Study Guide_ Photosynthesis and Cellular Respiration PDF

Study Guide: Photosynthesis and Cellular Respiration 1. Photosynthesis Photosynthesis is the process by which green plants, algae, and some bacteria convert light energy into chemical energy in glucose. This process occurs mainly in the chloroplasts of plant cells and involves the pigment chloroph...

Study Guide: Photosynthesis and Cellular Respiration 1. Photosynthesis Photosynthesis is the process by which green plants, algae, and some bacteria convert light energy into chemical energy in glucose. This process occurs mainly in the chloroplasts of plant cells and involves the pigment chlorophyll. Photosynthesis Equation: 6CO2​+6H2​O+light energy = ​C6​H12​O6​+6O2​ Reactants: Carbon dioxide (CO₂), Water (H₂O), and sunlight. Products: Glucose (C₆H₁₂O₆) and Oxygen (O₂). Stages of Photosynthesis: Photosynthesis occurs in two main stages: the Light-dependent reactions and the Calvin Cycle (Light-independent reactions). 1.1. Light-Dependent Reactions (Occur in the Thylakoid Membranes) This stage requires light to produce energy-rich compounds such as ATP and NADPH. It occurs in the thylakoid membranes of the chloroplasts. Inputs: 1. Light energy (from the sun) 2. Water (H₂O) 3. NADP⁺ 4. ADP + Pi Outputs: 1. ATP (Energy carrier) 2. NADPH (Electron carrier) 3. Oxygen (O₂) – released as a byproduct Process: 1. Photons hit the chlorophyll pigments, exciting electrons. 2. Water is split (photolysis) to provide electrons, releasing O₂ as a byproduct. 3. The electron transport chain (ETC) is activated, where excited electrons travel through proteins in the membrane. 4. Chemiosmosis generates ATP via ATP synthase. 5. Electrons are transferred to NADP⁺ to form NADPH. 1.2. Calvin Cycle (Light-Independent Reactions or Dark Reactions) The Calvin Cycle occurs in the stroma of the chloroplast and does not directly require light. It uses ATP and NADPH from the light reactions to fix carbon dioxide and synthesize glucose. Inputs: 1. Carbon dioxide (CO₂) 2. ATP 3. NADPH Outputs: 1. Glucose (C₆H₁₂O₆) 2. ADP + Pi 3. NADP⁺ Process: 1. Carbon Fixation: CO₂ is fixed into a 5-carbon molecule, ribulose bisphosphate (RuBP), by the enzyme Rubisco. 2. Reduction: ATP and NADPH are used to convert the fixed carbon into G3P (glyceraldehyde-3-phosphate), a 3-carbon sugar. 3. Regeneration: Some G3P molecules go on to form glucose, while others regenerate RuBP so the cycle can continue. 2. Cellular Respiration Cellular respiration is the process by which cells break down glucose (or other organic molecules) into usable energy (ATP). This process occurs in both plant and animal cells within the mitochondria. Cellular Respiration Equation: C6H12O6+6O2→6CO2+6H2O+ATP (energy)C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O + {ATP (energy)}C6​H12​O6​+6O2​→6CO2​+6H2​O+ATP (energy) Reactants: Glucose (C₆H₁₂O₆) and Oxygen (O₂). Products: Carbon dioxide (CO₂), Water (H₂O), and ATP. Stages of Cellular Respiration: Cellular respiration occurs in three main stages: Glycolysis, the Krebs Cycle (Citric Acid Cycle), and the Electron Transport Chain (ETC). 2.1. Glycolysis (Occurs in the Cytoplasm) Glycolysis is the first step of cellular respiration, and it breaks glucose into two molecules of pyruvate. It does not require oxygen (anaerobic). Inputs: 1. Glucose (C₆H₁₂O₆) 2. 2 NAD⁺ 3. 2 ADP + Pi Outputs: 1. 2 Pyruvate (C₃H₄O₃) 2. 2 NADH 3. 2 ATP (net gain) Process: 1. Glucose is split into two 3-carbon molecules. 2. ATP and NADH are produced through substrate-level phosphorylation. 2.2. Pyruvate Oxidation (Transition Step – Occurs in the Mitochondrial Matrix) After glycolysis, pyruvate is converted into acetyl-CoA to enter the Krebs Cycle. Inputs: ○ 2 Pyruvate ○ Coenzyme A ○ NAD⁺ Outputs: ○ 2 Acetyl-CoA ○ 2 NADH ○ 2 CO₂ (as waste) 2.3. Krebs Cycle (Citric Acid Cycle – Occurs in the Mitochondrial Matrix) The Krebs Cycle completes the breakdown of acetyl-CoA into CO₂, generating high-energy molecules. Inputs: 1. 2 Acetyl-CoA 2. NAD⁺, FAD 3. ADP + Pi Outputs: 1. 6 NADH 2. 2 FADH₂ 3. 2 ATP (through substrate-level phosphorylation) 4. 4 CO₂ (as waste)  Process: 1. Acetyl-CoA combines with a 4-carbon molecule (oxaloacetate) to form a 6-carbon molecule (citrate). 2. Citrate is broken down stepwise, releasing energy captured in NADH, FADH₂, and ATP. 3. The cycle regenerates oxaloacetate to continue the process. 2.4. Electron Transport Chain (ETC) and Chemiosmosis (Occurs in the Inner Mitochondrial Membrane) This stage generates the bulk of ATP by using NADH and FADH₂ to power the movement of electrons through a series of protein complexes, ultimately creating a proton gradient to produce ATP. Inputs: 1. NADH 2. FADH₂ 3. Oxygen (O₂) 4. ADP + Pi Outputs: 1. 32-34 ATP 2. Water (H₂O) Process: 1. Electrons from NADH and FADH₂ are passed along the ETC, losing energy at each step. 2. This energy pumps protons (H⁺) across the inner membrane, creating a proton gradient. 3. Protons flow back through ATP synthase, driving the synthesis of ATP. 4. Oxygen acts as the final electron acceptor, combining with protons and electrons to form water. Comparison of Photosynthesis and Cellular Respiration: Feature Photosynthesis Cellular Respiration Location Chloroplasts Mitochondria Reactants CO₂, H₂O, and C₆H₁₂O sunlight Study Guide: Photosynthesis, Cellular Respiration, and Biogeochemical Cycles 1. Photosynthesis Photosynthesis is the process by which plants, algae, and certain bacteria convert light energy into chemical energy stored in glucose. This occurs in the chloroplasts of plant cells, particularly within the pigment chlorophyll. Photosynthesis Equation: 6CO2+6H2O+light energy→chlorophyllC6H12O6+6O26CO_2 + 6H_2O + \text{light energy} \xrightarrow{\text{chlorophyll}} C_6H_{12}O_6 + 6O_26CO2​+6H2​O+light energychlorophyll​C6​H12​O6​+6O2​ Reactants: Carbon dioxide (CO₂), Water (H₂O), and light. Products: Glucose (C₆H₁₂O₆) and Oxygen (O₂). Stages of Photosynthesis: 1.1. Light-dependent Reactions (Photochemical Phase): Location: Thylakoid membranes of the chloroplasts. Inputs: Water (H₂O), sunlight, ADP, and NADP⁺. Outputs: Oxygen (O₂), ATP, and NADPH. Process: Light energy splits water molecules (photolysis) into oxygen, protons, and electrons. ATP and NADPH are produced as energy carriers to power the next stage. 1.2. Calvin Cycle (Light-independent Reactions or Dark Reactions): Location: Stroma of the chloroplasts. Inputs: Carbon dioxide (CO₂), ATP, and NADPH. Outputs: Glucose (C₆H₁₂O₆), ADP, NADP⁺. Process: Using the ATP and NADPH produced in the light-dependent reactions, CO₂ is fixed into glucose through a series of enzyme-catalyzed reactions. What happens in Photosynthesis inside plants? Energy Capture: Chlorophyll absorbs light energy, which drives the splitting of water molecules to release oxygen. Glucose Production: The plant uses the ATP and NADPH from the light-dependent reactions to convert carbon dioxide into glucose in the Calvin Cycle. This glucose is then used by the plant for growth, energy storage, and metabolism. 2. Cellular Respiration Cellular respiration is the process by which cells break down glucose to release energy in the form of ATP. This process occurs in the mitochondria of plant and animal cells. Cellular Respiration Equation: C6H12O6+6O2→6CO2+6H2O+Energy (ATP)C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O + \text{Energy (ATP)}C6​H12​O6​+6O2​→6CO2​+6H2​O+Energy (ATP) Reactants: Glucose (C₆H₁₂O₆) and Oxygen (O₂). Products: Carbon dioxide (CO₂), Water (H₂O), and ATP (Energy). Stages of Cellular Respiration: 2.1. Glycolysis: Location: Cytoplasm. Inputs: Glucose (C₆H₁₂O₆), 2 ATP. Outputs: 2 Pyruvate, 4 ATP (net gain of 2 ATP), and NADH. Process: Glucose is broken down into two molecules of pyruvate, producing a small amount of ATP and NADH. 2.2. Krebs Cycle (Citric Acid Cycle): Location: Mitochondrial matrix. Inputs: Pyruvate (converted into Acetyl-CoA), NAD⁺, FAD, ADP. Outputs: CO₂, ATP, NADH, and FADH₂. Process: Acetyl-CoA enters the cycle, producing CO₂, ATP, NADH, and FADH₂ (electron carriers). 2.3. Electron Transport Chain (ETC) and Oxidative Phosphorylation: Location: Inner mitochondrial membrane. Inputs: NADH, FADH₂, and O₂. Outputs: ATP (up to 34 molecules) and H₂O. Process: Electrons from NADH and FADH₂ travel through a chain of proteins, driving the production of ATP. Oxygen is the final electron acceptor, combining with protons to form water. What happens during Cellular Respiration inside plants? Energy Release: The glucose produced during photosynthesis is broken down in the mitochondria to release ATP, which the plant uses for various cellular functions. Oxygen Use: Oxygen, produced during photosynthesis, is consumed in the electron transport chain to generate ATP. 3. Biogeochemical Cycles 3.1. The Water Cycle The water cycle is the continuous movement of water on, above, and below the surface of the Earth. Evaporation: Water from oceans, lakes, and rivers turns into vapor. Condensation: Water vapor cools and condenses to form clouds. Precipitation: Water falls back to Earth as rain, snow, or other forms. Transpiration: Plants release water vapor from their leaves into the atmosphere. Runoff and Infiltration: Water flows over the surface or seeps into the ground, returning to water bodies. 3.2. The Carbon Cycle The carbon cycle involves the movement of carbon among the atmosphere, biosphere, oceans, and geosphere. Photosynthesis: Plants take in CO₂ and convert it into glucose. Respiration: Both plants and animals release CO₂ back into the atmosphere through cellular respiration. Decomposition: Decomposers break down dead organisms, releasing CO₂ into the atmosphere or storing carbon in the soil. Combustion: Burning of fossil fuels releases CO₂ into the atmosphere. 3.3. The Nitrogen Cycle The nitrogen cycle describes how nitrogen moves between the atmosphere, soil, and living organisms. Nitrogen Fixation: Nitrogen-fixing bacteria convert nitrogen gas (N₂) from the atmosphere into ammonia (NH₃) or nitrate (NO₃⁻) usable by plants. Nitrification: Bacteria in the soil convert ammonia into nitrites (NO₂⁻) and nitrates (NO₃⁻). Assimilation: Plants absorb nitrates and ammonia to build proteins and DNA. Ammonification: Decomposers convert dead organic matter back into ammonia. Denitrification: Bacteria convert nitrates back into nitrogen gas (N₂), returning it to the atmosphere. 4. Key Interactions in Photosynthesis and Cellular Respiration Carbon Cycling: Photosynthesis removes CO₂ from the atmosphere, while cellular respiration releases it back. Oxygen Cycling: Photosynthesis produces oxygen, which is used by plants and animals for cellular respiration, producing water and CO₂. Energy Flow: Light energy is captured by photosynthesis and stored as chemical energy in glucose. Cellular respiration releases this stored energy to power cellular functions. By understanding these cycles and processes, you gain insight into how energy is transferred through ecosystems and how organisms maintain balance with their environment. 1. ATP (Adenosine Triphosphate) Function: ATP is the primary energy carrier in cells, often called the "energy currency" of the cell. Structure: Composed of adenine (a nitrogenous base), ribose (a sugar), and three phosphate groups. Energy Release: When ATP is broken down into ADP (adenosine diphosphate) and inorganic phosphate (Pᵢ), energy is released to power cellular processes. Role in Photosynthesis: In the Light-dependent Reactions: ATP is produced in the thylakoid membrane of the chloroplasts using energy from sunlight. This ATP is used in the Calvin Cycle to synthesize glucose. Role in Cellular Respiration: Glycolysis: A small amount of ATP (net 2 molecules) is produced during the breakdown of glucose in the cytoplasm. Krebs Cycle and Electron Transport Chain (ETC): The majority of ATP is generated during the electron transport chain in the mitochondria (around 32-34 ATP molecules from one glucose molecule). 2. NADH (Nicotinamide Adenine Dinucleotide) Function: NADH is an electron carrier that transports high-energy electrons needed for producing ATP. It exists in two forms: NAD⁺ (oxidized) and NADH (reduced).  Energy Transport: NADH carries electrons to the electron transport chain (ETC), where it helps generate ATP through oxidative phosphorylation. Role in Photosynthesis: In the Light-dependent Reactions: A similar molecule, NADPH, is produced by the enzyme ferredoxin-NADP⁺ reductase. NADPH provides the reducing power needed to convert CO₂ into glucose during the Calvin Cycle. Role in Cellular Respiration: Glycolysis: NAD⁺ is reduced to NADH as glucose is broken down into pyruvate. Krebs Cycle: NADH is produced during the Krebs Cycle when pyruvate is further broken down, releasing electrons. Electron Transport Chain: NADH donates its electrons to the first protein complex in the ETC, leading to the production of ATP. 3. Pyruvates (Pyruvic Acid) Function: Pyruvate is the end product of glycolysis, which is the first step in breaking down glucose to extract energy. Structure: Pyruvate is a 3-carbon molecule (C₃H₄O₃). Role in Photosynthesis: No direct role in photosynthesis. Role in Cellular Respiration: Glycolysis: Glucose (a 6-carbon molecule) is split into two molecules of pyruvate during glycolysis. This process occurs in the cytoplasm. Krebs Cycle: In the presence of oxygen, pyruvate enters the mitochondria and is converted into acetyl-CoA, which then enters the Krebs Cycle to produce ATP, NADH, and FADH₂. Anaerobic Conditions: If oxygen is not available, pyruvate is converted into lactate (in animals) or ethanol (in yeast) through fermentation. 4. FAD (Flavin Adenine Dinucleotide) Function: FAD is another electron carrier similar to NAD⁺, involved in transferring electrons during cellular respiration. It exists in two forms: FAD (oxidized) and FADH₂ (reduced). Role in Photosynthesis: No direct role in photosynthesis. Role in Cellular Respiration: Krebs Cycle: FAD is reduced to FADH₂ during the Krebs Cycle. FADH₂ carries electrons to the electron transport chain. Electron Transport Chain: FADH₂ donates its electrons to the second protein complex in the ETC, resulting in the production of ATP. Each FADH₂ molecule generates slightly less ATP (around 1.5 molecules) compared to NADH (which generates about 2.5 ATP). 5. FADH₂ (Reduced Flavin Adenine Dinucleotide) Function: FADH₂ is a reduced form of FAD, carrying high-energy electrons to the electron transport chain during cellular respiration. Role in Photosynthesis: No direct role in photosynthesis. Role in Cellular Respiration: Krebs Cycle: FADH₂ is generated during the oxidation of succinate to fumarate in the Krebs Cycle. Electron Transport Chain: FADH₂ delivers electrons to the ETC, contributing to the generation of ATP. However, it enters the ETC at a later point than NADH, so it produces fewer ATP molecules (1.5 per FADH₂). Summary of Key Functions in Photosynthesis and Cellular Respiration: Molecule Photosynthesis Role Cellular Respiration Role ATP Produced in light-dependent Main energy molecule produced during reactions; powers Calvin Cycle glycolysis, Krebs Cycle, ETC NADH N/A (NADPH is used in Carries electrons from glycolysis and photosynthesis) Krebs Cycle to the ETC Pyruvate N/A (no role in photosynthesis) The end product of glycolysis; precursor for Krebs Cycle (as Acetyl-CoA)  FAD N/A Electron carrier that gets reduced to FADH₂ in Krebs Cycle FADH₂ N/A Carries electrons to the ETC to contribute to ATP production These molecules are vital for the energy transformations that take place in both photosynthesis and cellular respiration, driving the production and utilization of energy necessary for life. 1. Aerobic Respiration Aerobic respiration is the process of breaking down glucose (or other organic molecules) into energy in the presence of oxygen. It is the most efficient method of producing ATP, which is the primary energy carrier in cells. Key Features: Oxygen Required: Yes. Location: Mitochondria (in eukaryotic cells). Energy Yield: Up to 36-38 ATP molecules per glucose molecule. End Products: Carbon dioxide (CO₂), Water (H₂O), and ATP. Stages of Aerobic Respiration: 1. Glycolysis: Occurs in the cytoplasm, where glucose is broken down into two molecules of pyruvate. This produces a small amount of ATP and NADH. 2. Krebs Cycle (Citric Acid Cycle): Occurs in the mitochondrial matrix, where pyruvate is converted into acetyl-CoA and enters the cycle, generating NADH, FADH₂, and ATP. 3. Electron Transport Chain (ETC) and Oxidative Phosphorylation: Occurs in the inner mitochondrial membrane. Electrons from NADH and FADH₂ are transferred through the ETC, powering the production of ATP. Oxygen acts as the final electron acceptor, forming water. Summary of Aerobic Respiration: Overall Equation: C6H12O6+6O2→6CO2+6H2O+36−38 ATPC_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O + 36-38 \, \text{ATP}C6​H12​O6​+6O2​→6CO2​+6H2​O+36−38ATP Energy Efficiency: Aerobic respiration produces significantly more ATP compared to anaerobic processes. 2. Anaerobic Respiration Anaerobic respiration is the process of producing energy without oxygen. It is less efficient than aerobic respiration and usually occurs when oxygen is scarce or absent. Key Features: Oxygen Required: No. Location: Cytoplasm. Energy Yield: Only 2 ATP molecules per glucose molecule. End Products: Varies depending on the organism. Common end products include lactic acid (in animals) or ethanol and CO₂ (in yeast and plants). Stages of Anaerobic Respiration: 1. Glycolysis: Same as in aerobic respiration. Glucose is broken down into pyruvate, producing 2 ATP and NADH. 2. Fermentation (if oxygen is absent): Pyruvate is converted into either lactate (in animals) or ethanol and carbon dioxide (in yeast and plants), regenerating NAD⁺ to allow glycolysis to continue. Summary of Anaerobic Respiration: Energy Efficiency: Much less efficient, as only 2 ATP molecules are produced per glucose molecule. 3. Fermentation Fermentation is a type of anaerobic process that allows cells to regenerate NAD⁺ by converting pyruvate into simpler molecules. This allows glycolysis to continue in the absence of oxygen, although fermentation itself does not produce ATP directly (beyond what is produced in glycolysis). Types of Fermentation: 3.1. Lactic Acid Fermentation: Occurs In: Muscle cells of animals and some bacteria. Process: Pyruvate is reduced to lactic acid by NADH, regenerating NAD⁺ for glycolysis. End Product: Lactic acid (lactate). Example: When oxygen is low (e.g., during intense exercise), muscles undergo lactic acid fermentation, which can lead to muscle fatigue. Equation: C6H12O6→2C3H6O3+2ATPC_6H_{12}O_6 \rightarrow 2C_3H_6O_3 + 2ATPC6​H12​O6​→2C3​H6​O3​+2ATP (Glucose → Lactic acid + ATP) 3.2. Alcoholic Fermentation: Occurs In: Yeast, plants, and some bacteria. Process: Pyruvate is broken down into ethanol and carbon dioxide, regenerating NAD⁺. End Products: Ethanol and CO₂. Example: Alcoholic fermentation is used in brewing, winemaking, and bread-making. Equation: C6H12O6→2C2H5OH+2CO2+2ATPC_6H_{12}O_6 \rightarrow 2C_2H_5OH + 2CO_2 + 2ATPC6​H12​O6​→2C2​H5​OH+2CO2​+2ATP (Glucose → Ethanol + Carbon dioxide + ATP) Summary of Fermentation: Energy Yield: Only 2 ATP molecules are produced from glycolysis. Purpose: The primary role of fermentation is to regenerate NAD⁺ so that glycolysis can continue in the absence of oxygen. Comparison of Aerobic and Anaerobic Respiration: Characteristic Aerobic Respiration Anaerobic Respiration Oxygen Yes No Requirement Location Mitochondria (in eukaryotes) Cytoplasm ATP Yield 36-38 ATP per glucose 2 ATP per glucose End Products CO₂ and H₂O Lactic acid or ethanol + CO₂ Examples Occurs in most cells (e.g., Occurs in yeast, bacteria, and humans, plants) muscle cells Efficiency High (complete oxidation of Low (incomplete breakdown of glucose) glucose) Key Takeaways: Aerobic respiration is more efficient and generates more ATP but requires oxygen. Anaerobic respiration allows organisms to survive in environments with little or no oxygen, though it produces much less ATP.  Fermentation is a type of anaerobic process that allows glycolysis to continue by regenerating NAD⁺, with different end products depending on the organism (lactic acid in animals or ethanol in yeast). 1. Proteins in Plants Structure: Proteins in plants, like all organisms, are made up of amino acids linked in chains. Function: In plants, proteins play critical roles in: ○ Enzymatic activity: Enzymes like rubisco help catalyze reactions in photosynthesis (e.g., carbon fixation in the Calvin cycle). ○ Structural support: Proteins provide structural strength to the cell wall and are part of the cytoskeleton. ○ Transport: Membrane proteins help move nutrients and ions across the cell membrane. 2. Lipids in Plants Structure: Lipids are composed of fatty acids and glycerol. Function: In plants, lipids serve multiple important functions: ○ Energy storage: Lipids in seeds store energy for germination (e.g., in oil-rich seeds like sunflower). ○ Cell membranes: Phospholipids make up the cell membranes, which help protect plant cells and control the movement of substances in and out. ○ Waterproofing: Waxy coatings (cuticle) on leaves prevent water loss. 3. Carbohydrates in Plants Structure: Made of carbon, hydrogen, and oxygen, carbohydrates include simple sugars (monosaccharides) and complex forms like starch and cellulose. Function: ○ Energy storage: Plants store glucose in the form of starch, which can be broken down to release energy when needed. ○ Structural support: Cellulose is a carbohydrate that forms the primary component of the plant cell wall, giving the plant its rigid structure. ○ Photosynthesis: Glucose is produced during photosynthesis and used for growth and energy. 4. Nucleic Acids in Plants  Structure: Nucleic acids, such as DNA and RNA, are made of nucleotides. Function: ○ DNA stores the genetic information of the plant and guides growth, reproduction, and development. ○ RNA plays a role in protein synthesis by translating the genetic code into proteins required for plant functions like photosynthesis, nutrient absorption, and growth. 5. Anabolism and Catabolism in Plants Anabolism in Plants: Definition: Anabolic processes build larger molecules from smaller ones, requiring energy (usually from ATP). Example in Plants: ○ Photosynthesis is an anabolic process. It uses sunlight energy to convert carbon dioxide (CO₂) and water (H₂O) into glucose (C₆H₁₂O₆), a complex carbohydrate, and oxygen (O₂). Catabolism in Plants: Definition: Catabolic processes break down complex molecules into simpler ones, releasing energy. Example in Plants: ○ Cellular respiration is a catabolic process. It breaks down glucose into carbon dioxide and water, releasing energy in the form of ATP that the plant can use for various activities like growth and repair. 6. Chlorophyll and Chloroplasts Chlorophyll: Definition: Chlorophyll is a green pigment found in plant cells. Function: It absorbs sunlight, primarily in the blue and red wavelengths, and converts light energy into chemical energy during photosynthesis. Location: Chlorophyll is located in the thylakoid membranes inside the chloroplasts. Chloroplasts: Definition: Chloroplasts are organelles in plant cells responsible for photosynthesis. Function: ○ Photosynthesis occurs here: Chloroplasts capture light energy and convert it into chemical energy (glucose) during the process of photosynthesis.  ○ Structure: Thylakoids: Disc-like structures where the light-dependent reactions of photosynthesis take place. Stroma: The fluid-filled space where the Calvin Cycle (light-independent reactions) occurs, producing glucose from carbon dioxide. Summary of Biomolecules and Cellular Structures in Plants: Proteins: Enzymes like rubisco are crucial in photosynthesis, transport, and structure. Lipids: Store energy in seeds, form cell membranes, and protect plants with waterproof coatings. Carbohydrates: Glucose is produced in photosynthesis, starch stores energy, and cellulose forms cell walls. Nucleic Acids: DNA and RNA are responsible for storing genetic information and producing proteins. Anabolism: Photosynthesis builds glucose from CO₂ and water. Catabolism: Cellular respiration breaks down glucose to release energy. Chlorophyll: A green pigment that absorbs light for photosynthesis. Chloroplasts: Organelles where photosynthesis takes place.