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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.