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• Who is the author of the study material on biochemistry?

  Jairah-Len P. Macalling, RMT
• What are the main categories of properties of carbohydrates discussed?

  • Physical properties
  • Chemical properties
• What are the physical properties of carbohydrates mentioned?

  Appearance and solubility
• What types of carbohydrates are classified under appearance?

  Mono and disaccharides, starches, cellulose
• How do mono and disaccharides differ from higher carbohydrates in terms of solubility?

  Mono and disaccharides are soluble, while higher carbohydrates like cellulose are not
• What is the relative sweetness of common sugars and sugar substitutes?

  • Fructose: 100
  • Invert sugar: 75
  • Sucrose: 58
  • Glucose: 43
  • Maltose: 19
  • Galactose: 19
  • Lactose: 9.2
  • Sucralose: 4
  • Saccharin: 4
  • Acesulfame potassium: 4
  • Aspartame: 4
• What is the significance of reducing sugars in chemical properties?

  They form characteristic osazone crystals when heated with phenylhydrazine
• What does Moore's test indicate about reducing sugars?

  It turns yellow to orange and finally dark brown when heated with NaOH
• What reagents are used in Molisch's test?

  Alpha-naphthol and 95% ethyl alcohol with concentrated H$_2$SO$_4$
• What is the positive result of the Anthrone test?

  Blue or green color
• What does Seliwanoff's test differentiate?

  It differentiates aldoses from ketoses
• What is the positive result of Tollen's Phloroglucinol test?

  Red color for galactose
• What is the purpose of Bial's Orcinol-HCl test?

  To distinguish a pentose from a hexose
• What does Tauber's Benzidine test indicate?

  Presence of pentoses
• What is fermentation in the context of carbohydrates?

  Decomposition of carbohydrates by microorganisms
• What is the oxidation process for sugars?

  Oxidation of aldehyde group occurs in all sugars except sucrose
• What happens during the reduction of sugars?

  All sugars except sucrose undergo reduction forming products convertible into fats
• What is the role of the primary alcohol group in sugars?

  It makes sugars reactive with acids
• What is the process of digestion and absorption of carbohydrates?

  • Complex carbohydrates must undergo digestion
  • 60% of food ingested is complex carbohydrates
  • Starch and glycogen are fragmented into monosaccharides
  • Cellulose and pentosans are not digestible by humans
• What are the two main components of starch?

  Amylose and amylopectin
• How is starch hydrolyzed?

  By the action of amylolytic enzymes or acid
• What are the two classes of amylase?

  Alpha-amylases and beta-amylases
• Where are alpha-amylases found?

  In pancreatic and salivary juices
• What happens in the stomach regarding carbohydrate digestion?

  Little digestion occurs as gastric juice has no carbohydrate-splitting enzyme
• What completes the digestion of polysaccharides and disaccharides?

  Pancreatic amylase and disaccharidases hydrolyze them into monosaccharides
• Where are carbohydrates absorbed in the small intestine?

  In the jejunum
• What are the factors affecting the absorption of carbohydrates?

  • Glucose decreases absorption of galactose and xylose
  • Galactose decreases absorption of glucose
  • Phlorhizin inhibits glucose transport
  • Vitamins promote absorption of hexoses
  • Hyperglycemia affects absorption rates
  • Sprue inhibits carbohydrate passage in intestinal cells
• What happens during hyperglycemia?

  Increased sugar levels in the blood occur
• What is the effect of the liver and muscle on glucose?

  They convert glucose to glycogen
• What is the role of cellulase in digestion?

  It acts on cellulose, but its nutritive value is insignificant
• What is the significance of the glucose tolerance test (GTT)?

  It assesses how well the body clears carbohydrates from the blood
• How does the absorption of carbohydrates differ between oral and IV administration in sprue?

  Oral administration does not follow normal GTT, while IV administration does
• What is the role of carrier proteins in carbohydrate absorption?

  They facilitate the transport of carbohydrates across the epithelial cell membrane
• What is the relative rate of transport for glucose?

  100%
• What is the relative rate of transport for galactose?

  110%
• What is the relative rate of transport for fructose?

  43%
• What is the relative rate of transport for mannose?

  19%
• What is the relative rate of transport for pentoses?

  9%
• What are the veins of the gastrointestinal tract mentioned?

  Superior mesenteric veins, splenic veins, inferior mesenteric veins
• How does phlorhizin affect glucose transport?

  It inhibits glucose transport