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BIOCHEM
CARBOHYDRATES (PPT)
Term | Definition |
---|---|
carbohydrate | is a polyhydroxy aldehyde, a polyhydroxy ketone, or a compound that yields polyhydroxy aldehydes or polyhydroxy ketones upon hydrolysis. |
carbohydrate glucose | is a polyhydroxy aldehyde |
carbohydrate fructose | is a polyhydroxy ketone |
Monosaccharides | classified as aldose or ketose on the basis of the type of carbonyl present |
Disaccharides | are glycosides formed from the linkage of two monosaccharides It is crystalline and water soluble. |
Oligosaccharides | are carbohydrates that contain three to ten monosaccharide units |
Polysaccharides | are polymers in which monosaccharides are the monomers |
Superimposable mirror images | are images that coincide at all points when the images are laid upon each other |
Nonsuperimposable mirror images | are images where not all points coincide when the images are laid upon each other. |
chiral center | is an atom in a molecule that has four different groups bonded to it in a tetrahedral orientation |
chiral | A molecule that contains a chiral center is said to be |
chiral molecule | is a molecule whose mirror images are not superimposable |
Stereoisomerism | connected in the same way but are arranged differently in space. |
Enantiomers | have structures that are nonsuperimposable mirror images of each other |
Diastereomers | have structures that are not mirror images of each other |
Fischer projection formula | is a two-dimensional structural notation for showing the spatial arrangement of groups about chiral centers in molecules. |
chiral center (Carbon) | In a Fischer projection formula a _________________ is represented as the intersection of vertical and horizontal lines |
D and L system | used to designate the handedness of glyceraldehyde enantiomers. |
aldohexose | A six-carbon monosaccharide with an aldehyde functional group is an |
ketopentose | a five-carbon monosaccharide with a ketone functional group is a |
D-glucose | is the most abundant in nature and the most important from a human nutritional standpoint. |
D-Fructose | is biochemically the most important ketohexose. It is also known as levulose and fruit sugar. Tastes sweet, nutritious, and is an important component of human diet. (diabetes) (grape sugar) |
D-Galactose | Milk sugar Synthesize in human Used to differentiate between blood types Six membered cyclic form |
D-Ribose | 1. Part of RNA 2. Part of ATP 3. Part of DNA 4. Five membered cyclic form |
Alpha-form | -OH of C1 and CH2OH of C5 are on opposite sides |
Beta-form | -OH of C1 and CH2OH of C5 are on same sides |
pyranose | A cyclic monosaccharide containing a six-atom ring is called a |
furanose | one containing a five-atom ring is called |
Haworth projection formula | is a two-dimensional structural notation that specifies the three-dimensional structure of a cyclic form of a monosaccharide. |
Beta configuration | both of these groups point in the same direction |
Alpha configuration | the two groups point in opposite directions |
OH groups in the Haworth projection formula. | The specific identity of a monosaccharide is determined by the positioning of the other _____________________________. |
Five important reactions of monosaccharides | Oxidation to acidic sugars Reduction to sugar alcohols Glycoside formation Phosphate ester formation Amino sugar formation |
Oxidation | can yield three different types of acidic sugars depending on the type of oxidizing agent used: |
Oxidation to acidic sugars | The redox chemistry of monosaccharides is closely linked to the alcohol and aldehyde functional groups present in them. |
Reduction to sugar alcohols | The carbonyl group in a monosaccharide (either an aldose or a ketose) is reduced to a hydroxyl group using hydrogen as the reducing agent. |
glycoside | general name for monosaccharide acetals is |
glycoside | is an acetal formed from a cyclic monosaccharide by replacement of the hemiacetal carbon -OH group with an -OR group |
D-galactose and its derivatives. | The monosaccharides responsible for blood groups are |
Phosphate ester formation | The hydroxyl groups of a monosaccharide can react with inorganic oxyacids to form inorganic esters. |
Phosphate esters of various monosaccharides are | stable in aqueous solution and play important roles in the metabolism of carbohydrates. |
Amino sugar formation | one of the hydroxyl groups of a monosaccharide is replaced with an amino group |
important building blocks of polysaccharides | Amino sugars and their N-acetyl derivatives are |
disaccharide | Two monosaccharides can react to form |
glycosidic linkage | The bond that links the two monosaccharides of a disaccharide (glycoside) together is called |
Cellobiose | is produced as an intermediate in the hydrolysis of the polysaccharide cellulose |
Cellobiose contains | two b - D-glucose monosaccharide units linked through a b (1—4) glycosidic linkage |
Maltose | is produced whenever the polysaccharide starch breaks down, as happens in plants when seeds germinate and in human beings during starch digestion. |
maltose is made up of | two D-glucose units, one of which must be a-D-glucose. |
Lactose is made up of | b-D-galactose unit and a b-D-glucose unit joined by a b(1-4) glycosidic linkage. |
Lactose | is the major sugar found in milk |
Lactose intolerance | condition in which people lack the enzyme lactase needed to hydrolyze lactose to galactose and glucose. |
Lactase | hydrolyzes b(1-4) glycosidic linkages. |
Deficiency of lactase | can be caused by a genetic defect, physiological decline with age, or by injuries to intestinal mucosa. |
Sucrose | table sugar nonreducing sugar.ets. |
table sugar | The most abundant of all disaccharides and found in plants. It is produced commercially from the juice of sugar cane and sugar beets |
polysaccharide | is a polymer that contains many monosaccharide units bonded to each other by glycosidic linkages. |
homopolysaccharide | is a polysaccharide in which only one type of monosaccharide monomer is present. |
heteropolysaccharide | is a polysaccharide in which more than one (usually two) type of monosaccharide monomer is present. |
Starch | is a homopolysaccharide containing only glucose monosaccharide units - It is the energy-storage polysaccharide in plants |
Amylopectin | the other polysaccharide in starch, has a high degree of branching in its polyglucose structure |
Glycogen | like starch, is a polysaccharide containing only glucose units. -Liver cells and muscle cells are the storage sites for humans - ideal storage form for glucose |
Cellulose | Humans and animals don’t have enzymes that hydrolyze so humans can not digest because they have bacteria in their guts to hydrolyze ______________________. - It serves as dietary fiber in food readily absorbs water and results in softer stools. |
Chitin | Similar to cellulose in both function and structure it has a N-acetyl amino derivative of glucose to give rigidity to the exoskeleton s of crabs, lobsters, shrimp, insects, and other arthropods. |
Acidic polysaccharides | polysaccharides with a repeating disaccharide unit containing an amino sugar and a sugar with a negative charge due to a sulfate or a carboxyl group Hyaluronic acid Heparin |
Hyaluronic acid | Alternating residues of N-acetyl-b-D-glucosamine and D-glucuronic acid. Highly viscous - serve as lubricants in the fluid of joints and part vitreous humor of the eye |
Heparin | An anticoagulant-prevents blood clots. |
glycolipid | is a lipid molecule that has one or more carbohydrate (or carbohydrate derivative) units covalently bonded to it. |
glycoprotein | is a protein molecule that has one or more carbohydrate (or carbohydrate derivative) units covalently bonded to it. |
ALDONIC ACID | is a molecule similar to an aldose, except that aldehyde has been oxidized to a carboxylic acid. |
ALDARIC ACID | is a carbohydrate im which both terminal group, either alcohol or aldehyde have been oxidized to carboxylic acid. |
ALDURONIC ACID | is a carbohydrate containing both carboxylix and an aldehyde or ketone. Obtained by the oxidation.C |
ALDITOL | a alcohol group both on top and bottom |
BLOOD TYPE O | Universal Donor |
BLOOD TYPE AB | Universal Recipient |
HERMAN EMIL FISCHER | German chemist One of the early greats in organic chemistry, Made fundamental discoveries about carbohydrates, proteins, and other natural products. awarded the 2nd Nobel Prize in Chemistry |
The fifth and sixth carbon species is the | most common |
Achiral | molecule whose is mirror are superimposable. - Do not possess handedness. |
ALDOSES | Is a monosaccharide that an aldehyde functional group. polyhydro-oxyaldehyde |
KETOSE | Is a monosaccharide that contains a ketone functional group. Poluhydroxyketones |
L-glucose | is tasteless and the body cannot use it. |
DEXTROSE | Optically active d-glucose in aquarius solution. Rotaes plan polarized light to the right. Used in hospitals. 5% glucose solution |
BLOOD SUGAR | Blood contains glucose 70 to 100 milligrams per dl |
WALTER NORMAN HOWARD | british chemist |