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quiz Cellular Respiration and photosynthesis
Overview of Energy Conversion
Energy conversion involves transforming light energy into cellular energy (ATP), essential for cellular functions such as growth and metabolism. Glucose breakdown releases energy for cellular activities.
Cellular Respiration
Cellular Respiration converts glucose into ATP and has two major types:
Aerobic Respiration: Requires oxygen, occurs in mitochondria, yielding more ATP.
Anaerobic Respiration: Occurs when oxygen is scarce, producing less ATP and includes processes like alcohol fermentation in yeast.
Mitochondria and ATP Production
Mitochondria are known as the powerhouse of cells, where ATP is primarily synthesized. ATP is crucial for assembling biological polymers, transporting materials, and supporting cell movement and reproduction.
the cyto[plasma in the mitochondria is called the matrix
Energy Flow in Ecosystems
Energy flows from producers (plants converting sunlight into chemical energy) to consumers (animals) and decomposers (microorganisms recycling nutrients).
Photosynthesis vs. Cellular Respiration
Cellular Respiration: C6H12O6 + O2 -> CO2 + H2O + ATP
Photosynthesis: H2O + CO2 + light energy -> C6H12O6 + O2 Both processes form a cyclical relationship sustaining life.
Catabolic Pathways
Catabolic pathways degrade larger molecules, like glucose, to release energy. Aerobic respiration yields more ATP than fermentation, which occurs under low oxygen conditions.
Glycolysis and Subsequent Steps
Glycolysis occurs in the cytoplasm, converting glucose to pyruvate and yielding 2 ATP. Pyruvate oxidation, the Krebs cycle, and the electron transport chain follow.
Oxidative Phosphorylation
Oxygen acts as the final electron acceptor, enabling high ATP yields (26-28 ATP per glucose) through the electron transport chain.
Fermentation Processes
Alcohol Fermentation: Occurs in yeast, converting pyruvate into ethanol and CO2.
Lactic Acid Fermentation: Occurs in muscle cells under low oxygen, converting pyruvate into lactic acid.
Importance of Electron Carriers
Electron carriers (NADH, FADH2) transport high-energy electrons to the electron transport chain, crucial for ATP production.
Overview of Photosynthesis
Photosynthesis is the process through which plants, algae, and some bacteria convert light energy into chemical energy (glucose) using carbon dioxide and water.
Key Concepts
Cellular Respiration Review
Process: Glucose (C6H12O6) + Oxygen → Carbon Dioxide + Water + Energy (ATP)
Type: Exergonic (energy is released)
Location: Mitochondria in eukaryotes; occurs in the cell membrane for bacteria.
ATP Production: More ATP produced via aerobic respiration (30-38 ATP) than fermentation (2 ATP).
Photosynthesis Definition
Equation: Carbon Dioxide + Water + Light Energy → Glucose + Oxygen
Type: Endergonic (energy is required to build glucose from smaller molecules).
Organelles: Occurs in chloroplasts in eukaryotic cells; in prokaryotes (like cyanobacteria), it occurs in the cytoplasm.
Roles of Producers and Consumers
Producers (Autotrophs): Organisms that make their own food using light (photoautotrophs).
Consumers (Heterotrophs): Organisms that obtain energy by consuming other organisms.
Decomposers: Break down dead material, returning nutrients to the environment.
Light Energy & Photosynthesis
Photon: The light energy captured by plants.
UV Radiation: Three types (UVA, UVB, UVC); UVA contributes to skin aging and skin cancer.
Plant Structure Related to Photosynthesis
Stomata: Openings on leaves for gas exchange (CO2 in, O2 out).
Chloroplasts Structure:
Outer and inner membranes.
Thylakoids: Folded membranes where light-dependent reactions occur.
contains proteins that are part of the electron transport chain
Stroma: Fluid surrounding thylakoids where light-independent reactions (Calvin Cycle) occur. (liquid portion of the chloroplasts)
Photosynthesis Phases
Light-Dependent Reactions:
Capture light energy and convert it to ATP and NADPH. (light energy and chemical energy)
Water is split to release electrons (oxidation) and produce oxygen.
electron transport chain/ chemosis
assists in light-independent
pumps out hydrogen proteins from the stroma into the thyolods
ATP synthase pumps out the hydrogen protons across the membrane, it produces ATP
Light-Independent Reactions (Calvin Cycle):
Use ATP and NADPH to convert CO2 into glucose.
Carbon fixation occurs via the enzyme Rubisco (combines CO2 with ribulose bisphosphate).
build bonds to generate glucose
going from a 1 carbon chain to a 6-carbon chin, which is an endergonic
electron transport chain creates ATP and NADPH, which are essential for the subsequent stages of photosynthesis, particularly in the Calvin cycle where glucose is synthesized.
Energy Coupling
Both cellular respiration and photosynthesis involve electron transport chains for ATP production.
Light-Dependent Reaction Products: ATP and NADPH.
Calvin Cycle Needs: Requires ATP and NADPH from the light-dependent reactions.
Important Terms
Carbon Fixation: Conversion of CO2 into organic compounds during the Calvin Cycle.
Rubisco: Enzyme that catalyzes the first step of the Calvin Cycle.
G3P (Glyceraldehyde 3 Phosphate): A three-carbon molecule produced that can be used to form glucose.
Environmental Impact
Increased CO2 from human activities (e.g., driving) affects climate change.
Trees and plants help mitigate CO2 levels, thus cutting them down exacerbates climate issues.
pumping hydrogen protein back into the matrix you’re making ATP
