Q1. What are the components of the modern cell theory?

Background

Topic: Cell Theory

This question tests your understanding of the foundational principles that define what a cell is and how cells function as the basic unit of life.

Key Terms:

• Cell theory

• Organism

• Cell division

Step-by-Step Guidance

1. Recall the three main tenets of modern cell theory. Think about what they say regarding the structure, function, and origin of cells.

2. Consider how these tenets relate to all living organisms, not just animals or plants.

3. Reflect on how new cells are formed and what this implies about continuity of life.

4. Try to write out each component in your own words before checking the answer.

Try solving on your own before revealing the answer!

Q2. Describe in detail the major differences between prokaryotic and eukaryotic cells.

Background

Topic: Cell Types

This question tests your ability to distinguish between prokaryotic and eukaryotic cells based on their structural and functional characteristics.

Key Terms:

• Prokaryote

• Eukaryote

• Organelle

• Nucleus

Step-by-Step Guidance

1. Identify whether each cell type has a nucleus or not.

2. List the organelles present in eukaryotic cells and note which are absent in prokaryotic cells.

3. Consider the complexity and size differences between the two cell types.

4. Think about examples of organisms that have each cell type.

Try solving on your own before revealing the answer!

Q3. Describe the structure and function of mitochondria.

Background

Topic: Cell Organelles

This question tests your knowledge of the mitochondrion, its structural features, and its role in cellular energy production.

Key Terms:

• Mitochondria

• ATP

• Cellular respiration

Step-by-Step Guidance

1. Recall the main structural components of mitochondria (outer membrane, inner membrane, cristae, matrix).

2. Think about the function of each part, especially the inner membrane and its role in ATP production.

3. Consider how mitochondria are involved in cellular respiration and energy conversion.

4. Try to connect the structure to the function: why does the inner membrane have folds (cristae)?

Try solving on your own before revealing the answer!

Q4. Can you describe the concept of Gibbs' Free Energy? How is it expressed?

Background

Topic: Thermodynamics in Biology

This question tests your understanding of how energy changes in biological systems are quantified and predicted.

Key Terms and Formula:

• Gibbs Free Energy ()

• Enthalpy ()

• Entropy ()

• Temperature ()

Key formula:

Step-by-Step Guidance

1. Identify what each term in the formula represents: (change in free energy), (change in enthalpy), (temperature in Kelvin), (change in entropy).

2. Think about how this equation predicts whether a reaction is spontaneous or not.

3. Consider the biological significance: why is important for cellular processes?

4. Try to express the concept in your own words before checking the answer.

Try solving on your own before revealing the answer!

Q5. What are endergonic and exergonic reactions? Do they affect the free energy of a cell or system?

Background

Topic: Energy in Chemical Reactions

This question tests your understanding of how energy is absorbed or released during chemical reactions and how this relates to free energy changes.

Key Terms:

• Endergonic (enderthermic)

• Exergonic (exothermic)

• Free energy ()

Step-by-Step Guidance

1. Recall the definitions: endergonic reactions absorb energy, exergonic reactions release energy.

2. Connect these definitions to changes in (free energy).

3. Think about examples of each type of reaction in biological systems.

4. Consider how these reactions impact the energy balance of a cell.

Try solving on your own before revealing the answer!

Q6. What is ATP? Why is it important?

Background

Topic: Cellular Energy

This question tests your understanding of ATP's role as the energy currency of the cell.

Key Terms:

• ATP (Adenosine Triphosphate)

• Energy transfer

Step-by-Step Guidance

1. Recall the structure of ATP: three phosphate groups, ribose sugar, adenine base.

2. Think about how ATP stores energy in its phosphate bonds.

3. Consider why ATP is used for energy transfer in cells rather than other molecules.

4. Try to explain the importance of ATP in your own words before checking the answer.

Try solving on your own before revealing the answer!

Q7. What is a coenzyme? What is the function/role of coenzymes in metabolism?

Background

Topic: Enzyme Function

This question tests your understanding of how coenzymes assist enzymes in catalyzing metabolic reactions.

Key Terms:

• Coenzyme

• Enzyme

• Metabolism

Step-by-Step Guidance

1. Recall what a coenzyme is and how it differs from an enzyme.

2. Think about examples of coenzymes (NAD+, FAD, CoA).

3. Consider how coenzymes participate in metabolic reactions, especially in transferring electrons or functional groups.

4. Try to explain the role of coenzymes in your own words before checking the answer.

Try solving on your own before revealing the answer!

Q8. What are reduction and oxidation, and how are they coupled in biological systems?

Background

Topic: Redox Reactions in Biology

This question tests your understanding of electron transfer processes and their importance in metabolism.

Key Terms:

• Reduction

• Oxidation

• Redox reaction

Step-by-Step Guidance

1. Recall the definitions: oxidation is loss of electrons, reduction is gain of electrons.

2. Think about how these processes are always paired (one molecule is oxidized, another is reduced).

3. Consider examples in cellular respiration (NAD+ to NADH).

4. Try to explain how redox reactions drive energy transfer in cells.

Try solving on your own before revealing the answer!

Q9. What class of biological molecules are enzymes?

Background

Topic: Enzyme Structure

This question tests your knowledge of the molecular nature of enzymes.

Key Terms:

• Enzyme

• Protein

• Catalyst

Step-by-Step Guidance

1. Recall the four major classes of biological macromolecules.

2. Think about which class enzymes belong to and why.

3. Consider the structural features of enzymes that allow them to catalyze reactions.

Try solving on your own before revealing the answer!

Q10. How do enzymes and substrates interact?

Background

Topic: Enzyme-Substrate Interaction

This question tests your understanding of how enzymes recognize and bind substrates to catalyze reactions.

Key Terms:

• Enzyme

• Substrate

• Active site

Step-by-Step Guidance

1. Recall the concept of the active site on an enzyme.

2. Think about how substrate molecules fit into the active site (lock-and-key or induced fit models).

3. Consider what happens to the substrate during the interaction.

4. Try to explain the process in your own words before checking the answer.

Try solving on your own before revealing the answer!

Q11. How do enzymes increase the rate of chemical reactions?

Background

Topic: Enzyme Catalysis

This question tests your understanding of how enzymes lower activation energy to speed up reactions.

Key Terms:

• Activation energy

• Catalyst

• Transition state

Step-by-Step Guidance

1. Recall what activation energy is and why it matters for reaction rates.

2. Think about how enzymes stabilize the transition state and lower activation energy.

3. Consider the effect of this on the speed of reactions in cells.

4. Try to explain the mechanism in your own words before checking the answer.

Try solving on your own before revealing the answer!

Q12. What is activation energy, and how do enzymes lower it for a reaction?

Background

Topic: Enzyme Function

This question tests your understanding of the energy barrier in chemical reactions and the role of enzymes in overcoming it.

Key Terms:

• Activation energy ()

• Enzyme

• Transition state

Step-by-Step Guidance

1. Recall the definition of activation energy () as the minimum energy needed to start a reaction.

2. Think about how enzymes interact with substrates to lower this energy barrier.

3. Consider the effect of lowering activation energy on reaction rates.

4. Try to explain the process in your own words before checking the answer.

Try solving on your own before revealing the answer!

Q13. How is enzyme activity controlled/managed/regulated? What is ‘feedback’ inhibition, and what are the two different mechanisms discussed in class?

Background

Topic: Enzyme Regulation

This question tests your understanding of how cells regulate enzyme activity to maintain homeostasis.

Key Terms:

• Feedback inhibition

• Allosteric regulation

• Competitive inhibition

Step-by-Step Guidance

1. Recall what feedback inhibition is and why it is important for metabolic pathways.

2. Think about the two main mechanisms: competitive and allosteric inhibition.

3. Consider how each mechanism works to regulate enzyme activity.

4. Try to explain the differences between these mechanisms in your own words before checking the answer.

Try solving on your own before revealing the answer!

Q14. What is the purpose of cellular respiration? How does the ‘Crude Oil vs. Gasoline analogy’ apply to respiration (glucose → ATP)?

Background

Topic: Cellular Respiration

This question tests your understanding of why cells perform respiration and how energy is transformed.

Key Terms:

• Cellular respiration

• ATP

• Energy conversion

Step-by-Step Guidance

1. Recall the main goal of cellular respiration: converting glucose into usable energy (ATP).

2. Think about the analogy: crude oil is raw energy, gasoline is refined and usable.

3. Consider how glucose is processed to produce ATP, which cells can use directly.

4. Try to explain the analogy in your own words before checking the answer.

Try solving on your own before revealing the answer!

Q15. What are the three major pathways of aerobic respiration? What is the goal and end result of each part, and what is the net gain (ATP and NADH/FADH2) of each part?

Background

Topic: Aerobic Respiration

This question tests your understanding of the steps of aerobic respiration and their outcomes.

Key Terms:

• Glycolysis

• Krebs cycle (Citric Acid Cycle)

• Electron Transport System (ETS)

• ATP, NADH, FADH2

Step-by-Step Guidance

1. List the three main stages: glycolysis, Krebs cycle, and ETS.

2. For each stage, recall its location in the cell and its main purpose.

3. Think about the products of each stage (ATP, NADH, FADH2).

4. Try to summarize the net gain for each stage before checking the answer.

Try solving on your own before revealing the answer!

Q16. What happens (and where) to the six original carbons in the glucose molecule as it progresses through aerobic (and anaerobic) respiration?

Background

Topic: Carbon Fate in Respiration

This question tests your understanding of how glucose is broken down and what happens to its carbon atoms.

Key Terms:

• Glucose

• CO2

• Aerobic respiration

• Anaerobic respiration

Step-by-Step Guidance

1. Recall the structure of glucose (C6H12O6) and the number of carbon atoms.

2. Think about how glucose is split during glycolysis and further broken down in the Krebs cycle.

3. Consider where the carbon atoms end up (CO2, other molecules).

4. Try to trace the fate of each carbon atom through the process before checking the answer.

Try solving on your own before revealing the answer!

Q17. How do the ETS and chemiosmosis work to produce ATP in the mitochondria?

Background

Topic: Electron Transport and ATP Synthesis

This question tests your understanding of how the electron transport system and chemiosmosis generate ATP.

Key Terms:

• Electron Transport System (ETS)

• Chemiosmosis

• ATP Synthase

• Proton gradient

Step-by-Step Guidance

1. Recall how electrons from NADH and FADH2 are transferred through the ETS.

2. Think about how this transfer pumps protons (H+) across the inner mitochondrial membrane.

3. Consider how the resulting proton gradient drives ATP synthesis via ATP synthase.

4. Try to explain the process in your own words before checking the answer.

Try solving on your own before revealing the answer!

Q18. What is the role of oxygen in aerobic cellular respiration?

Background

Topic: Oxygen in Respiration

This question tests your understanding of why oxygen is essential for aerobic respiration.

Key Terms:

• Oxygen

• Electron acceptor

• ETS

Step-by-Step Guidance

1. Recall the final step of the electron transport system.

2. Think about what happens to electrons and protons at the end of ETS.

3. Consider why oxygen is needed for the process to continue.

4. Try to explain the role of oxygen in your own words before checking the answer.

Try solving on your own before revealing the answer!

Q19. Be able to discuss ATP output from the entire respiratory system.

Background

Topic: ATP Yield in Respiration

This question tests your ability to summarize the total ATP produced from aerobic respiration.

Key Terms:

• ATP

• Aerobic respiration

• Glycolysis, Krebs cycle, ETS

Step-by-Step Guidance

1. Recall the ATP produced in glycolysis, Krebs cycle, and ETS.

2. Think about how NADH and FADH2 contribute to ATP production in ETS.

3. Consider the total yield per glucose molecule.

4. Try to add up the ATP from each stage before checking the answer.

Try solving on your own before revealing the answer!