Glycolysis energetics

Organisms, whether unicellular or multicellular, need to find ways of getting at least two key things from their environment: (1) matter or raw materials for maintaining a cell and building new cells and (2) energy to help with the work of staying alive and reproducing. Energy and the raw materials may come from different places. For instance, organisms that primarily harvest energy from sunlight will get raw materials for building biomolecules from sources like CO 2. By contract, some organisms rely on red/ox reactions with small molecules and/or reduced metals for energy and get their raw materials for building biomolecules from compounds unconnected to the energy source. Meanwhile, some organisms (including ourselves), have evolved to get energy AND the raw materials for building and cellular maintenance from sometimes associated sources. Glycolysis is the first metabolic pathway discussed in BIS2A; a metabolic pathway is a series of linked biochemical reactions. Because of its is centered on the processing of glucose for both energy extraction from chemical fuel and for the processing of the carbons in glucose into various other biomolecules (some of which are key precursors of many much more complicated biomolecules). We will therefore examine our study of glycolysisusing the precepts outlined in the energy challenge rubric that ask us to formally consider what happens to BOTH matter and energy in this multi-step process. Our investigation of glycolysis is a good oppo...

\( \newcommand\) • • • • • • • • • • • Learning Objectives • Briefly describethe function of glycolysis during aerobic respiration and indicate the reactants and products. • State whether or not glycolysis requires oxygen. • Compare where glycolysis occurs in prokaryotic cells and in eukaryotic cells. • State whether steps 1 and 3 of glycolysis are exergonic or endergonic and indicate why. • State why one molecule of glucose is able to produce two molecules of pyruvate during glycolysis. • Define substrate-level phosphorylation. • State the total number and the net number of ATP produced by substrate-level phosphorylation during glycolysis. • During aerobic respiration, state what happens to the 2 NADH produced during glycolysis. • During aerobic respiration, state what happens to the two molecules of pyruvate produced during glycolysis. Steps of Glycolysis • A phosphate from the hydrolysis of a molecule of ATP is added to glucose, a 6-carbon sugar, to form glucose 6-phosphate. • The glucose 6-phosphate molecule is rearranged into an isomer called fructose 6-phosphate. • A second phosphate provided by the hydrolysis of a second molecule of ATP is added to the fructose 6-phosphate to form fructose 1, • The 6-carbon fructose 1,6-biphosphate is split into two molecules of glyceraldehyde 3-phosphate, a 3-carbon molecule. • Oxidation and phosphorylation of each glyceraldehyde 3-phosphate produces 1,3-biphosphoglycerate with a high-energy phosphate bond (wavy red line) and NADH....

ATP Production per Glucose Molecule: Exploring the Energy Yield of Glycolysis During Glycolysis – What Is The Overall Gain Of ATP Per Glucose Molecule Glycolysis is a metabolic process that occurs in the cytoplasm of cells and is the first step in both aerobic and anaerobic respiration. The process breaks down glucose into pyruvate and produces ATP and NADH. In this article, we will explore the overall gain of ATP per glucose molecule during glycolysis. Overview of Glycolysis Glycolysis is a ten-step metabolic pathway that breaks down glucose into two molecules of pyruvate. The process produces two molecules of ATP, two molecules of NADH, and two molecules of water. The ATP produced during glycolysis is used as a source of energy for cellular processes. The first five steps of glycolysis are known as the preparatory phase. During this phase, glucose is phosphorylated twice and then split into two molecules of glyceraldehyde-3-phosphate. The next five steps of glycolysis are known as the payoff phase. During this phase, glyceraldehyde-3-phosphate is oxidized to pyruvate, and ATP is produced. Overall Gain of ATP per Glucose Molecule during Glycolysis The overall gain of ATP per glucose molecule during glycolysis is two molecules. However, four molecules of ATP are produced during glycolysis, and two molecules are consumed during the preparatory phase. This means that the net gain of ATP during glycolysis is two molecules per glucose molecule. The ATP produced during glycolys...

• Determine the amount of ATP produced by the oxidation of glucose in the presence and absence of oxygen. Determining the exact yield of ATP for aerobic respiration is difficult for a number of reasons. First of all, the number of ATP generated per reduced NADH or FADH 2is not always a whole number. For every pair of electrons transported to the electron transport chain by a molecule of NADH, between 2 and 3 ATP are generated. For each pair of electrons transferred by FADH 2, between 1 and 2 ATP are generated. In eukaryotic cells, unlike prokaryotes, NADH generated in the cytoplasm during glycolysis must be transported across the mitochondrial membrane before it can transfer electrons to the electron transport chain. Muscle and brain cells use a transport mechanism that converts theNADHin the cytoplasm into FADH2. In the liver, kidneys, and heart cells, a different transport mechanism is used, andNADHin the cytoplasm is convertedinto NADH in the mitochondria. As a result, different numbers of ATP molecules are generated from cytoplasmatic NADH in each tissue. For simplicity, however, we will look at the theoretical maximum yield of ATP per glucose molecule oxidized by aerobic respiration. We will assume that for each pair of electrons transferred to the electron transport chain by NADH, 3 ATP will be generated; for each electron pair transferred by FADH 2, 2 ATP will be generated. Keep in mind, however, that less ATP may actually be generated. In eukaryotic cells, the theo...

• Determine the amount of ATP produced by the oxidation of glucose in the presence and absence of oxygen. Determining the exact yield of ATP for aerobic respiration is difficult for a number of reasons. First of all, the number of ATP generated per reduced NADH or FADH 2is not always a whole number. For every pair of electrons transported to the electron transport chain by a molecule of NADH, between 2 and 3 ATP are generated. For each pair of electrons transferred by FADH 2, between 1 and 2 ATP are generated. In eukaryotic cells, unlike prokaryotes, NADH generated in the cytoplasm during glycolysis must be transported across the mitochondrial membrane before it can transfer electrons to the electron transport chain. Muscle and brain cells use a transport mechanism that converts theNADHin the cytoplasm into FADH2. In the liver, kidneys, and heart cells, a different transport mechanism is used, andNADHin the cytoplasm is convertedinto NADH in the mitochondria. As a result, different numbers of ATP molecules are generated from cytoplasmatic NADH in each tissue. For simplicity, however, we will look at the theoretical maximum yield of ATP per glucose molecule oxidized by aerobic respiration. We will assume that for each pair of electrons transferred to the electron transport chain by NADH, 3 ATP will be generated; for each electron pair transferred by FADH 2, 2 ATP will be generated. Keep in mind, however, that less ATP may actually be generated. In eukaryotic cells, the theo...

ATP Production per Glucose Molecule: Exploring the Energy Yield of Glycolysis During Glycolysis – What Is The Overall Gain Of ATP Per Glucose Molecule Glycolysis is a metabolic process that occurs in the cytoplasm of cells and is the first step in both aerobic and anaerobic respiration. The process breaks down glucose into pyruvate and produces ATP and NADH. In this article, we will explore the overall gain of ATP per glucose molecule during glycolysis. Overview of Glycolysis Glycolysis is a ten-step metabolic pathway that breaks down glucose into two molecules of pyruvate. The process produces two molecules of ATP, two molecules of NADH, and two molecules of water. The ATP produced during glycolysis is used as a source of energy for cellular processes. The first five steps of glycolysis are known as the preparatory phase. During this phase, glucose is phosphorylated twice and then split into two molecules of glyceraldehyde-3-phosphate. The next five steps of glycolysis are known as the payoff phase. During this phase, glyceraldehyde-3-phosphate is oxidized to pyruvate, and ATP is produced. Overall Gain of ATP per Glucose Molecule during Glycolysis The overall gain of ATP per glucose molecule during glycolysis is two molecules. However, four molecules of ATP are produced during glycolysis, and two molecules are consumed during the preparatory phase. This means that the net gain of ATP during glycolysis is two molecules per glucose molecule. The ATP produced during glycolys...

\( \newcommand\) • • • • • • • • • • • Learning Objectives • Briefly describethe function of glycolysis during aerobic respiration and indicate the reactants and products. • State whether or not glycolysis requires oxygen. • Compare where glycolysis occurs in prokaryotic cells and in eukaryotic cells. • State whether steps 1 and 3 of glycolysis are exergonic or endergonic and indicate why. • State why one molecule of glucose is able to produce two molecules of pyruvate during glycolysis. • Define substrate-level phosphorylation. • State the total number and the net number of ATP produced by substrate-level phosphorylation during glycolysis. • During aerobic respiration, state what happens to the 2 NADH produced during glycolysis. • During aerobic respiration, state what happens to the two molecules of pyruvate produced during glycolysis. Steps of Glycolysis • A phosphate from the hydrolysis of a molecule of ATP is added to glucose, a 6-carbon sugar, to form glucose 6-phosphate. • The glucose 6-phosphate molecule is rearranged into an isomer called fructose 6-phosphate. • A second phosphate provided by the hydrolysis of a second molecule of ATP is added to the fructose 6-phosphate to form fructose 1, • The 6-carbon fructose 1,6-biphosphate is split into two molecules of glyceraldehyde 3-phosphate, a 3-carbon molecule. • Oxidation and phosphorylation of each glyceraldehyde 3-phosphate produces 1,3-biphosphoglycerate with a high-energy phosphate bond (wavy red line) and NADH....

Organisms, whether unicellular or multicellular, need to find ways of getting at least two key things from their environment: (1) matter or raw materials for maintaining a cell and building new cells and (2) energy to help with the work of staying alive and reproducing. Energy and the raw materials may come from different places. For instance, organisms that primarily harvest energy from sunlight will get raw materials for building biomolecules from sources like CO 2. By contract, some organisms rely on red/ox reactions with small molecules and/or reduced metals for energy and get their raw materials for building biomolecules from compounds unconnected to the energy source. Meanwhile, some organisms (including ourselves), have evolved to get energy AND the raw materials for building and cellular maintenance from sometimes associated sources. Glycolysis is the first metabolic pathway discussed in BIS2A; a metabolic pathway is a series of linked biochemical reactions. Because of its is centered on the processing of glucose for both energy extraction from chemical fuel and for the processing of the carbons in glucose into various other biomolecules (some of which are key precursors of many much more complicated biomolecules). We will therefore examine our study of glycolysisusing the precepts outlined in the energy challenge rubric that ask us to formally consider what happens to BOTH matter and energy in this multi-step process. Our investigation of glycolysis is a good oppo...

• Determine the amount of ATP produced by the oxidation of glucose in the presence and absence of oxygen. Determining the exact yield of ATP for aerobic respiration is difficult for a number of reasons. First of all, the number of ATP generated per reduced NADH or FADH 2is not always a whole number. For every pair of electrons transported to the electron transport chain by a molecule of NADH, between 2 and 3 ATP are generated. For each pair of electrons transferred by FADH 2, between 1 and 2 ATP are generated. In eukaryotic cells, unlike prokaryotes, NADH generated in the cytoplasm during glycolysis must be transported across the mitochondrial membrane before it can transfer electrons to the electron transport chain. Muscle and brain cells use a transport mechanism that converts theNADHin the cytoplasm into FADH2. In the liver, kidneys, and heart cells, a different transport mechanism is used, andNADHin the cytoplasm is convertedinto NADH in the mitochondria. As a result, different numbers of ATP molecules are generated from cytoplasmatic NADH in each tissue. For simplicity, however, we will look at the theoretical maximum yield of ATP per glucose molecule oxidized by aerobic respiration. We will assume that for each pair of electrons transferred to the electron transport chain by NADH, 3 ATP will be generated; for each electron pair transferred by FADH 2, 2 ATP will be generated. Keep in mind, however, that less ATP may actually be generated. In eukaryotic cells, the theo...

\( \newcommand\) • • • • • • • • • • • Learning Objectives • Briefly describethe function of glycolysis during aerobic respiration and indicate the reactants and products. • State whether or not glycolysis requires oxygen. • Compare where glycolysis occurs in prokaryotic cells and in eukaryotic cells. • State whether steps 1 and 3 of glycolysis are exergonic or endergonic and indicate why. • State why one molecule of glucose is able to produce two molecules of pyruvate during glycolysis. • Define substrate-level phosphorylation. • State the total number and the net number of ATP produced by substrate-level phosphorylation during glycolysis. • During aerobic respiration, state what happens to the 2 NADH produced during glycolysis. • During aerobic respiration, state what happens to the two molecules of pyruvate produced during glycolysis. Steps of Glycolysis • A phosphate from the hydrolysis of a molecule of ATP is added to glucose, a 6-carbon sugar, to form glucose 6-phosphate. • The glucose 6-phosphate molecule is rearranged into an isomer called fructose 6-phosphate. • A second phosphate provided by the hydrolysis of a second molecule of ATP is added to the fructose 6-phosphate to form fructose 1, • The 6-carbon fructose 1,6-biphosphate is split into two molecules of glyceraldehyde 3-phosphate, a 3-carbon molecule. • Oxidation and phosphorylation of each glyceraldehyde 3-phosphate produces 1,3-biphosphoglycerate with a high-energy phosphate bond (wavy red line) and NADH....