4. Energy _ Enzymes Presentation

Energy & Enzymes

• Theme: Energy and its transformations, cellular respiration, fermentation, and photosynthesis discussed throughout.

• Fun engagement with energy concepts through phrases like "DJ Enzyme" and meme references.

Course Objectives

• Objective #5: Compare and contrast:

  • Cellular respiration

  • Fermentation

  • Photosynthesis

  • Focus on overall reaction, stages, energy yield, and cellular location in prokaryotic and eukaryotic cells.

• Case Study: Why is Patrick paralyzed?

• Key Concepts of Energy:

  • Definition: The capacity to cause change

  • Types: Potential & Kinetic Energy

  • Laws of Thermodynamics

  • Reactions: Exergonic & Endergonic

• ATP: Acts as an energy intermediate.

• Enzymes: Role in catalysis, structure, and regulation.

• Metabolic Pathways: Overview to understand energy transactions in biological systems.

Characteristics of Life: OH GERMS

• Organized structures

• Homeostasis maintenance

• Growth and development

• Evolution through natural selection

• Reproduction capabilities

• Metabolism processes

• Sensitivity to the environment

Case Study: Why is Patrick Paralyzed?

• Background: Patrick's symptoms began at 16 with hand twitching.

• Gradual progression of weakness led him to the ER.

• Initial diagnosis pointed to demyelinating disease, no improvement after treatment over two years.

Diagnosis Exploration

• Q1: Potential causes for Patrick's paralysis:

  • A: Nervous system malfunction

  • B: Muscle dysfunction

  • C: Inefficient food breakdown for energy

  • D: All considered possibilities.

Energy Fundamentals

• Definition of energy: Capacity to instigate change; existing in numerous forms.

Energy Forms and Transformations

• Example with divers:

  • Potential Energy at height vs. Kinetic Energy during descent.

  • Energy transitions discussed based on height and motion.

Photosynthesis and Mitochondrial Energy Transformation

• Photosynthesis captures light energy and stores it as glucose (in covalent bonds).

• Mitochondria breakdown organic molecules to release stored energy.

Thermodynamics and Energy Flow in Life

• Study of Energy Transformations

  • Open Systems: Transfer of energy and matter.

  • Energy is introduced through light, exits as heat.

• First Law of Thermodynamics: Energy neither created nor destroyed, only transformed.

• Second Law of Thermodynamics: Energy transfer increases entropy (disorder), some energy is lost as heat.

Energy vs. Matter in Life Processes

• Q3: Key differences in energy and matter flow:

  • Matter is recycled; energy often converts to unusable forms.

  • Photosynthesis creates energy forms; matter flow predominantly increases.

Metabolic Processes in Cells

• Metabolism Types:

  • Anabolic: Builds complex molecules, requires energy (endergonic).

  • Catabolic: Breaks down molecules, releases energy (exergonic).

Exergonic Reactions

• Definition: Net release of free energy, enabling work capabilities.

  • Indicator: (∆G < 0), energy released during reactions.

Endergonic Reactions

• Definition: Absorbs energy from the surroundings.

  • Indicator: (∆G > 0), energy needed to proceed.

Energy Management in Cells

• Energy Coupling: Using exergonic reactions to drive endergonic processes.

• ATP's pivotal role in energy transfer.

ATP Overview

• Adenosine Tri-Phosphate (ATP): Energy carrier; importance highlighted.

• Key components include adenine, ribose, and phosphate groups.

Impact of ATP Depletion on Physiology

• Q4: Consequences of ATP loss for Patrick:

  • Muscle contraction failure.

  • Potential alternate energy sourcing.

  • Impaired electrical signal conduction by neurons.

Activation Energy and Catalysis

• Definition: Reactions need activation energy; facilitates bond breaking and formation.

• Activation Energy (EA) related to energy absorption dynamics.

Enzymatic Functionality

• Enzymes lower activation energy needed for reactions.

• They do not change the energy outcome of reactions but speed up processes.

Substrate Interaction with Enzymes

• Binding occurs at the active site to form enzyme-substrate complexes; conversion to product follows.

Mechanisms of Enzyme Action

• Induced Fit Model: Substrate binding induces enzyme conformational change.

• Enzymes are substrate-specific and reusable after reactions.

Metabolic Pathways Overview

• Sequential reactions where products of one serve as substrates for the next, catalyzed by different enzymes.

Influencing Factors on Enzyme Activity

• Cofactors: Ions like Fe+3 enhance reactions.

• Coenzymes: Organic molecules assisting without change from reactions.

• Temperature: Optimal around 37°C; pH varies but generally around 7.2.

Enzyme Characteristics and Inhibition

• Feedback Inhibition: End products can inhibit metabolic pathways to regulate resource use.

• Examples discussed in detail concerning the isoleucine synthesis pathway.

Biological Implications of Enzyme Inhibition

• Many insecticides inhibit enzymes permanently, prompting regulation due to potential risks.

Genetic Diseases Affecting Enzyme Function

• Patrick's enzyme mutation caused possible activity loss or regulation issues.

Effects of Specific Enzyme Inhibition

• Q6: Possible outcomes of inhibiting pyruvate to acetyl CoA conversion:

  • Increase of pyruvate; decrease of acetyl CoA and lactate levels.

Lactate Acidosis in Patrick

• Lactate and pyruvate buildup caused significant health issues.

• Symptoms detailed across several body systems (central, muscular, intestinal, respiratory, heart, gastric).

Patrick's Outcome

• Despite care, he succumbed to pneumonia and renal failure at a young age of 21 after years on life support.

• No current cure for lactate acidosis; treatments focus on buffering acidity.