CHO
Carbohydrates (CHO) Study Guide
General Information
CHO are the most abundant biomolecules after water.
Plants: Serve structural and energy storage functions.
Animals: Primarily used as an energy source; stored energy plays a minor role.
Glycogen: Storage form of CHO in animals.
Non-ruminants: Main CHO source is starch.
Ruminants & Herbivores: Utilize starch, cellulose, and other non-starch polysaccharides.
Monosaccharides: All ketone and aldehyde sugars are monosaccharides.
Classification of Carbohydrates
Monosaccharides (Single sugar units): Glucose, fructose, galactose, mannose.
Disaccharides (Two sugar units): Lactose, sucrose, maltose.
Oligosaccharides (3-10 sugar units): Raffinose, stachyose, maltotriose, FOS, MOS, GOS.
Polysaccharides (>10 sugar units): Starch, cellulose, pectin, hemicellulose.
Sugar: Mono- or disaccharides in the diet.
Specific Carbohydrates
Dextrose: Another name for glucose.
Dextrins: Polymers of glucose from starch hydrolysis, containing alpha 1-4 and alpha 1-6 linkages.
Maltodextrin: A type of dextrin.
Dextran: Polymers of glucose with alpha 1-6 glycosidic linkages and branches from alpha 1-3 linkages.
Levulose: Another name for fructose.
Invert Sugar: A mix of glucose and fructose from enzymatically treated sucrose.
Structural and Chemical Properties
Carbohydrates are "hydrated carbons," with the smallest unit having 3 carbons.
Triose (3C): Glyceraldehyde (C3H6O3).
Tetrose (4C): Erythrose (C4H8O4).
Pentose (5C): Ribose, xylose, arabinose (C5H10O5).
Hexose (6C): Glucose, fructose, galactose (C6H12O6).
Monosaccharides
Major Sugars: Classified based on ketone or aldehyde groups.
Double Bonds: The key difference between aldehydes and ketones.
Ketone sugar examples: dihydroxyactetone, d-xylulose, d-ribulose, d-fructose, d-sedoheptulose
Aldehyde sugar: d-glycerose, d-erthrose, d-lyxose, d-xylose, d-arabinose, d-ribose, d-galactose, d-mannose, d-glucose
Aldehyde Sugars: Contain aldehyde groups at carbon 1.
Ketone Sugars: Contain a ketone group at carbon 2.
Aldehyde Sugars: Contain aldehyde groups at carbon 1.
Ketone Sugars: Contain a ketone group at carbon 2.
Disaccharides and Polysaccharides
Maltose: Glucose + glucose (alpha 1-4) → Digested by maltase.
Cellobiose: Glucose + glucose (beta 1-4) → Not digestible by animals.
Sucrose: Glucose + fructose (alpha 1-2) → Digested by sucrase.
Lactose: Galactose + glucose (beta 1-4) → Digested by lactase.
Starch: Composed of amylose and amylopectin.
Amylose: Alpha 1-4 linkages, water-soluble, easy to digest.
Amylopectin: Alpha 1-4 and alpha 1-6 linkages, insoluble, branched, harder to digest.
Glycogen: Found in animal liver/muscles, similar structure to amylopectin.
Cellulose: Provides plant rigidity, not digestible by animals but by bacteria.
Carbohydrates in Diet & Digestion
High Glycemic Index (GI): Rapid digestion → Insulin spikes → Fat deposition → Type II diabetes.
Low GI Foods (<55): Most fruits, vegetables, lentils.
Medium GI Foods (56-69): Brown rice, oatmeal, popcorn.
High GI Foods (>70): White bread, corn flakes, instant potatoes.
Resistant Starch (RS): Staw
This study guide summarizes key concepts related to carbohydrates, their structure, function, digestion, and impact on health.
Flashcards
Carbohydrates (CHO): Most abundant biomolecules after water.
CHO in Plants: Structural and energy storage functions.
CHO in Animals: Primary energy source; minor role in storage.
Glycogen: Storage form of carbohydrates in animals.
Non-Ruminant CHO Source: Mainly starch.
Ruminant & Herbivore CHO Source: Starch, cellulose, and other non-starch polysaccharides.
Monosaccharides: Single sugar units (glucose, fructose, galactose, mannose).
Disaccharides: Two sugar units (lactose, sucrose, maltose).
Oligosaccharides: 3-10 sugar units (raffinose, stachyose, maltotriose, FOS, MOS, GOS).
Polysaccharides: More than 10 sugar units (starch, cellulose, pectin, hemicellulose).
Sugar: Mono- or disaccharides in the diet.
Dextrose: Another name for glucose.
Dextrins: Polymers of glucose from starch hydrolysis.
Maltodextrin: A type of dextrin.
Dextran: Glucose polymers with alpha 1-6 and alpha 1-3 linkages.
Levulose: Another name for fructose.
Invert Sugar: Glucose and fructose mix from enzymatically treated sucrose.
Triose: 3-carbon sugar (glyceraldehyde).
Tetrose: 4-carbon sugar (erythrose).
Pentose: 5-carbon sugar (ribose, xylose, arabinose).
Hexose: 6-carbon sugar (glucose, fructose, galactose).
Aldehyde Sugars: Have an aldehyde group at carbon 1.
Ketone Sugars: Have a ketone group at carbon 2.
Maltose: Glucose + glucose (alpha 1-4 linkage).
Cellobiose: Glucose + glucose (beta 1-4 linkage).
Sucrose: Glucose + fructose (alpha 1-2 linkage).
Lactose: Galactose + glucose (beta 1-4 linkage).
Starch: Made of amylose and amylopectin.
Amylose: Alpha 1-4 linked glucose, water-soluble.
Amylopectin: Alpha 1-4 and alpha 1-6 linked glucose, branched.
Glycogen: Animal storage carbohydrate, similar to amylopectin.
Cellulose: Provides plant rigidity, not digestible by animals.
Glycemic Index (GI): Measures the speed of carbohydrate digestion.
High GI Foods: Rapid digestion, insulin spikes, potential obesity risk.
Low GI Foods: Slow digestion, includes most fruits and vegetables.
Resistant Starch (RS): Starch that escapes digestion in the small intestine.
SCFA Production: Short-chain fatty acids support gut health and energy.
Prebiotics: Non-digestible food ingredients promoting gut bacteria.
Probiotics: Live microorganisms beneficial for gut health.
Anti-Nutritional Oligosaccharides: Reduce digestibility (raffinose, stachyose).
Homopolysaccharides: Single sugar type (starch, cellulose).
Heteropolysaccharides: Multiple sugar types (hemicellulose, pectin).
Soluble Fiber: Dissolves in water, slows digestion.
Insoluble Fiber: Does not dissolve in water, speeds up digestion.