
Concept explainers
(a)
Interpretation: To indicate whether lactate is involved in (1) the pentose phosphate pathway, (2) the Cori cycle, (3) glycolysis, or (4) lactate fermentation.
Concept introduction: The pentose phosphate pathway is defined as the metabolic pathway in which NADPH,
Glucose is converted to pyruvate by glycolysis metabolic pathway; pyruvate is further converted to lactate in the skeletal muscle cells by anaerobic reactions. The lactate is diffused into the bloodstream, by which it is transported to the liver. Lactate is reconverted to pyruvate. Gluconeogenesis metabolic pathway uses this pyruvate to synthesize glucose in the liver cells. Glucose is diffused into the bloodstream and is transported back to the active skeletal muscle cells. This cycle is known as the Cori cycle.
Glycolysis is the metabolic pathway that breaks down a glucose molecule and converts it into two pyruvate molecules along with the production of two ATP molecules and NADH coenzymes.
Fermentation is defined as the biochemical anaerobic process by which NADH is oxidized to
The structure of lactate is as follows:
(a)

Answer to Problem 13.105EP
Lactate is associated with (2) the Cori cycle and (4) the lactate fermentation.
Explanation of Solution
An overview of the Cori cycle is as follows:
Lactate is converted to pyruvate in the liver. Therefore, lactate is associated with the Cori cycle.
Pyruvate is converted to lactate under oxygen-poor conditions by lactate dehydrogenase enzymes in the human body. This anaerobic reduction of pyruvate to form lactate by enzymes is called lactate fermentation. The
Therefore, lactate is associated with the Cori cycle and the lactate fermentation.
(b)
Interpretation: To indicate whether
Concept introduction: The pentose phosphate pathway is defined as the metabolic pathway in which NADPH,
Glucose is converted to pyruvate by glycolysis metabolic pathway; pyruvate is further converted to lactate in the skeletal muscle cells by anaerobic reactions. The lactate is diffused into the bloodstream, by which it is transported to the liver. Lactate is reconverted to pyruvate. Gluconeogenesis metabolic pathway uses this pyruvate to synthesize glucose in the liver cells. Glucose is diffused into the bloodstream and is transported back to the active skeletal muscle cells. This cycle is known as the Cori cycle.
Glycolysis is the metabolic pathway that breaks down a glucose molecule and converts it into two pyruvate molecules along with the production of two ATP molecules and NADH coenzymes.
Pyruvate is converted to lactate under oxygen-poor conditions by lactate dehydrogenase enzymes in the human body. This anaerobic reduction of pyruvate to form lactate by enzymes is called lactate fermentation.
Nicotinamide adenine dinucleotide is associated with the
(b)

Answer to Problem 13.105EP
Explanation of Solution
An overview of the Cori cycle is as follows:
In the Cori cycle,
Pyruvate is converted to lactate under oxygen-poor conditions by lactate dehydrogenase enzymes in the human body. This anaerobic reduction of pyruvate to form lactate by enzymes is called lactate fermentation. The chemical reaction for the formation of lactate is as follows:
In the lactate fermentation, NADH is oxidized to
The net overall equation for the glycolysis process is as follows:
(c)
Interpretation: To indicate whether
Concept introduction: The pentose phosphate pathway is defined as the metabolic pathway in which NADPH,
Glucose is converted to pyruvate by glycolysis metabolic pathway; pyruvate is further converted to lactate in the skeletal muscle cells by anaerobic reactions. The lactate is diffused into the bloodstream, by which it is transported to the liver. Lactate is reconverted to pyruvate. Gluconeogenesis metabolic pathway uses this pyruvate to synthesize glucose in the liver cells. Glucose is diffused into the bloodstream and is transported back to the active skeletal muscle cells. This cycle is known as the Cori cycle.
Glycolysis is the metabolic pathway that breaks down a glucose molecule and converts it into two pyruvate molecules along with the production of two ATP molecules and NADH coenzymes.
Pyruvate is converted to lactate under oxygen-poor conditions by lactate dehydrogenase enzymes in the human body. This anaerobic reduction of pyruvate to form lactate by enzymes is called lactate fermentation.
(c)

Answer to Problem 13.105EP
Explanation of Solution
The first stage of the pentose phosphate pathway is the oxidative stage. In the oxidative stage (involves three steps) of the pentose phosphate pathway,
The general equation for the entire pentose phosphate pathway is as follows:
Therefore,
The net overall equation for the glycolysis process is as follows:
Glucose enters the glycolysis metabolic pathway in the form of
(d)
Interpretation: To indicate whether
Concept introduction: The pentose phosphate pathway is defined as the metabolic pathway in which NADPH,
Glucose is converted to pyruvate by glycolysis metabolic pathway; pyruvate is further converted to lactate in the skeletal muscle cells by anaerobic reactions. The lactate is diffused into the bloodstream, by which it is transported to the liver. Lactate is reconverted to pyruvate. Gluconeogenesis metabolic pathway uses this pyruvate to synthesize glucose in the liver cells. Glucose is diffused into the bloodstream and is transported back to the active skeletal muscle cells. This cycle is known as the Cori cycle.
Glycolysis is the metabolic pathway that breaks down a glucose molecule and converts it into two pyruvate molecules along with the production of two ATP molecules and NADH coenzymes.
Pyruvate is converted to lactate under oxygen-poor conditions by lactate dehydrogenase enzymes in the human body. This anaerobic reduction of pyruvate to form lactate by enzymes is called lactate fermentation.
(d)

Answer to Problem 13.105EP
Explanation of Solution
The first stage of the pentose phosphate pathway is the oxidative stage. In the oxidative stage (involves three steps) of the pentose phosphate pathway,
The first step of the second stage i.e. the non-oxidative stage of the pentose phosphate pathway is the isomerization of
Want to see more full solutions like this?
Chapter 13 Solutions
Organic And Biological Chemistry
- Understanding the general acid-base properties of amino acids O Proteins Imagine each of the molecules shown below was found in an aqueous solution. Can you tell whether the solution is acidic, basic, or neutral? molecule The solution is... 010 H3N-CH-C-OH CH HO CH3 O acidic O basic neutral O (unknown) H3N HO 0 O acidic O basic neutral ○ (unknown) H3N-CH-C-O CH2 CH3-CH-CH3 O acidic O basic Oneutral ○ (unknown) O= X H2N-CH-C-O CH3 CH CH3 acidic O basic O neutral ○ (unknown) ? 000arrow_forwardImagine each of the molecules shown below was found in an aqueous solution. Can you tell whether the solution is acidic, basic, or neutral? molecule 0=0 H3N-CH-C-o HO CH2 OH The solution is... O acidic O basic O neutral O (unknown) H₂N acidic O basic O neutral ○ (unknown) + H3N O OH O acidic O basic O neutral O (unknown) H2N-CH-C-O CH3 O acidic O basic neutral ○ (unknown) X ? olo HEarrow_forwardRecognizing ampli Draw an a amino acid with a methyl (-CH3) side chain. Explanation Check Click and drag to start drawing a structure. X Carrow_forward
- Write the systematic name of each organic molecule: structure name × HO OH ☐ OH CI CI O CI OH OHarrow_forwardく Check the box under each a amino acid. If there are no a amino acids at all, check the "none of them" box under the table. Note for advanced students: don't assume every amino acid shown must be found in nature. COO H3N-C-H CH2 HO CH3 NH3 O CH3-CH CH2 OH Onone of them Explanation Check + H3N O 0. O OH + NH3 CH2 CH3-CH H2N C-COOH H O HIC + C=O H3N-C-O CH3- - CH CH2 OH Х 2025 McGraw Hill LLC. All Rights Reserved. Terms of Use | Privacy Center Accesarrow_forwardWrite the systematic name of each organic molecule: structure HO-C-CH2-CH3 O -OH CH3-CH2-CH2-CH2-CH2-C-OH CH3 CH3-CH-CH2-C-OH Explanation Check S namearrow_forward
- theres 2 productsarrow_forwardDraw the major product of this solvolysis reaction. Ignore any inorganic byproducts. + CH3CH2OH Drawing Q Atoms, Bonds and Rings OCH2CH3 || OEt Charges OH 00-> | Undo Reset | Br Remove Done Drag To Pan +arrow_forwardDraw the major product of this SN1 reaction. Ignore any inorganic byproducts. CH3CO2Na CH3CO2H Drawing + Br Q Atoms, Bonds and Rings OAC Charges OH ОАс Na ဂ Br Undo Reset Remove Done Drag To Pan +arrow_forward
- Organic Functional Groups entifying positions labeled with Greek letters in acids and derivatives 1/5 ssible, replace an H atom on the a carbon of the molecule in the drawing area with a ce an H atom on the ẞ carbon with a hydroxyl group substituent. ne of the substituents can't be added for any reason, just don't add it. If neither substi er the drawing area. O H OH Oneither substituent can be added. Check D 1 Accessibility ado na witharrow_forwardDifferentiate between electrophilic and nucleophilic groups. Give examples.arrow_forwardAn aldehyde/ketone plus an alcohol gives a hemiacetal, and an excess of alcohol gives an acetal. The reaction is an equilibrium; in aldehydes, it's shifted to the right and in ketones, to the left. Explain.arrow_forward
- Chemistry for Today: General, Organic, and Bioche...ChemistryISBN:9781305960060Author:Spencer L. Seager, Michael R. Slabaugh, Maren S. HansenPublisher:Cengage LearningGeneral, Organic, and Biological ChemistryChemistryISBN:9781285853918Author:H. Stephen StokerPublisher:Cengage LearningOrganic And Biological ChemistryChemistryISBN:9781305081079Author:STOKER, H. Stephen (howard Stephen)Publisher:Cengage Learning,
- Chemistry In FocusChemistryISBN:9781305084476Author:Tro, Nivaldo J., Neu, Don.Publisher:Cengage LearningChemistry: Matter and ChangeChemistryISBN:9780078746376Author:Dinah Zike, Laurel Dingrando, Nicholas Hainen, Cheryl WistromPublisher:Glencoe/McGraw-Hill School Pub CoIntroduction to General, Organic and BiochemistryChemistryISBN:9781285869759Author:Frederick A. Bettelheim, William H. Brown, Mary K. Campbell, Shawn O. Farrell, Omar TorresPublisher:Cengage Learning




