Biochemistry: Electron Transport Chain & Glycolysis
50 Questions
6 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 produced during glycolysis when glucose is broken down?

  • Pyruvate (correct)
  • Acetyl-CoA
  • FADH2
  • NADH

    • How much ATP is generated from substrate-level phosphorylation during the Krebs cycle?

  • 6 ATP
  • 2 ATP (correct)
  • 0 ATP
  • 4 ATP

    • What is the total ATP yield from the complete aerobic oxidation of one molecule of glucose?

  • 40 ATP
  • 36 ATP
  • 32 ATP
  • 38 ATP (correct)

    • Which molecule enters the Krebs cycle after glycolysis and preparatory steps?

    <p>Acetyl-CoA</p> Signup and view all the answers

    How many ATP are produced via oxidative phosphorylation with 6 NADH in the cycle?

    <p>18 ATP</p> Signup and view all the answers

    What initiates the process of glycolysis?

    <p>Phosphorylation of glucose</p> Signup and view all the answers

    During which step does the splitting of fructose 1,6-bisphosphate occur?

    <p>Steps 4 and 5</p> Signup and view all the answers

    What is produced as a result of Step 6 in glycolysis?

    <p>1,3-bisphosphoglyceric acid</p> Signup and view all the answers

    How many pyruvates are formed at the end of glycolysis?

    <p>2</p> Signup and view all the answers

    What is the total number of ATPs generated during the energy payoff phase of glycolysis?

    <p>4 ATPs</p> Signup and view all the answers

    What is the entry source of energy in glycolysis?

    <p>Glucose</p> Signup and view all the answers

    How many ATPs are initially invested in the glycolysis process?

    <p>2</p> Signup and view all the answers

    Which molecules are interconvertible during glycolysis?

    <p>G3P and DHAP</p> Signup and view all the answers

    What is the net production of ATPs after the complete glycolysis process?

    <p>2 ATPs</p> Signup and view all the answers

    What form enters the second phase of glycolysis?

    <p>Both PGAL and DHAP</p> Signup and view all the answers

    What is the first step in the flow of electrons in the Electron Transport Chain?

    <p>Reduction of NAD to NADH</p> Signup and view all the answers

    Which complex is involved directly before the final reduction of oxygen to water?

    <p>Cyt a3</p> Signup and view all the answers

    Which term describes the process where a substance gains electrons?

    <p>Reduction</p> Signup and view all the answers

    What is the purpose of the Electron Transport Chain?

    <p>To facilitate the flow of electrons and produce ATP</p> Signup and view all the answers

    In which order does the flow of electrons occur within the Electron Transport Chain?

    <p>FMN, Q, Cyt b, Cyt c1, Cyt c, Cyt a, Cyt a3</p> Signup and view all the answers

    What is the primary function of ATP in cellular processes?

    <p>To act as a convenient energy carrier for anabolic reactions</p> Signup and view all the answers

    Which type of phosphorylation directly involves the transfer of a phosphate group to ADP?

    <p>Substrate level phosphorylation</p> Signup and view all the answers

    In terms of energy, how could ATP be compared to a highly flammable liquid?

    <p>Both provide energy quickly and are easy to ignite</p> Signup and view all the answers

    What is a characteristic of ATP that makes it an effective energy carrier?

    <p>It contains high-energy, unstable bonds</p> Signup and view all the answers

    Which mechanism of ATP generation is primarily associated with the electron transport chain?

    <p>Oxidative phosphorylation</p> Signup and view all the answers

    What process generates ATP in the energy-conserving stage of glycolysis?

    <p>Substrate-level phosphorylation</p> Signup and view all the answers

    How many molecules of ATP are generated during the energy-conserving stage of glycolysis?

    <p>2 ATP</p> Signup and view all the answers

    Which intermediate is directly involved in the transfer of high-energy phosphates to ADP?

    <p>1,3-diphosphoglyceric acid</p> Signup and view all the answers

    Which of the following molecules is NOT produced during the energy-conserving stage of glycolysis?

    <p>FADH₂</p> Signup and view all the answers

    What role does chlorophyll play in photophosphorylation?

    <p>It absorbs light energy and excites electrons.</p> Signup and view all the answers

    What is the final product of glycolysis after the energy-conserving stage?

    <p>Pyruvic acid</p> Signup and view all the answers

    During photophosphorylation, what happens to the electrons after they lose their energy?

    <p>They return to chlorophyll.</p> Signup and view all the answers

    Which process is similar to the proton gradient created during photophosphorylation?

    <p>Oxidative phosphorylation.</p> Signup and view all the answers

    What is the primary outcome of the flow of protons through ATP synthase in photophosphorylation?

    <p>Generation of ATP from ADP.</p> Signup and view all the answers

    In cyclic photophosphorylation, what occurs after electrons travel through the electron transport chain?

    <p>They return directly to their original position.</p> Signup and view all the answers

    What is the primary role of the electron transport chain in ATP generation?

    <p>To transfer electrons and build a proton gradient</p> Signup and view all the answers

    Which protein is responsible for synthesizing ATP in the presence of a proton gradient?

    <p>ATP synthase</p> Signup and view all the answers

    What is substrate-level phosphorylation primarily characterized by?

    <p>Direct transfer of a phosphate group to ADP</p> Signup and view all the answers

    Which compound is ultimately reduced at the end of the electron transport chain?

    <p>Oxygen</p> Signup and view all the answers

    How are high-energy phosphates typically generated for substrate-level phosphorylation?

    <p>From earlier substrate oxidation reactions</p> Signup and view all the answers

    What is the net ATP production from the glycolysis step of cell respiration?

    <p>2 ATP</p> Signup and view all the answers

    What is the main by-product produced in muscle cells when oxygen supply is inadequate during high activity?

    <p>Lactic acid</p> Signup and view all the answers

    How many ATPs are produced from the Krebs Cycle for each glucose molecule?

    <p>2 ATP</p> Signup and view all the answers

    What is the total ATP yield from aerobic cell respiration (including all steps) for one molecule of glucose?

    <p>38 ATP</p> Signup and view all the answers

    Which step of cell respiration involves converting pyruvate into acetyl-CoA?

    <p>Preparatory Step</p> Signup and view all the answers

    What happens to NAD+ during the oxidation process?

    <p>It is converted to NADH and gains one hydrogen atom.</p> Signup and view all the answers

    Which statement correctly describes oxidation?

    <p>It involves the loss of electrons and hydrogen atoms.</p> Signup and view all the answers

    What is the result of glucose being oxidized in glycolysis?

    <p>Pyruvic acid is formed and NAD+ is reduced.</p> Signup and view all the answers

    What is released to the environment when NAD+ is reduced to NADH?

    <p>One H+ ion.</p> Signup and view all the answers

    In redox reactions, which of the following statements is accurate?

    <p>Oxidation and reduction are coupled processes.</p> Signup and view all the answers

    Study Notes

    Electron Transport Chain (ETC)

    • Electron transport begins with the reduction of NAD to NADH, proceeding through various complexes.
    • Key components of the ETC include FMN, Q, Cyt b, Cyt c1, Cyt c, Cyt a, and Cyt a3.
    • The process culminates in the reduction of oxygen to water, facilitating ATP production.
    • Reduction: gaining electrons; Oxidation: losing electrons, as defined in the diagram.

    Glycolysis Overview

    • The glycolytic pathway serves as the primary energy source from glucose.
    • Begins with the investment of 2 ATPs to convert glucose into PGAL and DHAP.
    • Only PGAL enters the energy payoff phase, yielding 4 ATPs (net gain of 2 ATPs).

    Energy Investment Phase in Glycolysis

    • Initial phosphorylation of glucose starts glycolysis.
    • Conversion of glucose into fructose follows.
    • Fructose-6-phosphate is phosphorylated.
    • Fructose 1,6-bisphosphate splits into two 3-carbon intermediates: glyceraldehyde-3-phosphate and dihydroxyacetone phosphate.

    Energy Payoff Phase in Glycolysis

    • 3-carbon compounds are oxidized to form 1,3-bisphosphoglyceric acid; this reaction reduces NAD+ to NADH.
    • Production of 4 ATPs and formation of 2 pyruvates occurs in the final steps.

    Summary of Cellular Respiration Steps

    • Glycolysis splits glucose into pyruvate, initially requiring 2 ATPs and later generating a total output of 4 ATPs.
    • The preparatory step converts pyruvate to acetyl-CoA.
    • The Krebs Cycle generates ATP, NADH, and FADH2, providing 2 ATPs.
    • The Electron Transport Chain uses NADH and FADH2 to generate an additional 34 ATPs.

    ATP Yield from Aerobic Respiration of One Glucose Molecule

    • Total yield: 38 ATP is produced during aerobic oxidation.
    • Glycolysis contributes 2 ATP (substrate-level), along with 6 ATP from NADH.
    • Conversions of pyruvate into acetyl-CoA yield an additional 6 ATP from 2 NADH.
    • The Krebs Cycle contributes 2 ATP (GTP) and oxidative phosphorylation from 6 NADH (18 ATP) and 2 FADH2 (4 ATP).

    Oxidation-Reduction Reactions (Redox)

    • Energy from organic molecules is extracted through the transfer of hydrogen atoms to NAD+, leading to the production of NADH.
    • Each conversion from NAD+ to NADH releases an H+ to the environment.
    • Redox processes are crucial for cellular energy extraction, converting nutrients into energy-rich products.

    Photophosphorylation

    • Occurs during photosynthesis in light-dependent reactions.
    • Light energy excites chlorophyll electrons, initiating an electron transport chain.
    • The resulting energy is used to create a proton gradient, which drives ATP synthesis through ATP synthase.

    General Aspects of ATP Generation

    • ATP is a high-energy energy carrier, analogous to a highly flammable substance providing readily available energy.
    • Mechanisms of ATP generation include:
      • Oxidative or Electron Transport Level Phosphorylation
      • Substrate-level Phosphorylation
      • Photophosphorylation (specific to photosynthesis).

    Electron Transport Level Phosphorylation (ETLP)

    • Also known as oxidative phosphorylation; critical for ATP generation.
    • Electrons from NADH lead to proton transport across membranes, creating a gradient for ATP synthesis via ATP synthase.

    Substrate-Level Phosphorylation (SLP)

    • Direct transfer of high-energy phosphates from substrate to ADP generates ATP.
    • Examples of this process are evident in glycolysis, showcasing phosphate transfers necessary for ATP formation.

    Studying That Suits You

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

    Quiz Team

    Description

    Test your knowledge on the Electron Transport Chain and Glycolysis processes. This quiz covers key components, phases, and energy transformations involved in these vital biochemical pathways. Understand how NADH and ATP play crucial roles in cellular energy production.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser