Cellular Respiration 2.6 U2 Flashcards
What is cellular respiration?
Process that cells use to release energy by breaking down glucose and other food molecules Composed of three main partsMost parts of cellular respiration require oxygen (which is why we need to breathe!)“Respiration”ALL cells must carry out some version of cellular respiration to have energy to live!Cells that live in anaerobic environments can only do the anaerobic parts!
What is aerobic?
requires oxygen
What is anaerobic?
does not require oxygen
What are the three stages of cellular respiration and are they anaerobic or aerobic?
GlycolysisAnaerobicKrebs CycleAerobicElectron Transport ChainAerobic
What is glycolysis?
“Sugar-breaking”Molecule of glucose is broken down into two molecules of pyruvic acidGlucose = 6 carbonsPyruvic acid (also called pyruvate) = 3 carbonsNeeds 2 ATP for the process to begin, and produces 4 ATPNET GAIN OF 2 ATP PER GLUCOSE MOLECULEAlso produces 2 NADH moleculesPasses 4 high energy electrons to NAD+NADH is used later in the electron transport chainOccurs in the cytoplasmAnaerobicDoes NOT require oxygen
What is glucose broken into
Molecule of glucose is broken down into two molecules of pyruvic acid
Does glycolysis require oxygen?
Does NOT require oxygenAnaerobic
Where does glycolysis occur
Occurs in the cytoplasm
How much ATP does glycolysis produce?
Needs 2 ATP for the process to begin, and produces 4 ATPNet 2 ATP
How much NADH molecules does glycolysis produce?
Also produces 2 NADH moleculesPasses 4 high energy electrons to NAD+NADH is used later in the electron transport chain
What are electron carriers?
Allow a cell to move electrons around as needed
What are the electron carriers involved in cellular respiration?
Ex. in cellular respiration: NADH and FADH2
Where is the mitochondria found?
Found in cytosol of the cell
What is a cristae?
Inner membrane has cristae (many inward protrusions)Increases surface area!
What is intermembrane space?
space between double membranes
What is the mitochondrial matrix?
compartment within inner membrane
Why is the multi-compartment structure important for the mitochondria?
helps keep reactions separate and maintain different molecule concentrations in certain areas
What is the Krebs Cycle(Citric Acid Cycle)
Pyruvate enters the mitochondriaPyruvate is first converted to acetyl-CoA in order to prepare for the cycleThis conversion produces 1 NADH and 1 molecule of CO2Occurs in mitochondrial matrixAcetyl-CoA (generated from pyruvic acid) is broken down into carbon dioxide in a series of energy-extracting reactionsCycle turns twice per original glucose molecule1 glucose = 2 pyruvateEach turn of cycle = 1 ATP producedPer glucose = 2 ATP producedAerobic, occurs in matrix
What is pyruvate turned into before krebs cycle?
Pyruvate is first converted to acetyl-CoA in order to prepare for the cycle
Where does the krebs cycle occur?
Occurs in mitochondrial matrix
How much NADH does the krebs cycle produce?
6 NADH
How much CO2 does the krebs cycle produce?
4 CO2
How much ATP does the krebs cycle produce?
2ATP
How much FADH does the krebs cycle produce?
2 FADH
What is the Electron Transport Chain(ETC)?
Series of electron carrier proteins that shuttle high-energy electrons during ATP-generating reactionsOxidative PhosphorylationElectron carriers were made in glycolysis & Krebs cycleNADH and FADH2ATP Synthase = generates ATP from ADPOccurs in inner mitochondrial membraneRegenerates electron carriersGenerates electrochemical gradient
What does ETC produce? How Much?
Produces water and ~32 ATP
What is ATP Synthase?
generates ATP from ADPWorks similarly to a water turbine in a power plantH+ ions instead of waterProcess is called chemiosmosis
Where does ETC occur?
Occurs in inner mitochondrial membrane
Where are electron carriers made that are used in ETC?
Electron carriers were made in glycolysis & Krebs cycle
What is chemiosmosis?
Energy stored in proton gradient used to do work
What is the chemical equation for cellular respiration?
C6H12O6 + 6O2 —> 6CO2 + 6H2O + ATP
What is anaerobic respiration?
Anaerobic Steps:GlycolysisFermentationLactic AcidEthanol/Alcohol
Where does anaerobic respiration occur?
Cytoplasm
What are the types of fermentation?
Alcohol Fermentation and Lactic Acid Fermentation
What is the goal of fermentation?
Allows you to continue to conduct glycolysis to generate those 2 ATP over and over again!Steady supply of ATPNowhere near as much energy as aerobic respiration, but better than nothing!
What is Alcoholic Fermentation?
Produces CO2 and Ethanol/Alcohol and NADHPyruvic acid + NADH —> Alcohol + CO2 + NAD+
hat is Lactic Acid Fermentation?
Produces Lactate and NADHPyruvic acid + NADH —> Lactic acid + NAD+
What are common uses for alcoholic fermentation?
Used to produce alcoholic drinks and biofuelProcess that causes bread to rise
What are common uses for Lactic Acid fermentation?
Food processing and preservation, such as pickles, sauerkraut, kimchi, yogurt, cured fish/meatsQuick bursts of energy for humans! (<90 s)
