Photosynthesis and Cellular Respiration Quiz
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Questions and Answers

What is the primary role of photosystems I and II in photosynthesis?

  • Transport electrons to the terminal electron acceptor
  • Synthesize ATP directly from ADP
  • Capture inorganic phosphate
  • Absorb free energy from light and boost electrons (correct)

What establishes the electrochemical gradient across the thylakoid membrane during the light-dependent reactions?

  • Absorption of carbon dioxide
  • Transfer of ATP to ADP
  • Transfer of electrons through the electron transport chain (correct)
  • Movement of protons through ATP synthase

Which molecule serves as the terminal electron acceptor in photosynthesis?

  • NADP+ (correct)
  • NADH
  • Oxygen
  • FADH2

During the Calvin cycle, what is primarily synthesized from carbon dioxide?

<p>Organic molecules (B)</p> Signup and view all the answers

In cellular respiration, which electron carriers deliver electrons to the electron transport chain?

<p>NADH and FADH2 (A)</p> Signup and view all the answers

What compound is produced in the light-dependent reactions of photosynthesis?

<p>ATP and NADPH (C)</p> Signup and view all the answers

Which part of the chloroplast is involved in the Calvin cycle?

<p>Stroma (A)</p> Signup and view all the answers

What is the function of ATP synthase in photosynthesis?

<p>Synthesize ATP from ADP and inorganic phosphate (A)</p> Signup and view all the answers

Which of the following structures is responsible for the absorption of light energy in plants?

<p>Chloroplasts (C)</p> Signup and view all the answers

What is the primary role of stomata in plant leaves?

<p>To facilitate gas exchange (C)</p> Signup and view all the answers

Which process describes the conversion of carbon dioxide and water into glucose and oxygen using light energy?

<p>Photosynthesis (A)</p> Signup and view all the answers

During the oxidation process in cellular respiration, what is produced from glucose and oxygen?

<p>Carbon dioxide and water (D)</p> Signup and view all the answers

What is the purpose of chlorophyll in the process of photosynthesis?

<p>To absorb sunlight for converting carbon dioxide and water into glucose (B)</p> Signup and view all the answers

Which of the following nutrients is NOT typically absorbed through the roots of plants?

<p>Oxygen (A)</p> Signup and view all the answers

What is the end product of photosynthesis?

<p>Glucose and oxygen (D)</p> Signup and view all the answers

The endosymbiotic theory explains the evolution of which cellular structure involved in photosynthesis?

<p>Chloroplasts (A)</p> Signup and view all the answers

What is the net product of one complete cycle of carbon fixation?

<p>One G3P molecule (B)</p> Signup and view all the answers

How many ATP molecules are consumed during three turns of the carbon fixation cycle?

<p>9 ATP molecules (B)</p> Signup and view all the answers

Which enzyme catalyzes the initial reaction in the carbon fixation process?

<p>RuBisCo (C)</p> Signup and view all the answers

What are the products formed after the reduction phase of the carbon fixation cycle?

<p>Glyceraldehyde-3-P (G3P) (C)</p> Signup and view all the answers

What is regenerated at the end of the carbon fixation cycle to continue the process?

<p>RuBP and ATP (C)</p> Signup and view all the answers

Which of the following best describes the role of light energy in the process of electron flow?

<p>It drives the synthesis of ATP and NADPH. (A)</p> Signup and view all the answers

What happens to P680 after it absorbs a photon of light?

<p>It loses an electron to the primary electron acceptor. (A)</p> Signup and view all the answers

What is produced when water is split during photosynthesis?

<p>Electrons, protons, and an oxygen atom are produced. (A)</p> Signup and view all the answers

Why is P680+ considered the strongest oxidizing agent known?

<p>It can readily oxidize other molecules by removing electrons. (D)</p> Signup and view all the answers

What is the result of the transfer of electrons from the primary electron acceptor in Photosystem II?

<p>It initiates a new flow of electrons from Photosystem I. (A)</p> Signup and view all the answers

Which of the following statements about electron transfer in photosynthesis is false?

<p>Light absorption by pigments occurs after the electrons are transferred. (D)</p> Signup and view all the answers

How does the flow of electrons contribute to the overall process of photosynthesis?

<p>It generates proton gradients used for ATP synthesis. (D)</p> Signup and view all the answers

In the linear electron flow, what happens after P680 transfers its electron?

<p>P680 must replace the lost electron by splitting water. (A)</p> Signup and view all the answers

Which option is NOT a function of Photosystem II?

<p>Release of carbon dioxide (D)</p> Signup and view all the answers

What is primarily produced during cyclic photophosphorylation?

<p>ATP only (B)</p> Signup and view all the answers

What adaptation allows CAM plants to conserve water during daytime?

<p>They absorb CO2 during the night (B)</p> Signup and view all the answers

What is the effect of photorespiration on the Calvin cycle?

<p>It leads to a loss of carbon to production of CO2. (D)</p> Signup and view all the answers

Which observation best supports the idea that Elysia chlorotica can perform photosynthesis?

<p>It grows in the absence of food sources when exposed to light. (A)</p> Signup and view all the answers

Which molecule is NOT produced in the light reactions of photosynthesis?

<p>G3P (C)</p> Signup and view all the answers

Which process allows C4 plants to minimize photorespiration?

<p>By using different cells for carbon fixation and the Calvin cycle. (D)</p> Signup and view all the answers

What role does NADP+ play in photosynthesis?

<p>It accepts electrons in the light-dependent reactions. (A)</p> Signup and view all the answers

Which enzyme is primarily involved in the carbon fixation process of C4 plants?

<p>PEP carboxylase (C)</p> Signup and view all the answers

Which substance is synthesized in the Calvin cycle from carbon dioxide?

<p>G3P (C)</p> Signup and view all the answers

How do CAM plants optimize their carbon fixation?

<p>By partitioning photosynthesis between day and night. (D)</p> Signup and view all the answers

What is a significant impact of the increase of O2 levels in the atmosphere on Rubisco?

<p>Rubisco has become less efficient, accepting both CO2 and O2. (D)</p> Signup and view all the answers

What is the primary output of the light-dependent reactions?

<p>ATP and NADPH (A)</p> Signup and view all the answers

What is the main reason for plants to evolve alternative carbon fixation systems?

<p>To enhance the efficiency of carbon fixation. (B)</p> Signup and view all the answers

During hot, dry days, how do C3 plants respond to conserve water?

<p>By partially closing stomata to reduce CO2 intake. (D)</p> Signup and view all the answers

What can potentially improve a plant's efficiency in carbon fixation if photorespiration is reduced?

<p>50% more effectiveness in photosynthesis. (C)</p> Signup and view all the answers

What is the net product of three turns of the carbon fixation cycle?

<p>One G3P molecule (D)</p> Signup and view all the answers

How many ATP and NADPH molecules are consumed in the synthesis of sugar from carbon fixation?

<p>9 ATP and 6 NADPH (B)</p> Signup and view all the answers

Which molecule is directly involved in the regeneration of RuBP during the Calvin cycle?

<p>G3P (B)</p> Signup and view all the answers

What is the role of RuBisCo in the processes described?

<p>To catalyze the conversion of RuBP to 3-PGA (A)</p> Signup and view all the answers

What happens to ATP and NADPH after being utilized in the Calvin cycle?

<p>They are regenerated for future reactions (C)</p> Signup and view all the answers

What drives ATP synthesis during the light-dependent reactions?

<p>The fall of electrons through the electron transport chain (C), Diffusion of protons from the thylakoid space into the stroma (D)</p> Signup and view all the answers

What is the primary change occurring to P700 in Photosystem I after it receives energy from light?

<p>P700 loses an electron to an electron acceptor (D)</p> Signup and view all the answers

Which statement best describes the role of P680 in Photosystem II?

<p>P680 absorbs photons and initiates the process of electron transfer (D)</p> Signup and view all the answers

How does the electron transport chain affect proton movement across the thylakoid membrane?

<p>It creates a proton gradient by moving protons into the thylakoid space (A)</p> Signup and view all the answers

What happens to P700 after it has accepted an electron from the electron transport chain?

<p>P700 is reduced and can participate in light absorption again (B)</p> Signup and view all the answers

What is the primary reason for the existence of cyclic electron flow in photosynthesis?

<p>To generate surplus ATP when ATP supplies are low (D)</p> Signup and view all the answers

Which statement accurately describes the function of photosystem I in the light reactions?

<p>Photosystem I produces NADPH and generates ATP through cyclic flow. (D)</p> Signup and view all the answers

In what condition does the cyclic electron flow become more prevalent in photosynthetic cells?

<p>When the ATP demand exceeds the available NADPH (C)</p> Signup and view all the answers

Which of the following best describes the role of water in photosynthesis?

<p>Source of protons and electrons to facilitate ATP production (A)</p> Signup and view all the answers

What is the significance of the photoprotective role of cyclic electron flow?

<p>It mitigates damage to photosystem proteins caused by excess light (C)</p> Signup and view all the answers

Which pigment molecules play a crucial role in capturing light energy for photosystems?

<p>Chlorophyll a and b along with carotenoids (B)</p> Signup and view all the answers

What is the end product of the light reactions that serves as reducing power for the Calvin cycle?

<p>NADPH (B)</p> Signup and view all the answers

What is the source of electrons for chloroplasts during the process of photosynthesis?

<p>Water (A)</p> Signup and view all the answers

How does ATP synthesis differ between chloroplasts and mitochondria?

<p>Protons are pumped into the thylakoid space in chloroplasts and into the intermembrane space in mitochondria (D)</p> Signup and view all the answers

Where does the oxygen produced during photosynthesis primarily originate?

<p>From the splitting of water (A)</p> Signup and view all the answers

What type of phosphorylation occurs in chloroplasts to produce ATP?

<p>Photophosphorylation (B)</p> Signup and view all the answers

Which component is pumped into the thylakoid space during the light-dependent reactions?

<p>Protons (B)</p> Signup and view all the answers

In which part of the chloroplast does ATP synthesis occur during photosynthesis?

<p>Thylakoid membrane (D)</p> Signup and view all the answers

What is a significant similarity between chemiosmosis in chloroplasts and mitochondria?

<p>Both utilize ATP synthase (D)</p> Signup and view all the answers

What role does the proton gradient play in ATP production in chloroplasts?

<p>It fuels the diffusion back into the stroma via ATP synthase (A)</p> Signup and view all the answers

What role do chlorophylls play during the light-dependent reactions of photosynthesis?

<p>They absorb light energy to energize electrons. (B)</p> Signup and view all the answers

Which process establishes a proton gradient across the thylakoid membrane?

<p>The transfer of electrons through the electron transport chain. (D)</p> Signup and view all the answers

During photosynthesis, why is NADP+ important?

<p>It serves as the terminal electron acceptor. (A)</p> Signup and view all the answers

What is the primary energy-capturing process used by photosynthetic organisms?

<p>Capture of free energy from sunlight. (C)</p> Signup and view all the answers

What connects Photosystems I and II in the process of photosynthesis?

<p>The transfer of free energy electrons through an electron transport chain. (D)</p> Signup and view all the answers

In which part of the chloroplast does the Calvin cycle occur?

<p>Stroma. (D)</p> Signup and view all the answers

How does ATP synthase function in the light-dependent reactions?

<p>It synthesizes ATP from ADP and inorganic phosphate using a proton gradient. (B)</p> Signup and view all the answers

What happens to the electrons during the electron transport chain in chloroplasts?

<p>They are passed to a series of electron acceptors, ultimately leading to ATP synthesis. (D)</p> Signup and view all the answers

What is the primary function of chloroplasts in plant cells?

<p>Photosynthesis (C)</p> Signup and view all the answers

In which part of the chloroplast is chlorophyll located?

<p>Thylakoid membrane (C)</p> Signup and view all the answers

How many chloroplasts are typically found per square millimeter of leaf tissue?

<p>500,000 (D)</p> Signup and view all the answers

What is the primary role of thylakoids within chloroplasts?

<p>Absorption of light energy (C)</p> Signup and view all the answers

What is found in the stroma of a chloroplast?

<p>Dense fluid with enzymes (C)</p> Signup and view all the answers

Which structure in the chloroplast facilitates the building of a proton gradient?

<p>Thylakoid membrane (C)</p> Signup and view all the answers

Which of the following is NOT a component of a chloroplast?

<p>Mitochondrial matrix (D)</p> Signup and view all the answers

What process occurs primarily in the chloroplasts' thylakoid membranes?

<p>Light-dependent reactions (A)</p> Signup and view all the answers

Flashcards

Autotrophs capture energy

Autotrophs obtain energy from non-living sources in the environment.

Photosynthesis light reactions

A series of reactions using light energy to produce ATP and NADPH, powering sugar creation.

Photosystems I & II

Structures in chloroplasts that absorb light, boosting electrons to higher energy levels during photosynthesis.

Electron Transport Chain (ETC)

A sequence of reactions where electrons transfer, building a hydrogen ion gradient.

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Proton gradient

A difference in proton concentration across a membrane, used for ATP production.

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ATP synthase

An enzyme that produces ATP from ADP and phosphate using the proton gradient's energy.

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Calvin cycle

The process in photosynthesis that produces sugars from carbon dioxide using ATP and NADPH.

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Electron acceptor

A molecule that receives electrons, which is crucial in both photosynthesis and cellular respiration.

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Photoautotrophs

Organisms that use light energy to synthesize organic molecules from inorganic sources.

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Autotrophs

Organisms that produce their own food through processes like photosynthesis.

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Photosynthesis

The process by which autotrophs convert light energy into chemical energy in the form of organic molecules.

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Chloroplasts

Organelles within plant cells where photosynthesis takes place.

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Stomata

Tiny pores on the leaves that allow gas exchange, particularly for CO2 intake and O2 release.

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Chlorophyll

The green pigment in chloroplasts that absorbs light energy for photosynthesis.

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Endergonic reaction

A reaction that requires energy input to proceed.

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Exergonic reaction

A reaction that releases energy.

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Light-driven ATP and NADPH synthesis

Light energy powers the creation of ATP and NADPH through energized photosystems and electron flow.

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Photosystem II (PS II)

A photosystem that captures light energy and initiates electron flow in photosynthesis.

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P680

A chlorophyll molecule in PS II that absorbs light, excites electrons, and starts electron transport.

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Primary electron acceptor

Molecule that accepts energized electrons from chlorophyll in Photosystems.

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Linear electron flow

The process of electron movement from Photosystem II to Photosystem I in photosynthesis, creating ATP and NADPH.

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Water splitting

Process in photosynthesis where water molecules are broken down to provide electrons, protons, and oxygen.

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Oxidizing agent

A substance that gains electrons in a chemical reaction; in this case, P680+

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Oxygen release

Oxygen is released as a byproduct of water splitting in photosynthesis.

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Carbon Fixation

The initial step of the Calvin Cycle where CO2 is incorporated into an organic molecule

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Calvin Cycle - Reduction

The step in the Calvin cycle where Glyceraldehyde-3-phosphate (G3P) is produced using ATP & NADPH, turning PGA into G3P.

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Calvin Cycle - Regeneration

The step in the Calvin cycle where RuBP (ribulose bisphosphate) is recreated from G3P to continue the cycle

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Calvin Cycle Product (Net)

The Calvin Cycle produces one G3P molecule per three turns.

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Calvin Cycle Energy Cost

To produce one G3P molecule, the Calvin cycle requires 9 ATP and 6 NADPH.

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Photorespiration

A process where Rubisco mistakenly binds to oxygen instead of carbon dioxide, leading to the release of carbon dioxide and a decrease in photosynthetic efficiency.

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Rubisco's Dilemma

Rubisco evolved in an atmosphere rich in carbon dioxide, so it doesn't discriminate well between carbon dioxide and oxygen. This leads to photorespiration, reducing photosynthetic efficiency in today's oxygen-rich atmosphere.

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C3 Plants

Plants that fix carbon directly using the Calvin cycle in mesophyll cells, making a 3-carbon compound.

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CAM Plants

Plants that open their stomata at night to take in carbon dioxide, storing it as an acid, then releasing it during the day for the Calvin cycle.

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PEP Carboxylase

An enzyme used in C4 plants to fix carbon dioxide effectively into a 4-carbon compound, even under low carbon dioxide conditions.

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Bundle Sheath Cells

Specialized cells in C4 plants where the Calvin cycle takes place, surrounded by mesophyll cells where carbon dioxide is initially fixed.

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Photosystem II

A complex of proteins and pigments within chloroplasts that captures light energy and uses it to split water molecules, releasing oxygen and generating high-energy electrons.

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Electron Transport Chain (Photosynthesis)

A series of molecules within chloroplasts that pass electrons from one to another, releasing energy to pump protons across a membrane, ultimately forming a proton gradient.

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Photosystem I

A complex of proteins and pigments in chloroplasts that absorbs light energy, boosting electrons to a higher energy level, ultimately contributing to the formation of NADPH.

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ATP

Adenosine triphosphate, a molecule that stores and releases energy within cells, essential for various metabolic processes, including photosynthesis and cellular respiration.

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NADPH

Nicotinamide adenine dinucleotide phosphate, a molecule that carries electrons and hydrogen ions within cells, acting as a reducing agent in various metabolic reactions.

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Cyclic Photophosphorylation

A process in photosynthesis where electrons cycle back through Photosystem I, generating ATP but not NADPH, a mechanism to produce extra ATP needed for carbon fixation.

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Thylakoid Membranes

Membranes within chloroplasts that are arranged in stacks called grana, containing chlorophyll and other molecules for capturing light energy.

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Grana

Stacks of thylakoid membranes within chloroplasts where light-dependent reactions of photosynthesis occur.

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Light-Dependent Reactions

The first stage of photosynthesis where light energy is captured and converted into chemical energy (ATP & NADPH).

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Oxygen

The terminal electron acceptor in cellular respiration, receiving electrons from the Electron Transport Chain and combining with protons to form water.

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Electrochemical Gradient

A difference in both electrical charge and concentration of ions across a membrane, generated by the movement of electrons in the Electron Transport Chain.

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Terminal Electron Acceptor

The final electron acceptor, like oxygen in cellular respiration or NADP+ in photosynthesis, that receives electrons at the end of the electron transport chain.

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Calvin Cycle: Carbon Fixation

The first step of the Calvin cycle where carbon dioxide (CO2) is incorporated into an organic molecule, RuBP (ribulose bisphosphate), catalyzed by the enzyme Rubisco.

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G3P - What is it?

Glyceraldehyde-3-phosphate (G3P) is a 3-carbon sugar that is the product of the Calvin cycle. It is the building block for glucose and other organic molecules.

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Net G3P Output

After three turns of the Calvin cycle, one net G3P molecule is produced, which can be used to synthesize glucose or other organic molecules.

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How does light energy get converted to chemical energy?

In photosynthesis, light energy excites electrons in chlorophyll, initiating electron transport. This energy flow pumps protons across the thylakoid membrane, creating a proton gradient used to generate ATP. Simultaneously, electrons are used to reduce NADP+ to NADPH. Both ATP and NADPH are then utilized in the Calvin cycle to convert carbon dioxide into sugar.

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What is the role of the proton gradient in photosynthesis?

The proton gradient, created by the movement of protons across the thylakoid membrane during electron transport, stores potential energy. This energy is then released as protons flow back across the membrane through ATP synthase, driving the synthesis of ATP.

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What's the difference between Photosystem II and Photosystem I?

Photosystem II captures light energy and uses it to split water, releasing oxygen and generating high-energy electrons. Photosystem I uses light energy to boost electrons to an even higher energy level, generating NADPH. Both systems work together in the light-dependent reactions of photosynthesis.

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What is the purpose of the Calvin Cycle?

The Calvin Cycle is a series of reactions that uses the energy from ATP and NADPH (produced in the light reactions) to convert carbon dioxide into glucose, the primary energy source for plants.

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What is the key enzyme in carbon fixation?

Rubisco is a critical enzyme responsible for fixing carbon dioxide into an organic molecule, initiating the Calvin Cycle. It is a complex enzyme with a unique ability to bind both carbon dioxide and oxygen, leading to both photosynthesis and photorespiration.

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O2 Source in Photosynthesis

The oxygen (O2) produced during photosynthesis comes from the splitting of water molecules (H2O), not from carbon dioxide (CO2).

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Energy Source in Photosynthesis

Light energy is the primary energy source for photosynthesis, powering the conversion of light energy into chemical energy stored in ATP and NADPH.

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Electron Source in Photosynthesis

Water molecules (H2O) provide the electrons that are energized during the light-dependent reactions of photosynthesis.

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Chemiosmosis in Chloroplasts

In chloroplasts, protons (H+) are pumped into the thylakoid space, creating a proton gradient that drives ATP synthesis as they diffuse back into the stroma through ATP synthase.

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Chemiosmosis in Mitochondria vs. Chloroplasts

Both mitochondria and chloroplasts use chemiosmosis to generate ATP, but they differ in the source of energy and the location of the proton gradient. Mitochondria use food for energy and pump protons to the intermembrane space, while chloroplasts use light energy and pump protons into the thylakoid space.

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Chloroplasts vs. Mitochondria: ATP Production

Chloroplasts use light energy to convert water into ATP while mitochondria use food energy (glucose) to generate ATP through oxidative phosphorylation.

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Role of Photosystems I and II

Photosystem II (PSII) captures light energy and uses it to split water, releasing oxygen and providing electrons for the electron transport chain. Photosystem I (PSI) absorbs light energy that boosts electrons to a higher energy level, leading to the formation of NADPH.

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ATP and NADPH in Calvin Cycle

ATP and NADPH, products of the light-dependent reactions, are used as energy sources and reducing power, respectively, in the Calvin cycle to fix carbon dioxide and generate sugar (G3P).

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What is the ultimate source of electrons?

Light is the ultimate source of electrons in photosynthesis. Light energy excites electrons within chlorophyll molecules, initiating the electron flow.

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PS II generates...

Photosystem II (PS II) generates energy in the form of ATP through the process of photophosphorylation. PS II uses light energy to create a proton gradient across a membrane, which is then used by ATP synthase to produce ATP.

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PS I generates...

Photosystem I (PS I) generates reducing power as NADPH. PS I uses light energy to boost electrons to a higher energy level, which are then passed on to NADP+ to generate NADPH.

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Cyclic electron flow

Cyclic electron flow is a process that uses only PS I and produces ATP, but not NADPH. Electrons cycle through PS I back to the beginning instead of moving on to PS II.

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Why does cyclic electron flow exist?

Cyclic electron flow exists because sometimes cells need more ATP than NADPH. It helps to balance the ATP/NADPH ratio when there's a surplus of NADPH, or when there's particularly high demand for ATP.

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Photoprotective role

Cyclic electron flow can play a photoprotective role. It can help prevent damage to photosynthetic proteins by excess light energy and promote repair of any light-induced damage.

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Study Notes

Photosynthesis Overview

  • Photosynthesis is the process that converts solar energy into chemical energy.
  • Autotrophs, like plants, use sunlight to create organic molecules.
  • Heterotrophs consume organic molecules created from other organisms.

Chloroplasts

  • Chloroplasts are organelles mainly found in mesophyll cells of leaves.
  • They contain chlorophyll, a green pigment important for light absorption.
  • Chloroplasts have a double outer membrane and internal thylakoid membranes that are stacked into grana.
  • The stroma is the fluid-filled interior surrounding the thylakoid membranes.

Photosynthesis Stages

  • Photosynthesis has two main stages: the light reactions and the Calvin cycle.
  • Light Reactions occur in the thylakoid membranes and convert light energy into chemical energy in the form of ATP and NADPH.
  • The Calvin cycle, occurring in the stroma, uses ATP and NADPH to convert CO2 into sugar (G3P).

Light Reactions

  • Light excites electrons in chlorophyll, triggering a series of electron transport chain reactions.
  • Water is split (photolysis) in this process, releasing oxygen as a byproduct.
  • The electron transport chain generates a proton gradient across the thylakoid membrane.
  • This gradient drives ATP synthesis through chemiosmosis.
  • Electrons are passed to NADP+ to form NADPH.

Calvin Cycle

  • Carbon dioxide (CO2) is incorporated into an existing 5-carbon molecule (RuBP) via the enzyme RuBisCo.
  • This creates a 6-carbon molecule, which immediately splits into two 3-carbon molecules (3-PGA).
  • ATP and NADPH are used to convert 3-PGA into glyceraldehyde-3-phosphate (G3P).
  • G3P is a sugar precursor for glucose production or other organic compounds.
  • RuBP is regenerated in the cycle to keep the process going.

Alternative Carbon Fixation Pathways

  • C3 photosynthesis is the most common pathway.
  • C4 plants have a spatial separation of carbon fixation and the Calvin cycle to reduce photorespiration.
  • CAM plants temporally separate carbon fixation and the Calvin cycle to conserve water in arid environments.

Photorespiration

  • Photorespiration is a process that occurs when rubisco uses oxygen in the Calvin cycle rather than carbon dioxide.
  • This process wastes energy and reduces photosynthetic efficiency.
  • C4 and CAM plants minimize photorespiration compared to C3 plants, primarily by fixing carbon dioxide in different compartments before the Calvin cycle.

Summary

  • Photosynthesis efficiently converts light energy into chemical energy, making sugar and other organic molecules.
  • Light reactions establish an energy source via ATP and reducing power via NADPH.
  • These are used in the Calvin cycle to synthesize glucose and other essential compounds.
  • Adaptations to minimize photorespiration, such as those seen in C4 and CAM plants, are significant adaptations for plants thriving in diverse environments.

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Description

Test your knowledge on the essential processes of photosynthesis and cellular respiration. This quiz covers key concepts, including the roles of photosystems I and II, the Calvin cycle, and electron transport chains. Perfect for students wanting to reinforce their understanding of plant biology and energy production.

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