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31 Cards in this Set
- Front
- Back
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What is the difference between constitutional and stereoisomers?
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Constitutional - bonding sequence
Stereoisomers - arrangement of atoms in space 1. achiral or cis/trans (geometric isomers) 2. chiral (enantiomers or diastereomers) enantiomers and diastereomers are examples of optic isomers which rotate the plane of plane polarized light |
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What are enantiomers?
1. Definition & Properties 2. Examples |
1. "non-superimposable" (rotate by 180 and they are the same), have identical chemical and physical properties except their effect on plane polarized light and their reaction with other chiral molecules
2. Left and right hands, D, L Alanine, +/- Lactic Acid (- = sour milk, + = muscles), asparagine (bitter and sweet), and Limeonene (lemon and orange) |
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What are Diastereomers?
1. Definition & Properties 2. Examples |
1. 2 or more stereoisomers have different configurations
epimers - when 2 diastereomers differ from each other at only 1 stereoisomer 2. D-Threose and D-Erythrose, |
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What is a racemic mixture or racemate?
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equimolar mixture of two enantiomers
optically inactive |
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What are examples of Optically active and inactive compounds?
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Active:
2-Chlorobutane 3-methylhexane 1-chloro-3-methylpentane Inactive: Propanol 1-chlorobutane butanone |
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Importance of optical isomerism?
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many drugs are optically active, with only one enantiomer having the beneficial effect, the other enantiomer can be harmful
Example: thalidomide S thalidomide is dangerous and R thalidomide is effective the body racemises each enantiomer so even pure S is dangerous as it converts to R in your body thalidomide was given to pregnant women for motion sickness, led to many disabilities in babies and early deaths |
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What are oxidation and reduction?
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oxidation - increase in oxygen or decrease hydrogen, remove electrons
reduction - decrease oxygen or increase hydrogen, add electrons |
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What are some basic properties of carbohydrates, lipids, and proteins?
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carbohydrates:
4 kcal/gm 60-70 % energy preferred fuel (structure of CT) ex. glucose, ribose and deoxyribose, glycoprotein in hormones, glycolipid in nervous tissue, proteoglycan in mucous secretion, glucuronic acid in detox Lipid: 9 kcal/gm concentrated fuel substance Protein: tissue building material enzymes, antibodies, carrier molecules etc |
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What is the definition of Carbohydrates and some names?
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Empirical formula: Cn(H2O)m
Saccharide: simplest member monosaccharides - w/aldehyde = aldoses w/ketone = ketoses |
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What are examples of Mono, Di, Oligo, and Polysaccharides?
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Monosaccharide - CnH2nOn or Cn(H2O)n
Triose, Tetrose, Pentose (most abundant), Hexose (most abundant), Heptose Disaccharide - Cn(H2O)n-1 sucrose (glucose + fructose) maltose (glucose + glucose) lactose (glucose + galactose) Oligosaccharide [3-10 sugar units] stacchyrose raffinose Polysaccharide [>10 sugar units] starch glycogen cellulose hyaluronic acid heparin (anti-coagulant) |
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What are the types of Isomerism?
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1. Functional isomerism - diff. functional group
ex. aldose (glucose) and ketose (fructose) 2. Stereoisomerism - differ around penultimate C ex. D (naturally occuring and normally metabolized) and L (rare, NOT metabolized, present in toxins and antibiotics) 3. Anomerism - C bonded w/ functional group is anomeric ex. alpha (OH on right, below, or axial) and Beta (OH on left, above, or equatorial) Glucose in solution - more than 99 % in pyranose form, Beta-D-Glucopyranose (62 %) most abundant form of glucose in blood) 4. Optical Isomerism - differ in optical activity ex. d(+)[clockwise] and l(-)[anticlockwise] mutarotation - change in specific rotation that accompanies equilibrium of anomers (not poly) 5. Epimerism - differ around single asymmetric carbon ex. glucose and galactose at C4, glucose and mannose at C2 epimerase enzyme - interconverts these epimers |
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How are Glycosides formed?
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monosaccharide + alcohol = hemiacetal and then acetal
cyclic acetal = glycoside |
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How are Alditols formed?
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when a carbonyl group is reduced to hydroxyl group
sorbitol is found in the plants, 60 % as sweet as sucrose and used as sugar substitute for diabetics 3 other common alditols: Erythritol, Mannitol, Xylitol Sorbitol is responsible for early cataract in Diabetes Mellitus |
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How are Aldonic Acids formed?
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formed by oxidation of an aldehyde group to carbohydrate anion called aldonic acid
reaction is basis for determination of sugar in blood and urine Human blood contains 65-110 mg of glucose/ 100 mL of blood examples of reducing sugars: glucose, fructose, lactose, and maltose |
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What is a Spectrophotometer?
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measures the concentration of colored oxidation product
proportional to concentration of glucose |
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How is Uronic Acid formed?
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oxidation of terminal CH2OH group
oxidation of D-Glucose yields D-Glucuronic Acid important in acidic polysaccharides of CT in humans used by body to detoxify foreign phenols and alcohols; in liver these compounds are converted to glycosides of glucuronic acid and excreted in the urine |
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How do you form Phosphoric Esters?
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esters: acid + alcohol
mono and diphosphoric esters are intermediates in metabolism of monosaccharides ex. 1st step of glycolysis: D-glucose --> alpha-D-glucose 6-phosphate |
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What is a glycosidic bond?
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condensation of -OH group of the anomeric carbon of one sugar and an -OH group at any position on another sugar
ex C1-C4 (1-->4 Linkage) |
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What are some properties of sucrose?
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alpha-1,2 Glycosidic bond (C1 of glucose and C2 of fructose)
table sugar, present in fruits and honey, sugar cane, and beet sugar non-reducing sugar |
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What are some properties of Lactose?
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beta-1,4 glycosidic bond (C1 of galactose and C4 of glucose)
milk sugar beta - oriented above plane of ring reducing sugar |
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What are some properties of Maltose?
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alpha-1,4 glycosidic bond
malt sugar reducing sugar alpha - below plane of ring |
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What are some properties of Starch?
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storage form of carbohydrate plants
polymer of only D-glucose 2 components: 1. amylose (20-25 %) - D-glucose residues linked with alpha-1,4 glycosidic bonds 2. Amylopectin (75-80 %) - 10,000 of residues linked by alpha 1,4; every 24-30 linked by alpha 1,6 |
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What are some properties of Glycogen?
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storage form of carbohydrate in animals, stored in liver and muscle
polymer of 10^6 glucose units, branches every 8-10 units total amount in body = 350 grams |
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What are some properties of cellulose?
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found in nature as plant skeletal to impart strength and rigity
cotton = cellulose linked by beta-1,4 glycosidic bonds humans cannot ingest due to lack of enzyme to split beta bonds |
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What are Acidic Polysaccharides?
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contain carboxyl and/or sulfuric ester groups
impt in structure and function of CT collagen is made up of variety of acidic polysaccharides |
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What is Hyaluronic Acid?
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simplest acid polysaccharide
most abundant in embryonic tissues and specialized CT such as synovial fluid and the vitreous of the eye |
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What is Heparin?
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synthesized and stored in mast cells
used as anticoagulent, strongly binds to antithrombin III |
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What is Galactosemia?
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child unable to utilize galactose due to defective enzyme
milk contains glucose + galactose (lactose), cannot drink milk |
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What is Lactose Intolerance?
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inability to metabolize lactose due to lack of enzyme lactase
may cause gas, cramps, bloating |
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What are some characteristics of blood groups?
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discovered by Karl Landsteiner
type of blood group depends on type of trisaccharide or tetrasaccharide bound to surface of RBC only have antigens to blood type someone has, blood transfusion of a different type of blood will cause fatal immunological reactions Type A example: N-Acetyl-D-galactosamine --> N-Acetyl-D-glucosamine Type B example: D-Galactose --> N-Acetyl-D-Glucosamine |
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What are properties of each blood group?
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O group: universal donor, can only accept O
AB group: universal recipient, can donate to only AB A type: can accept A or O, can donate to A or AB B type: can accept B or O, can donate to B and AB |
