Carbohydrates (CH 3.2) Flashcards
What are Carbohydrates?
- Hydrated carbons bc water & carbon are repeated multiple times
- A group of molecules that contain C,H, & O in a molar ratio of 1:2:1
- Empirical Formula is (CH2O)n where n= number of carbon atoms
- Many contain C-H bonds= release energy when oxidation occurs
What is the Simplest form of Carbos?
-Monosaccharides (simple sugars)
What are Monosaccharides?
- Simple sugars
- Can contain as few as 3 Carbon atoms to 6 or more= arranged in a ring form
- Those that have 6 carbon atoms= play a central role in energy storage
- Often used as building blocks to form larger molecules
What is the Monosaccharide that contains 3 Carbon atoms?
-Glyceraldehyde
What are the Monosaccharides that contain 5 Carbon atoms?
- Ribose
- Deoxyribose
What are the Monosaccharides that contain 6 carbon atoms?
- Glucose (most important for energy storage)
- Fructose (structural isomer that differs in the position of C-O double bonds)
- Galactose (Stereoisomer that differs in position of -OH & -H groups)
What are the characteristics of 6 Carbon Monosaccharides?
- EXIST in STRAIGHT CHAIN form but when they DISSOLVE in water they form RINGS
- Glucose is the most important for energy storage bc it has 7 C-H bonds
- Glucose can exist in Alpha or Beta
What is a Disaccharide?
- They’re made by linking 2 monosaccharides together
- Serve as transport molecules in plants & provide nutrition in animals
- Some are used to transport Glucose from one part to another
What do the Transport forms of Disaccharides depend on?
- Which monosaccharide are linked to form the Disaccharide
- Glucose can form transport disaccharides w/ itself or with other monosaccharides like fructose & galactose
How is Sucrose made & what is it’s purpose?
- When glucose links w/ fructose
- Sucrose is the form most plants use to transport glucose
How is Lactose made & what is it’s purpose?
- Glucose is linked w/ galactose
- Mammals use lactose to supply energy to their babie
What are Polysaccharides?
-Longer polymers that of course are made up of monomers, but those monomers have gone through dehydration reaction
What is Starch?
- Mixture of linear & branched polymers of Alpha-glucose subunits
- Found in plants that is composed of Amylose & Amylopectin
- Starch stores energy
How do organisms store metabolic energy contained in Monosaccharides?
-Convert them into Disaccharides like maltose and these are linked together into insoluable polysaccharides=Starches
What is the Starch with the simplest structure?
- Amylose! (linear)
- Each linkage of the Alpha Glucose occurs between C-1 of one glucose molecule to the C-4 of another= Alpha (1—->4) linkages
- The long chains coil up in water which makes amylose insoluable
What is Amylopectin?
- More complicated variation of Amylose
- They are BRANCHED polysaccharides with branches occuring between C-1 of one molecule & C-6 of another = Alpha (1—->6) linkages
- The amylose branches consist of 20-30 glucose subunits
- Also insoluable
What is Glycogen?
- Super BRANCHED of Alpha-glucose subunits
- Kinda like starch but it’s found in animals
- Has much longer average chain length & more branches than plant starch
- Stores energy & provides limited short term stored energy
What is Cellulose?
- Polymer of LINEAR Beta Glucose w/ the Beta (1—->4) linkages
- These long chains of Beta Glucose form tough fibers which makes Cellulose a key component in plant cell walls
- Beta Glucose bonds can’t be broken down by starch-hydrolizing enzymes bc those enzymes only recognize Alpha linkages
What is Chitin?
-Structural material found in anthropods & many fungi
-It’s a polymer of N-acetylglucosamine
(subsituted version of glucose)
- When its cross-linked by proteins, it forms a tough/ resistant surface= hard exoskeleton for insects & crustaceans
What is the function for Carbohydrates?
- Energy metabolism
- Components of cell to cell recognition molecules
- Components of complex carb polymers
What are Complex Carbohydrates?
- Large polymers of glucose
- Have same monomers but polymers are differentiated by the bonds between glucose & whether if its a branching or unbranching polymer
What are the 3 most important Complex Carbohydrates?
- Cellulose
- Starch
- Glycogen
How are Complex Carbohydrates formed?
-By dehydration synthesis
-What is the function for Carbohydrate Polymers?
-Structural & energy storage
So what are Macromolecules?
- Proteins
- Starches
- Lipids
- Carbs
What do the properties of Macromolecules determine?
-The taste, smell, nutrition, cooking properties, digestibility of our food & what mechs we use to digest it
What are people ACTUALLY allergic too when they say that they’re allergic to certain foods?
-They’re actually reacting to specific proteins in the food that makes them sick
