Photosynthesis Overview
42 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the primary function of ATP in biological systems?

  • To provide structural support to cells
  • To store energy for future use
  • To serve as a genetic material
  • To drive cellular processes (correct)

What type of reaction occurs during the hydrolysis of ATP?

  • Endergonic reaction
  • Anabolic reaction
  • Exergonic reaction (correct)
  • Catabolic reaction

What does the process of anabolism involve?

  • Breaking down large molecules
  • Converting light energy into chemical energy
  • Releasing energy
  • Synthesizing large molecules from smaller units (correct)

Which of the following describes catabolism?

<p>It breaks down large molecules into smaller units. (D)</p> Signup and view all the answers

What is the result of the condensation reaction involving ADP and inorganic phosphate?

<p>Synthesis of ATP (D)</p> Signup and view all the answers

Which type of energy is harvested from the sun?

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

What happens to the energy during the synthesis of ATP from ADP and inorganic phosphate?

<p>Energy is absorbed. (A)</p> Signup and view all the answers

What constitutes the structure of ATP?

<p>One adenosine and three phosphate groups (A)</p> Signup and view all the answers

What is the primary distinction between oxidation and reduction reactions?

<p>Oxidation involves loss of electrons, while reduction involves gain of electrons. (B)</p> Signup and view all the answers

Which of the following statements accurately describes NADH and NAD+?

<p>NAD+ is reduced to NADH during cellular respiration. (C)</p> Signup and view all the answers

What occurs to the reducing agent during a redox reaction?

<p>It loses electrons and becomes oxidized. (B)</p> Signup and view all the answers

Which component of the chloroplast is involved in the photosynthetic light-dependent reactions?

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

In a redox reaction, what role does the oxidizing agent play?

<p>It causes another substrate to lose electrons. (D)</p> Signup and view all the answers

In photosynthesis, what is the primary role of the oxidizing agent?

<p>To gain electrons and become reduced, thus aiding in energy conversion. (B)</p> Signup and view all the answers

Which statement about aerobic and anaerobic respiration is correct?

<p>Anaerobic respiration does not involve oxygen in the metabolic pathway. (D)</p> Signup and view all the answers

Which type of organism uses light as an energy source and organic compounds as a carbon source?

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

What characteristic is true of phototrophic energy metabolism?

<p>It primarily obtains energy from sunlight. (D)</p> Signup and view all the answers

Which of the following best describes the relationship between oxidation and reduction?

<p>Oxidation cannot occur without reduction, and vice versa. (D)</p> Signup and view all the answers

Where do carbon dioxide and oxygen exchange occur in leaves?

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

Which stage of photosynthesis is also known as the Calvin-Benson cycle?

<p>Light-independent reactions (B)</p> Signup and view all the answers

During the process of oxidation, what happens to the oxidized substrate?

<p>It loses electrons. (C)</p> Signup and view all the answers

What is the primary function of chlorophyll in photosynthesis?

<p>To absorb light energy (B)</p> Signup and view all the answers

What type of metabolic process is characterized by reactions that yield energy through oxidation-reduction?

<p>Chemotrophic energy metabolism. (A)</p> Signup and view all the answers

What role does the stroma play in chloroplasts?

<p>Dense fluid where light-independent reactions occur (C)</p> Signup and view all the answers

What is the main purpose of the light-dependent reactions in photosynthesis?

<p>To convert light energy into chemical energy (A)</p> Signup and view all the answers

Where do the light-dependent reactions take place within the cell?

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

Which product of the light-dependent reactions is essential for the Calvin Cycle?

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

What process occurs during the Calvin Cycle?

<p>Fixation of carbon into carbohydrates (A)</p> Signup and view all the answers

Which of the following statements about the light-dependent reactions is false?

<p>They take place in the stroma of chloroplasts. (B)</p> Signup and view all the answers

What is the primary role of chlorophyll in photosystems?

<p>To absorb photons and transfer energy to electrons (A)</p> Signup and view all the answers

Which of the following correctly identifies the components of Photosystem I?

<p>P700 and ferredoxin (A)</p> Signup and view all the answers

What occurs during fluorescence in chlorophyll molecules?

<p>Ground state electrons release energy as photons (B)</p> Signup and view all the answers

Which phase of the Calvin Cycle does carbon fixation occur?

<p>Carbon fixation phase (D)</p> Signup and view all the answers

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

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

What is the immediate product of carbon fixation in the Calvin Cycle?

<p>3-Phosphoglycerate (C)</p> Signup and view all the answers

What happens to the plant's access to carbon dioxide when stomata are closed?

<p>It decreases (D)</p> Signup and view all the answers

Which of the following is a product of the reduction phase of the Calvin Cycle?

<p>Glyceraldehyde 3-phosphate (B)</p> Signup and view all the answers

What is the fate of some of the G3P produced in the Calvin Cycle?

<p>Synthesis of starch and sucrose (D)</p> Signup and view all the answers

Which enzyme is responsible for initiating the process of carbon fixation?

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

What is a consequence of photorespiration in plants?

<p>Increased oxygen consumption (C)</p> Signup and view all the answers

Which of the following statements about the Calvin Cycle is true?

<p>It synthesizes sugar from carbon dioxide (D)</p> Signup and view all the answers

What happens to the levels of oxygen gas during the closure of stomata in plants?

<p>They increase due to limited CO2 uptake (B)</p> Signup and view all the answers

Flashcards

Energy

The ability to promote change or do work.

Chemical Energy

Energy stored in the bonds between atoms and molecules.

Solar Energy

Energy harvested from the sun.

Metabolism

The sum of all chemical reactions within a cell or organism.

Signup and view all the flashcards

Catabolism

Breaking down large molecules into smaller units.

Signup and view all the flashcards

Anabolism

Building large molecules from smaller units.

Signup and view all the flashcards

ATP

Primary energy currency in biological systems.

Signup and view all the flashcards

Hydrolysis of ATP

Breaking the phosphate bond in ATP, releasing energy.

Signup and view all the flashcards

Cellular Respiration

The process by which cells break down organic molecules (like glucose) to release energy in the form of ATP (adenosine triphosphate)

Signup and view all the flashcards

Aerobic Respiration

A type of cellular respiration that requires oxygen to produce ATP.

Signup and view all the flashcards

Anaerobic Respiration

A type of cellular respiration that doesn't need oxygen to produce ATP.

Signup and view all the flashcards

Oxidation

Loss of electrons, gain of oxygen, or loss of hydrogen

Signup and view all the flashcards

Reduction

Gain of electrons, gain of hydrogen, or loss of oxygen

Signup and view all the flashcards

Oxidizing Agent

A substance that causes another substance to lose electrons (get oxidized). It itself gets reduced.

Signup and view all the flashcards

Reducing Agent

A substance that causes another substance to gain electrons (get reduced). It itself gets oxidized.

Signup and view all the flashcards

ATP-ADP Cycle

The continuous process of ATP being broken down to ADP to release energy, and then ADP being re-formed into ATP using energy.

Signup and view all the flashcards

Photosynthesis

The process by which organisms convert light energy into chemical energy and use it to synthesize organic molecules.

Signup and view all the flashcards

Photoautotroph

Organisms that use light as an energy source and inorganic compounds (like carbon dioxide) for carbon.

Signup and view all the flashcards

Chloroplast

The organelle in plant cells where photosynthesis takes place.

Signup and view all the flashcards

Chlorophyll

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

Signup and view all the flashcards

Stroma

The dense fluid within the chloroplast, surrounding the thylakoid membranes.

Signup and view all the flashcards

Thylakoid

Membranous sacs within the chloroplast, where light-dependent reactions occur.

Signup and view all the flashcards

Light-dependent Reactions

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

Signup and view all the flashcards

Calvin Cycle

The second stage of photosynthesis, where carbon dioxide is fixed and reduced to carbohydrates, using ATP and NADPH from light-dependent reactions.

Signup and view all the flashcards

ATP and NADPH

Energy-carrying molecules produced during light-dependent reactions, used in the Calvin Cycle.

Signup and view all the flashcards

Photosystem II

A protein complex within chloroplasts that absorbs light energy and uses it to excite electrons, ultimately leading to the production of ATP.

Signup and view all the flashcards

Photosystem I

A protein complex within chloroplasts that absorbs light energy and uses it to produce NADPH, a crucial electron carrier in photosynthesis.

Signup and view all the flashcards

P680

A special pair of chlorophyll a molecules within Photosystem II that absorb light energy at a wavelength of approximately 680nm.

Signup and view all the flashcards

P700

A special pair of chlorophyll a molecules within Photosystem I that absorb light energy at a wavelength of approximately 700nm.

Signup and view all the flashcards

Photorespiration

A process that occurs in plants when they close their stomata to conserve water, leading to a buildup of oxygen and a decrease in carbon dioxide, which favors an inefficient process where carbon is lost as COâ‚‚.

Signup and view all the flashcards

Dehydration in plants

The condition where plants lose more water than they take in, often due to hot, dry conditions.

Signup and view all the flashcards

Why do plants close stomata?

Plants close their stomata to conserve water, especially in hot, dry environments. This helps prevent excessive water loss through transpiration.

Signup and view all the flashcards

What happens when stomata close?

When stomata close, the plant's access to carbon dioxide is reduced, and oxygen gas builds up inside. This creates conditions that favor photorespiration.

Signup and view all the flashcards

RuBP Regeneration

The process where Ribulose bisphosphate (RuBP), a key molecule in photosynthesis, is regenerated. This allows the Calvin cycle to continue and produce glucose.

Signup and view all the flashcards

What is the role of RuBP in photosynthesis?

Ribulose bisphosphate (RuBP) is a molecule that captures carbon dioxide in the first step of the Calvin cycle. It is essential for the process of carbon fixation.

Signup and view all the flashcards

Study Notes

Photosynthesis

  • Photosynthesis is the conversion of light energy to chemical energy, used in synthesizing organic molecules.
  • Organisms involved: Photoheterotrophs and photoautotrophs.
  • Location of photosynthesis: Primarily in the mesophyll cells of leaves.
  • Plants use the process of photosynthesis to create sugars, which are subsequently used for energy and growth.

Chloroplasts

  • Site of photosynthesis in plants
  • Parts:
    • Outer membrane
    • Inner membrane
    • Stroma (dense fluid)
    • Thylakoids
    • Grana (stacks of thylakoids)
    • Chlorophyll

Two Stages of Photosynthesis

  • Light-dependent reactions:
    • Occur in thylakoids
    • Convert light energy into chemical energy (ATP and NADPH)
    • Produce hydrogen ions (H+)
  • Calvin cycle (light-independent reactions):
    • Occurs in the stroma
    • Carbon fixation, reduction, and regeneration of ribulose bisphosphate (RuBP)
    • Requires ATP and NADPH from light-dependent reactions.

Chlorophyll

  • Green pigment
  • Absorbs light from the visible spectrum, primarily red and violet-blue light, using the energy from the photons for photosynthesis.
  • Reflects and transmits yellow and green light, giving leaves their green color.
  • Located within the thylakoid membranes of chloroplasts
  • Chlorophyll a is the main photosynthetic pigment
  • Chlorophyll b is an accessory pigment

Light-Dependent Reactions

  • Occur in thylakoids
  • Convert light energy to chemical energy (ATP and NADPH)
  • Produce hydrogen ions (H+)
  • Use photosystems (PSII and PSI)
  • Photosystem II (PSII): Water splitting, producing oxygen (O2).
  • Photosystem I (PSI): Generating NADPH from absorbed energy.
  • Electron transport chain (ETC) involved between these photosystems.

Calvin Cycle

  • Occurs in the stroma
  • Carbon fixation (using CO2)
  • Reduction of fixed carbon to carbohydrates
  • Regeneration of ribulose bisphosphate (RuBP) – necessary to continue the cycle

C3, C4, and CAM Plants

  • C3 plants:
    • Initial CO2 fixation via rubisco produces 3-phosphoglycerate
  • C4 plants:
    • Minimize photorespiration via PEP carboxylase
    • Incorporate CO2 into four-carbon compounds in mesophyll cells
  • CAM plants:
    • Open stomata at night, fix CO2 into organic acids
    • Release CO2 during the day for use in the Calvin cycle

Photorespiration

  • A metabolic pathway that occurs when rubisco adds O2 instead of CO2 during carbon fixation in the Calvin cycle.
  • Consumes O2 and organic fuel.
  • Releases CO2 without producing ATP or sugar.
  • A wasteful process that can limit plant growth.

Oxidation and Reduction

  • Oxidation: loss of electrons
  • Reduction: gain of electrons
  • Oxidation-Reduction (redox) reactions are coupled.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

Photosynthesis CO5 PDF

Description

Explore the fundamental process of photosynthesis, where light energy is converted into chemical energy by plants. Learn about the key components involved, such as chloroplasts and the two stages of photosynthesis: light-dependent reactions and the Calvin cycle. This quiz will test your understanding of how plants synthesize organic molecules for energy and growth.

More Like This

Photosynthesis Overview Quiz
22 questions
Chloroplast en Fotosintese
5 questions

Chloroplast en Fotosintese

HighSpiritedTurtle avatar
HighSpiritedTurtle
Photosynthesis and Chloroplasts Overview
16 questions
Use Quizgecko on...
Browser
Browser