Enzymes are not used up in reactions.

Step-by-Step Guidance

1. Recall the definition of a catalyst and how it applies to enzymes.

2. Describe what happens to the enzyme’s structure after the reaction.

3. Explain whether the enzyme can be used again for another reaction.

Try to answer before checking the explanation!

Q9. What environmental variables affect enzyme activity?

Background

Topic: Enzyme Activity and Environmental Factors

This question asks you to recall the main factors that influence how well enzymes work.

Key Terms:

• Temperature

• pH

• Substrate concentration

• Presence of inhibitors or activators

Step-by-Step Guidance

1. List the main environmental factors that can affect enzyme activity.

2. Briefly describe how each factor can increase or decrease enzyme activity.

3. Think about what happens to enzyme structure under extreme conditions.

Try to list all the variables before checking the answer!

Q10. What are cofactors and enzyme inhibitors, and how do they affect enzyme activity?

Background

Topic: Enzyme Regulation

This question is about molecules that can help or hinder enzyme function.

Key Terms:

• Cofactor: A non-protein molecule or ion required for enzyme activity.

• Enzyme inhibitor: A molecule that decreases or stops enzyme activity.

Step-by-Step Guidance

1. Define what a cofactor is and give an example (e.g., metal ions, vitamins).

2. Define enzyme inhibitors and distinguish between competitive and noncompetitive inhibition.

3. Explain how cofactors and inhibitors affect the rate of enzyme-catalyzed reactions.

4. Think about why cells might regulate enzymes in these ways.

Try to explain the roles of cofactors and inhibitors before checking the answer!