Podcast
Questions and Answers
What is the primary energy source for brain cells and red blood cells?
What is the primary energy source for brain cells and red blood cells?
Where can glycogen be stored for later energy use?
Where can glycogen be stored for later energy use?
Which of these is a key function of carbohydrates in the body?
Which of these is a key function of carbohydrates in the body?
Which type of carbohydrate is primarily used for energy by brain cells?
Which type of carbohydrate is primarily used for energy by brain cells?
Signup and view all the answers
What happens to excess carbohydrates in the body?
What happens to excess carbohydrates in the body?
Signup and view all the answers
What is the anomeric carbon in aldoses?
What is the anomeric carbon in aldoses?
Signup and view all the answers
Which statement correctly describes the anomeric carbon?
Which statement correctly describes the anomeric carbon?
Signup and view all the answers
In ketoses, which carbon is considered the anomeric carbon?
In ketoses, which carbon is considered the anomeric carbon?
Signup and view all the answers
How is the anomeric carbon formed in monosaccharides?
How is the anomeric carbon formed in monosaccharides?
Signup and view all the answers
What distinguishes an anomer from other stereoisomers?
What distinguishes an anomer from other stereoisomers?
Signup and view all the answers
What is the initial step in the metabolism of sugars inside the body?
What is the initial step in the metabolism of sugars inside the body?
Signup and view all the answers
Which of the following intermediaries is NOT involved in glucose metabolism?
Which of the following intermediaries is NOT involved in glucose metabolism?
Signup and view all the answers
Which statement accurately reflects the role of Glu-6-P in metabolism?
Which statement accurately reflects the role of Glu-6-P in metabolism?
Signup and view all the answers
What happens to glucose after it is phosphorylated?
What happens to glucose after it is phosphorylated?
Signup and view all the answers
Which of the following statements is true regarding glucose intermediaries?
Which of the following statements is true regarding glucose intermediaries?
Signup and view all the answers
What is an epimeric carbon?
What is an epimeric carbon?
Signup and view all the answers
Which of the following sugars are recognized as epimers?
Which of the following sugars are recognized as epimers?
Signup and view all the answers
Which statement best describes epimers?
Which statement best describes epimers?
Signup and view all the answers
How many asymmetric carbons are present in glucose that can be classified as epimeric carbons?
How many asymmetric carbons are present in glucose that can be classified as epimeric carbons?
Signup and view all the answers
Which of the following is true about the relationship between glucose, galactose, and mannose?
Which of the following is true about the relationship between glucose, galactose, and mannose?
Signup and view all the answers
Which of the following compounds is an example of glucuronic acid?
Which of the following compounds is an example of glucuronic acid?
Signup and view all the answers
What is the result of reducing a carbonyl group?
What is the result of reducing a carbonyl group?
Signup and view all the answers
Which of the following structures signifies gluconic acid?
Which of the following structures signifies gluconic acid?
Signup and view all the answers
Which of the following statements is true regarding glucosaccharic acid?
Which of the following statements is true regarding glucosaccharic acid?
Signup and view all the answers
Which of the following correctly describes the structure of carbon compounds mentioned?
Which of the following correctly describes the structure of carbon compounds mentioned?
Signup and view all the answers
What is the color change that occurs when cupric ions react with sugar in Fehling's or Benedict's reagents?
What is the color change that occurs when cupric ions react with sugar in Fehling's or Benedict's reagents?
Signup and view all the answers
Which reagent is most commonly used to detect glucose in urine?
Which reagent is most commonly used to detect glucose in urine?
Signup and view all the answers
What is formed as a result of the reduction of cupric ions by sugar?
What is formed as a result of the reduction of cupric ions by sugar?
Signup and view all the answers
What type of ions does sugar reduce in Benedict's and Fehling's reagents?
What type of ions does sugar reduce in Benedict's and Fehling's reagents?
Signup and view all the answers
Which statement accurately describes the reaction between cupric ions and sugar?
Which statement accurately describes the reaction between cupric ions and sugar?
Signup and view all the answers
Study Notes
Biochemistry - Carbohydrate Chemistry
- Biochemistry is the chemistry of molecules found in living organisms, such as protein, lipids, nucleic acids, and carbohydrates.
- Carbohydrates are aldehyde or ketone derivatives of polyhydric alcohols, or substances derived from them.
- Carbohydrates make up about 60% of our diet.
- They're crucial for energy production (e.g., glucose—a major energy source for brain cells and red blood cells (RBCs).
- Glycogen can be stored in muscles and liver for later energy use.
- Carbohydrates provide fibers for intestinal motility and waste elimination.
- They also form glycolipids and glycoproteins involved in cell membrane structure and tissue cohesion.
- Important sources are starchy foods (e.g., potatoes, pasta, grains), vegetables, and milk products.
Carbohydrate Classification
- Monosaccharides (glycoses): Simplest carbohydrates; cannot be hydrolyzed into simpler forms. General formula is Cₙ(H₂O)ₙ.
- Disaccharides: Composed of two monosaccharide units joined by a glycosidic bond.
- Oligosaccharides: Contain 3-10 monosaccharide units.
- Polysaccharides: Contain more than 10 monosaccharide units.
Monosaccharide Naming
- I) By Functional Group:
- Aldoses: Contain an aldehyde group.
- Ketoses: Contain a ketone group.
- II) By Carbon Number:
- Triose: 3 carbon atoms
- Tetrose: 4 carbon atoms
- Pentose: 5 carbon atoms
- Hexose: 6 carbon atoms
- Heptose: 7 carbon atoms
- III) Combining I and II: Examples include aldotrioses, ketotrioses, aldopentoses, ketopentoses, etc.
Importance of specific monosaccharides
- Ribose and Deoxyribose: Components of nucleic acids (RNA and DNA), high-energy phosphate compounds, and coenzymes (NAD, NADP, flavoproteins).
- Glucose: The most abundant monosaccharide, primary source of energy for mammals.
- Fructose (Fruit Sugar): A common ketohexose found in fruits and honey; also a significant energy source.
- Galactose: Involved in lactose synthesis (milk sugar) and brain tissue structure.
- Mannose: A constituent of various glycoproteins.
Cyclic Structures
- Monosaccharides form cyclic structures in solution due to intramolecular reactions.
- The cyclic forms are more stable than the open-chain forms.
- The cyclic forms are pyranose (6-membered ring) and furanose (5-membered ring).
Isomerism in Carbohydrates
- Optical Activity: The ability of a molecule to rotate plane-polarized light.
- Asymmetric Carbon Atoms (Chiral Centers): Carbon atoms with four different groups attached.
- Optical Isomers (Enantiomers): Non-superimposable mirror images. E.g., D- and L- glyceraldehyde.
- Specific Rotation: The angle a substance rotates plane-polarized light at a specific concentration and temperature.
Nomenclature
- D and L Configurations: Important for classifying monosaccharides based on the arrangement of hydroxyl groups.
Sugar Derivatives
- Sugar Acids: Oxidation of the carbonyl or hydroxyl group in carbohydrates can produce acidic forms.
- Sugar Alcohols: Reduction produces alcohol forms.
- Deoxysugars: Replacement of a hydroxyl group with a hydrogen atom.
- Amino Sugars: sugars featuring amino groups .
- Synthesis of carbohydrates in the body: Glucuronic acid conjugation with insoluble molecules makes them soluble in water for detoxification purposes.
Glycosidic Bonds
- Glycosidic Bond: A bond between carbohydrates and other molecules, or another carbohydrate (e.g., to make disaccharides).
- O-glycosides: The bond to another sugar or aglycone (non-carbohydrate component) via an oxygen atom.
- N-glycosides: The bond is to an amino group of the aglycone.
- Naming Glycosidic bonds: Based on the position of involved carbon atoms and configuration of involved anomers.
Disaccharides
-
Maltose: Glucose + Glucose (α(1→4) linkage).
-
Isomaltose: Glucose + Glucose (α(1→6) linkage).
-
Lactose: Galactose + Glucose (β(1→4) linkage).
-
Sucrose: Glucose + Fructose (α(1→2) linkage).
-
Cellobiose: Glucose + Glucose (β(1→4) linkage).
-
Trehalose: Glucose + Glucose (α(1→1) linkage).
-
Invert Sugar: A mixture of glucose and fructose resulting from sucrose hydrolysis.
Polysaccharides
- Starch: A storage polysaccharide in plants; a mixture of amylose (unbranched) and amylopectin (branched).
- Glycogen: An animal storage polysaccharide; highly branched, more compact than amylopectin.
- Cellulose: The structural component of plant cell walls (β(1→4) glycosidic linkage).
- Inulin: A fructosan found in plant roots, important for medical diagnosis.
- Dextrans: Microbial polysaccharides, used as plasma substitutes.
Other important features
- GAGs (Glycosaminoglycans): Essential components of connective tissues.
- Proteoglycans: GAGs attached to proteins, play crucial roles in tissue support, lubrication, and cell signaling.
- Glycoproteins: Proteins with covalently attached carbohydrates, involved in various cellular functions like cell-cell recognition, signaling, and structure.
- Fibronectin: Important for cell adhesion, growth, and migration.
- Laminin: Essential for basement membrane formation and cell-matrix interactions.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Explore the essential role of carbohydrates in biochemistry. This quiz covers the classification, functions, and dietary importance of carbohydrates, including monosaccharides and disaccharides. Test your knowledge on how carbohydrates contribute to energy production and overall health.
