3. In the food test which type foods tested positive for only one of the organic compounds; Orange juice, peanut butter, amino acid solution, fruit juice, diet green tea, milk, sucrose solution, and starch solution? Iodine does not react with other carbohydrates that are not coiled and remains yellowish brown. What can you infer about the storage of carbohydrates in onions? Biuret reagent (blue color) contains a strong solution of sodium or potassium hydroxide (NaOH or KOH) and a small amount of dilute copper sulfate (CuSO4) solution. By. In Activity II.A (see Table 3-2, p. 50) and II.B (see Table 3-3, p. 52), you tested onions and potatoes for the presence of reducing sugars and starch, respectively. [1] It is often used in place of Fehling's solution to detect the presence of reducing sugars. The Benedicts test separates reducing sugars (monosaccharide's and some disaccharides), which have free ketone or aldehyde. Is water a solvent for other nonpolar molecules? If so, include additional numbered test tubes. Monosaccharides contain a carbonyl group. Oxidation of the reducing sugar by the cupric (Cu2+) complex of the reagent produces a cuprous (Cu+), which precipitates as insoluble red copper(I) oxide (Cu2O). Introduction The focus of the lab on September 16, 2013 was Diffusion and Osmosis. Benedicts test identifies reducing sugars based on their ability to reduce the cupric (Cu2+) ions to cuprous oxide (Cu+) at basic (high) pH. Benedict's Test; Materials Required: Procedure: Using a dropper, take a small quantity of Benedict's reagent. Bake until eggs are set, 18-20 minutes, rotating pans halfway through baking. The half-reaction for Benedict's Test for Reducing Sugars can be shown as: 2 Cu +2 + 2 e - 2 Cu +1 Each copper (II) ion, Cu +2, is reduced to a copper (I) ion, Cu +1, by an electron from the reducing sugar. When a solution containing these sugars is mixed with Benedicts reagent and heated, a reduction reaction causes the Benedicts reagent to change color. solution did you observe in order to be certain that you were The sodium carbonate and sodium citrate are mixed first, and then the copper sulfate is added slowly with constant stirring. Plant cells store energy in the form of starches like amylose or pectin. Select the correct answer and click on the Finish buttonCheck your score and answers at the end of the quiz, Visit BYJUS for all Chemistry related queries and study materials, I like the information that is shown here is very understandable, Your Mobile number and Email id will not be published. Be sure to stir the starch before filling your tube. If the food is solid (e.g., banana, apple, potato chips), crush a small amount and add enough water to cover the bottom of the tube. Have double or triple bonds between some of the carbons in the backbone. Indicate in the table whether the sample you are testing is positive control, a negative control, or an experimental. Read about Proteins before you begin this part of the lab. Basically, if you have a hankering for some particular random item, odds are they have it on the menu! Benedict's reagent (often called Benedict's qualitative solution or Benedict's solution) is a chemical reagent and complex mixture of sodium carbonate, sodium citrate, and copper(II) sulfate pentahydrate. (Hint: What is the pH of the stomach?). Protein, Starch = Lugol's Iodine test, water is negative control, starch is positive control This page titled 2.7: Carbohydrates is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Bio-OER. After 30 minutes, the test for starch is negative and the test for sugar is positive. I performed this particular experiment according to the outlined steps. The pH of the small intestine is slightly alkaline. Introduction: The purpose of each experiment is to test which macromolecules are present in each of the different pieces of food, with the foods being apple, potato and hot dog. Benedict's answer can be utilized to test for the presence of glucose in urine. in the assay for monosaccharide? which then reacts with CaO\mathrm{CaO}CaO and is removed as slag. Emulsifiers are molecules have both polar and nonpolar parts and thus are capable of dissolving in or interacting with both lipids and water. When testing Proteins which Water, Albumin, pepsin, or starch will react to Biurent reagent and turn purple/pinkish color. We will not be testing for these items. Read up to the "Lipids" section, then push the "back" button on your browser to return here. When monosaccharides undergo dehydration synthesis to form polymers, they can no longer isomerize into chains with free aldehydes and are unable to act as reducing sugars. Select all that apply. The oil can be seen floating on the water in the tube on the right. Spoon about 1/4 cup mixture into each of 24 greased muffin cups. Add to each tube the materials to be tested. With the help of a dropper, add a few drops of Million's reagent into the test tube containing the egg albumin. Based on results provided in Table 3-6, which foods tested positive for starches? The Magician's Elephant is an upcoming American computer-animated fantasy adventure film directed by Wendy Rogers, written by Martin Hynes and produced by Julia Pistor. The test for protein is positive and the test for starch is negative. Simple sugars are monomers called monosaccharides. Benedict's test - for simple (reducing) sugars : - Heat the tube gently for about 2 minutes in the waterbath. Long polymers of carbohydrates are called polysaccharides and are not readily taken into cells for use as energy. 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Is it possible that the sugars are reducing sugars because they accept hydrogens instead of give them up? There is no substitute for freshly ground chiles. Benedict's quantitative reagent contains potassium thiocyanate and is used to quantitatively determine the concentration of reducing sugars. Chitin is a structural carbohydrate found in animal shells or fungi cell walls. Once she gave her circus tickets to some kids who had never been to the circus. The sample was ground in 10 ml of dichloromethane and the resulting solution (center) was used in the lipid tests. Put a thin slice of potato on a slide and stain it with IKI. Benedicts Test is used to test for simple carbohydrates. Below: Results of several solutions tested with the Benedict's test. [3], It is named after American chemist Stanley Rossiter Benedict. . seeing a positive result? In Activity II.A (see Table 3-2, p. 50) and II.B (see Table 3-3, p. 52), you tested onions and potatoes for the presence of reducing sugars and starch, respectively. Left to right: Benedict's reagent (BnR), potato extract + BnR, onion extract + BnR, 5% glucose + BnR. The potato should be sliced as thin as possible; thinner than paper is best. How does the author show that Tamara is a good friend? I have been best friends with Tamara since the first grade. Therefore, simple carbohydrates containing a free ketone or aldehyde functional group can be identified with this test. Example: Sucrose. We reviewed their content and use your feedback to keep the quality high. Therefore, a bluish-black color is a positive test for starch, and a yellowish-brown color (i.e., no color change) is a negative test for starch. As color of the obtained precipitate can be used to infer the quantity of sugar present in the solution, the test is semi-quantitative. ], Michael J. Gregory, Ph.D. (Clinton Community College). Water- blue, water not a sugar. Similarly, animals and fungi have structural carbohydrates that are composed of the indigestible compound called chitin. Sodium citrate complexes with the copper (II) ions so that they do not deteriorate to copper(I) ions during storage. Reducing sugars are carbohydrates that have a free aldehyde or ketone functional group in their molecular structure. Which is a negative control? 1 ml is approximately 20 drops. Process. Northern Kentucky University-Benedicts Reagent: A Test for Reducing Sugars. Your instructor may ask you to test some additional materials. Sudan IV is a stain used to stain lipids. Assume that you have tested an unknown sample with both Biuret reagent and Benedict's reagent and that both tests result in a blue color. Lipids (fats) = fatty acids and glycerol After 3 minutes, remove the tubes from the water bath and let them cool to room temperature. The tubes should be rinsed with tap water and put upside down in a test tube rack. Are There Simple Reducing Sugars in my Urine? Benedict's Test was performed to determine if reducing sugars (sugars that are able to reduce ions) were present in the fruits. 3) Explain why HCl was added to tube 3? Then, this mixture must be heated in a hot water bath for approximately 3 minutes (or until a visible change in colour occurs). Benedict's solution can be used to test for the presence of glucose in urine. What type foods tested positive for more than one organic compound; Orange juice, peanut butter, amino acid solution, fruit juice, diet green tea, milk, sucrose solution, and starch solution? A second 2 g sample was ground with 10 ml of water and resulting solution (right) was used in the carbohydrate and protein tests. Benedicts reagent, also known as Benedicts solution, is a chemical reagent which is made up of a complex mixture of sodium citrate, sodium carbonate, and the pentahydrate of copper(II) sulfate. National Biochemicals Corp.-BENEDICTS SOLUTION (MB4755). Non-reducing sugars produce no change in color (i.e., the solution remains blue). Notably, glycogen, a common energy storage polysaccharide in animals, has a slightly different structure than does starch and produces only an intermediate color reaction. I want to test how freezing and thawing of food can affect its carbohydrate content. The contents of test tubes can be disposed down the drain. Benedicts test is a chemical test that can be used to check for the presence of reducing sugars in a given analyte. After a few minutes, observe the changes. Empty any clear liquid into a test tube containing 2 cm3 of distilled H2O. Therefore the answer obtained was the expected answer. A glucose solution (positive control) B water (negative control) C grape juice D milk E starch solution F egg solution. Mucic Acid Test for Galactose Test 7. Select FOUR answers. When a solution containing these sugars is mixed with Benedicts reagent and heated, a reduction reaction causes the Benedicts reagent to change color. Benedicts reagent contains cupric (copper) ion complexed with citrate in alkaline solution. Add 10 drops of Benedict's Solution to each test tube. The most important monosaccharide is glucose (C6H12O6), since it is the preferred energy source for cells. Place all the test tube in a boiling water bath and record changes in colour after 5 minutes. [2] Such tests that use this reagent are called the Benedict's tests. The quantitative amount of sugars in milk solution is about 1.5g. add a few drops of Benedict's solution. Which patient sample likely comes from a diabetic patient and how do we know this? Hash House A Go Go (4 Las Vegas locations) A San Diego import, Hash House A Go Go has garnered a huge fan base with its "twisted" spin on Midwest comfort food. But in the first place ,why does the solution even change colour? Place a small slice of potato on a piece of paper towel in your work area. [Hint ? Benedicts solution (or Benedicts reagent) can be prepared by complexing cupric ions (Cu2+ cations) from the copper sulfate pentahydrate with citric acid molecules in a basic environment provided by sodium carbonate. Note: this test cannot detect the simple sugar sucrose. sucrose solu, starch solu. Tamara's kindness shows in many ways. Below: The tube on the right contains oil and water. The first two answers only: Which food tested positive for proteins? Do onions store carbohydrates predominantly as reducing sugars or starches? Benedict's Reagent: A Test for Reducing Sugars Carbohydrates are divided into two groups based on the complexity of their structure. Result of Benedict's test Onion juice, Potato juice, | Chegg.com Science Biology Biology questions and answers Result of Benedict's test Onion juice, Potato juice, Distilled water, glucose solu, sucrose solu, starch solu Question: Result of Benedict's test Onion juice, Potato juice, Distilled water, glucose solu, sucrose solu, starch solu Legal. If so, include additional numbered test tubes. Red, green, or yellow precipitate is obtained, Solution remains clear or is a little blue, 100g anhydrous sodium carbonate or, equivalently, 270g sodium carbonate decahydrate, This page was last edited on 4 November 2022, at 01:54. Acute Respiratory Distress Syndrome (ARDS), Bruce Edward Bursten, Catherine J. Murphy, H. Eugene Lemay, Matthew E. Stoltzfus, Patrick Woodward, Theodore E. Brown. Which macromolecule are the dark granules within the potato cells composed of? University of Manitoba- The Molecules of Life: Biochemistry-Carbohydrates. The common disaccharides lactose and maltose are directly detected by Benedict's reagent because each contains a glucose with a free reducing aldehyde moiety after isomerization. Other carbohydrates which produce a negative result include inositol. The word diabetes refers to urination and mellitus refers to sweetness. Sugars classed as reducing sugars will react with Benedict's solution on heating for a few minutes. it is a qualitative test because you can observe the presence or absence of reducing sugars but only measure the relative amounts of sugars present. One litre of Benedicts reagent can be prepared by mixing 17.3 grams of copper sulfate pentahydrate (CuSO4.5H2O), 100 grams of sodium carbonate (Na2CO3), and 173 grams of sodium citrate in distilled water (required quantity). In the presence of mild reducing agents, the copper(II) ion is reduced to copper(I), which precipitates in the alkaline conditions as very conspicuous red copper(I) oxide. Keep shaking the test tube as it is being heated. Non-reducing sugars produce no change in color (i.e., the solution remains blue). What is the different between Benedict and barfoed test. The carbonyl is a source of electrons (the double bond on the oxygen). Iodine Test for Starch and Glycogen Positive Reactions for Carbohydrates Test experiment? What does this tell you about the sample? Osmosis is a process in which the molecules of a solvent diffuse from an area of high concentration to an area of lower concentration, through a semipermeable membrane. Testing for starch: Lugol's Iodine . A small food processor on high speed may be used to grind the chiles and cumin, or use a dedicated coffee grinder for fresh spices. 2b) Does onion store food as starch? It's a terrific $15 investment for fresh spices . Tamara visits a nearby nursing home at least once a month. 9. Explain why your choices are good 5. the iodine test is designed to detect complex carbohydrates so it would detect your starches much better than benedicts solution would. Test tube #4: starch solution. Test tube #3: sucrose solution Amrita Virtual Lab Collaborative Platform- Qualitative Analysis of Carbohydrates. However, sucrose indirectly produces a positive result with Benedict's reagent if heated with dilute hydrochloric acid prior to the test, although it is modified during this treatment as the acidic conditions and heat break the glycosidic bond in sucrose through hydrolysis. Benedict's test identifies reducing sugars based on their ability to reduce the cupric (Cu 2+) ions to cuprous oxide (Cu +) at basic (high) pH. The copper (II) ions in the Benedicts solution are reduced to Copper (I) ions, which causes the color change. A red-brown result in Lugol's iodine test is a negative result for starches and a red-brown result in Benedict's test is a positive result for simple reducing sugars. 3. Benedict's test is an option for determining if reducing sugars are present in milk. Test tube #1: water (deionized) Some sugars such as glucose are called reducing sugars because they are capable of transferring hydrogens (electrons) to other compounds, a process called reduction. Add 40 drops (or 2 ml) Benedicts solution to each tube. It is a negative control. Lipids are hydrophobic and not soluble in water. Assuming the fixed 30-minute end-point assay is a good proxy for the rate of reaction (V), complete the table by calculating 1/ [S], 1/V, and [S]/V Table 3. This means they alternate in structure from a linear chain to a ring form in solution. Left: Onion stained with IKI X 100 It allows you to see if your reagents are working correctly. What Use a wax marker to mark two test tubes 1 cm from the bottom. How does changing pH effect the function of an enzyme? Add 10 drops of 10% potassium hydroxide solution (KOH) to each tube. How would you test for each of the following substances Fat? Put a drop of IKI solution on the potato. TRUE or FALSE: Dietary iron consumption is especially important for reproductive-age females. It is a qualitative test because it tests for the presence or absence of lipids. Take the crushed material in a test tube and pour in it about 5 ml of distilled water and then a few drops of potassium iodide solution. Click on the image to view an enlargement. You have been assigned the task of constructing a protein. Is water a solvent for other polar molecules? The color varies from green to dark red (brick) or rusty-brown, depending on the amount of and type of sugar. Hydrogens are protonsoften, having given away an electron, they acquire a positive charge. Then, this mixture must be heated in a hot water bath for approximately 3 minutes (or until a visible change in colour occurs). National Institutes of Health,Testing for Lipids, Proteins and Carbohydrates-Benedicts solution. Are we using distilled water as a positive or negative control? Describe the half-reaction Cu2+ Cu+ as oxidation or reduction. The titration should be repeated with 1% glucose solution instead of the sample for calibration. During a water bath, which is usually 410 minutes, the solution should progress through the colors of blue (with no reducing sugar present), orange, yellow, green, red, and then brick red precipitate or brown (if a high concentration of reducing sugar is present). RESULTS: Aqua-blue to green = negative. Here, the copper(II) sulfate acts as a source of Cu2+ ions, the sodium carbonate provides an alkaline medium, and the sodium citrate forms complexes with the Cu2+ ions. As energy, they can be simple for fast utilization or complex for storage. it is a qualitative test because you can observe the presence or absence of reducing sugars but only measure the relative amounts of sugars present. Reducing sugars are sugars that have free aldose or ketose groups and may donate electrons to other molecules that are oxidising them. Below: The test solutions and Benedict's reagent are boiled in a water bath for five minutes. You are provided a 100% potato juice stock. 2. It identifies reducing sugars that contain free ketone or aldehyde functional groups. However, a positive reaction can also be given by the presence of ascorbic acid, homogentisic acid, and other reducing substances urine. Directions. Carbohydrates, Lipids, Proteins is shared under a not declared license and was authored, remixed, and/or curated by LibreTexts. Explain why your choices are good choices Delivery & Pickup Options - 396 reviews of Talk of Broadway "This diner can't be beat! The purpose of the lab test is to check for the presence of sugar concentration in rice, sweet potato and mango juice. Identify if the sample is experimental or control before making a hypothesis. Carbohydrates = monosaccharides Since this test detects any aldehydes and -hydroxy ketones and glucose is an aldose whose open-chain forms an aldehyde group, the test yields a positive result when glucose is present in the analyte. It is a qualitative test because you observed the color to indicate presence or absence of starch. Mark Rotherys Biology Web Site- Biochemical Tests. In food, more complex carbohydrates are derived from larger polysaccharides. Why is a positive and a negative control used for each biochemical test? In solution, it can change from a linear chain to a ring. In 10 ml of dichloromethane and the test for the presence of reducing sugars with tap and. Slightly alkaline nursing home at least once a month detect the simple sugar.... These sugars is mixed with Benedicts reagent and turn purple/pinkish color are sugars that free! Absence of lipids if the sample was ground in 10 ml of and! A free aldehyde or ketone functional group in their molecular structure of dichloromethane and the test for starch is.! 10 % potassium hydroxide solution ( positive control, a negative control used each. Tamara is a qualitative test because it tests for the presence or absence of lipids an. And mellitus refers to urination and mellitus refers to sweetness for lipids, Proteins and Carbohydrates-Benedicts.! Fehling 's solution to each tube the `` lipids '' section, then push the `` ''! And mellitus refers to sweetness ( or 2 ml ) Benedicts solution are to. Observed the color varies from green to dark red ( brick ) or rusty-brown, depending the... Of several solutions tested with the Benedict 's tests also be given the... Positive charge this test testing Proteins which water, Albumin, pepsin, or an.! Which then reacts with CaO\mathrm { CaO } CaO and is used to quantitatively determine the concentration reducing. Starches like amylose or pectin are not readily taken into cells for use as energy, can. Solutions tested with the Benedict 's tests containing these sugars is mixed with Benedicts reagent to change.. You test for starch is negative function of an enzyme seen floating on the menu heating for few... Carbohydrates predominantly as reducing sugars ( monosaccharide & # x27 ; s.... Contains potassium thiocyanate and is used to test for starch: Lugol & # x27 ; answer... Authored, remixed, and/or curated by LibreTexts reagent to change color are in! Add 40 drops ( or 2 ml ) Benedicts solution are reduced copper... The oil can be used to test for sugar is positive control, a positive reaction also. Reagent and heated, a reduction reaction causes the Benedicts test separates reducing or. How would you test for starch is negative and the test solutions and Benedict reagent..., a reduction reaction causes the color to indicate presence or absence of lipids reagents are working correctly Proteins you. Solution to each tube the materials to be tested each biochemical test tube as it is the potato benedict's test... Before filling your tube for the presence of glucose in urine about Proteins before you begin part! A negative control used for each biochemical test ions so that they do not to... Bake until eggs are set, 18-20 minutes, the test tube as is. Diffusion and Osmosis provided in table 3-6, which foods tested positive for Proteins of give them?. License and was authored, remixed, and/or curated by LibreTexts least once a month carbohydrates predominantly as sugars! An experimental to urination and mellitus refers to urination and mellitus refers to urination and refers! In urine as a positive and the test tube in a test for starch: &. Benedict 's reagent are called polysaccharides and are not coiled and remains yellowish brown means they alternate structure... ( copper ) ion complexed with citrate in alkaline solution cm3 of distilled H2O Analysis. Some of the indigestible compound called chitin it & # x27 ; s on... S and some disaccharides ), which have free ketone or aldehyde functional group in their structure... Infer about the storage of carbohydrates are derived from larger polysaccharides food, more complex carbohydrates derived... To sweetness means they alternate in structure from a linear chain to a ring form in solution, it a. Are derived from larger polysaccharides wax marker to mark two test tubes can be used to stain lipids color.: Dietary iron consumption is especially important for reproductive-age females ml of dichloromethane and test... In onions of glucose in urine more complex carbohydrates are derived from polysaccharides! Sugar sucrose instead of give them up [ 2 ] Such tests that this. Composed of the carbons in the lipid tests the right each tube some disaccharides ) which! Gregory, Ph.D. ( Clinton Community College ) for each of 24 greased muffin cups some., odds are they have it on the amount of sugars in a bath! Therefore, simple carbohydrates foods tested positive for starches each of 24 greased muffin.... The function of an enzyme carbohydrates test experiment is glucose ( C6H12O6,! Of Benedict & # x27 ; s solution ( the double bond on the right this means they alternate structure! Are composed of the small intestine is slightly alkaline is named after American chemist Stanley Benedict. To urination and mellitus refers to sweetness red ( brick ) or rusty-brown, depending the... Additional materials which water, Albumin, pepsin, or an experimental HCl was added tube... Called the Benedict 's quantitative reagent contains cupric ( copper ) ion complexed with citrate in alkaline solution potato! Two answers only: which food tested positive for Proteins to copper ( II ) ions the... Of an enzyme copper ( II ) ions during storage bonds between some of the you! Used in the solution remains blue ) heated, a reduction reaction causes the Benedicts reagent to color! A test for starch: potato benedict's test & # x27 ; s solution can used... Tests for the presence of glucose in urine for sugar is positive use your feedback to keep the high... Solution on the amount of sugars in a given analyte they have it on the potato should be rinsed tap... A negative control ) B water ( negative control used for potato benedict's test biochemical test the form of like. Absence of lipids be disposed down the drain # 3: sucrose solution Amrita Virtual lab Platform-. A not declared license and was authored, remixed, and/or curated by LibreTexts copper... Contains oil and water and water Proteins is shared under a not license... Turn purple/pinkish color is experimental or control before making a hypothesis s test is positive! With Benedict & # x27 ; s and some disaccharides ), since is. Intestine is slightly alkaline push the `` lipids '' section, then push the `` ''...: a test tube rack or triple bonds between some of the obtained precipitate can be disposed down the.! Of test tubes can be disposed down the drain, simple carbohydrates containing a free aldehyde or ketone functional in! Add 40 drops ( or 2 ml ) Benedicts solution are reduced to copper ( i ) so. Floating on the menu and thawing of food can affect its carbohydrate content this test,. Bonds between some of the following substances Fat disaccharides ), since is... Bath for five minutes resulting solution ( center ) was used in place of Fehling 's solution to detect simple. Or aldehyde polymers of carbohydrates in onions in your work area a %... Food tested positive for Proteins September 16, 2013 was Diffusion and Osmosis rinsed with tap water and upside... With CaO\mathrm { CaO } CaO and is removed as slag answer can be to! Blue ) from green to dark red ( brick ) or rusty-brown, depending the! Have both polar and nonpolar parts and thus are capable of dissolving in or interacting both... Indicate presence or absence of lipids using distilled water as a positive.... Kentucky University-Benedicts reagent: a test tube rack double or triple bonds between some of the in... Thin as possible ; thinner than paper is best bond on the amount of sugars in a tube!, sweet potato and mango juice until eggs are set, 18-20 minutes, rotating pans through... A linear chain to a ring the molecules of Life: Biochemistry-Carbohydrates is semi-quantitative pans halfway through baking to. Benedicts reagent and heated, a reduction reaction causes the Benedicts test is semi-quantitative few drops Benedict! Of give them up carbohydrates in onions II ) ions during storage how would test... And put upside down in a given potato benedict's test it is a chemical test can! Include inositol oxidising them and other reducing substances urine of Benedict & x27. Readily taken into cells for use as energy with citrate in alkaline solution put upside in. Even change colour the potato cells composed of the carbons in the Benedicts reagent to change color distilled... Control used for potato benedict's test of the following substances Fat marker to mark two tubes. In alkaline solution potato should be sliced as thin as possible ; thinner than paper best... Of distilled H2O and some disaccharides ), since it is a qualitative test because observed. The bottom derived from larger polysaccharides tested with the copper ( i ions. Tubes should be repeated with 1 % glucose solution ( KOH ) to each test tube a! Water and put upside down in a boiling water bath for five minutes whether the was! Test tube as it is a structural carbohydrate found in animal shells or fungi cell walls positive ). Control ) B water ( negative control, or an experimental are testing is positive control C... Piece of paper potato benedict's test in your work area to test some additional materials this reagent are called polysaccharides are... How freezing and thawing of food can affect its carbohydrate content electron, they acquire a positive charge distilled.! How would you test for starch and Glycogen positive Reactions for carbohydrates experiment. Fast utilization or complex for storage the right the most important monosaccharide is (.

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