What is Glucose: Definition and 64 Discussions

Glucose is a simple sugar with the molecular formula C6H12O6. Glucose is the most abundant monosaccharide, a subcategory of carbohydrates. Glucose is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, using energy from sunlight, where it is used to make cellulose in cell walls, the most abundant carbohydrate in the world. In energy metabolism, glucose is the most important source of energy in all organisms. Glucose for metabolism is stored as a polymer, in plants mainly as starch and amylopectin, and in animals as glycogen. Glucose circulates in the blood of animals as blood sugar. The naturally occurring form of glucose is d-glucose, while l-glucose is produced synthetically in comparatively small amounts and is of lesser importance. Glucose is a monosaccharide containing six carbon atoms and an aldehyde group, and is therefore an aldohexose. The glucose molecule can exist in an open-chain (acyclic) as well as ring (cyclic) form. Glucose is naturally occurring and is found in fruits and other parts of plants in its free state. In animals, glucose is released from the breakdown of glycogen in a process known as glycogenolysis.
Glucose, as intravenous sugar solution, is on the World Health Organization's List of Essential Medicines, the safest and most effective medicines needed in a health system. It is also on the list in combination with sodium chloride.The name glucose derives through the French from the Greek γλυκός ('glukos'), which means "sweet", in reference to must, the sweet, first press of grapes in the making of wine. The suffix "-ose" is a chemical classifier, denoting a sugar.

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  1. mktsgm

    Glucose structure and insulin resistance

    I have a doubt about the process of type-2 diabetes. It is said that insulin resistance leads to type-2 diabetes. That would mean, even in the presence of insulin, the glucose uptake into the cells does not take place, leading to hyperglycemia. My doubt is, how could this happen in spite of...
  2. mktsgm

    Normally insulin levels are not measured in type-2 diabetes. Why?

    Type-2 diabetes patients generally display higher levels of glucose circulating in their blood. While type-1 is considered a lack of insulin disease, in type-2 it is considered that insulin may be present, but it is not working properly. It is called Insulin-resistance. Most of the drugs for...
  3. bo reddude

    Exploring the Math of Glucose Polymers: Understanding 6^n

    Let's say you have n glucose monomers. (C6H12O6) n You want to find out how many possible polymers exist in combining those n number of glucose molecules randomly. So glucose_1 has 6 OHs that can combine with glucose_2 which also has 6 OHs. Starting with glucose_1's first carbon C1, at that...
  4. P

    Biology Which organs/parts of the body are only functional on glucose?

    Hi everyone! Do you have an idea which organs/parts of the body are ONLY functional on glucose? I would say the brain, pancreas, liver and kidney, but I have to take into account only those organs that are ONLY functional on glucose
  5. L

    Approximating Glucose as an Ideal Gas: Can We Calculate Entropy?

    For now it is only about the 1 task If the task states that: You can approximate that their dynamics in water resembles that of an ideal gas. Does it then mean that I can take glucose as the ideal gas and then simply calculate the entropy for the ideal gas?
  6. N

    Medical Error measuring glucose optical sensor

    Hello We have designed an optical sensor to measure glucose. But we do not have the same changes for different concentrations. What do we need to do to be able to observe different Lifetime concentrations? In our sensor test, we used phosphorescence and glucose oxidase technology. The sensor...
  7. berkeman

    How are blood glucose monitoring modules installed in arms?

    My wife asked me a good question, and even with moderate Google searching I couldn't answer her question about how the patches are installed in arms. How do these BGL monitoring patches work? Thanks...
  8. duchuy

    Chemistry Methylation of glucose (mechanism)

    Hi, I don't understand why this correction would be a nucleophile substitution? From what understand : The O atoms in the cyclic glucose acts as nucleophiles. ICH3 is also a nucleophile due to the presence of iodine's "non bonding electron pairs" (sorry I don't know the right term for this), and...
  9. greg_rack

    Rotation of the plane of polarization of light by glucose

    Hi guys, Online I found this really cool experiment that uses a glucose solution(e.g. in a beaker) to rotate the plane of polarization of a polarized light beam passing through it, of an angle ##\theta## which depends on the frequency of the EM wave. Then, for example, watching white light...
  10. mktsgm

    Medical How are normal values of blood pressure and glucose determined?

    Blood glucose is measured and compared against a set of standard/normal values (like, fasting 100 mg/dL etc) to determine if a person has hyperglycemia or not. Similarly Blood pressure readings (systolic & diastolic) are also compared against another set of standard/normal values like 120/80...
  11. Harini Krishna

    Determination of the glucose content in hot beverages

    <mentor - moved to Engineering> Hi, I would like to know how the glucose content can be measuring in hot beverages using non-intrusive method. Thankyou
  12. F

    Differential equation modeling glucose in a patient's body

    The rate at which glucose enters the bloodstream is ##r## units per minute so: ## \frac{dI}{dt} = r ## The rate at which it leaves the body is: ##\frac {dE}{dt} = -k Q(t) ## Then the rate at which the glucose in the body changes is: A) ## Q'(t) = \frac{dI}{dt} + \frac {dE}{dt} = r - k...
  13. marcophys

    Can glucose combine with sodium bicarbonate?

    I fell upon an article outlining the general health benefits of a balanced pH, and specific anti cancer benefits. ... both concepts are well supported in published studies. The article then went on to describe a protocol, whereby sodium bicarbonate is dissolved in liquefied honey. The principal...
  14. physea

    Glucose and the Lymphatic System: A Complex Relationship

    Hello, Can you tell me please the glucose physiology in respect to the lymphatic system in short? Is there glucose inside the lymph? How does glucose enter/leaves the lymph? Are the glucose levels in blood related to the glucose levels in lymph? thanks!
  15. mktsgm

    Medical Is the Renal Threshold for Glucose Exceeded in Diabetic Patients?

    Hi, Wikipedia in its article on 'Glycosuria' says that the renal threshold for glucose (RTG) reabsorption in the kidney is around 160-180 mg/dL. Beyond which the glucose starts to excrete in the urine. But in diabetic people blood glucose exceeds in range of 300-400 mg/dL is prevalent. How this...
  16. Asmaa Mohammad

    Why Does the Fischer Projection of Glucose Show Carbon Atoms with Five Bonds?

    Hello, my book shows this figure of Fischer formula of D-glucose I don't understand this figure, and I wonder why the upper carbon atoms in both the right and left formulas have 5 bonds. And from where comes this hedrogen atom in the upper left side of the figure (attached to alpha...
  17. science_rules

    How to prepare 500 mL of 0.025 M of Glucose solution?

    Homework Statement : I am using a virtual chemistry laboratory and the directions for the first lab experiment says to prepare 500 mL of 0.025 M of glucose solution by diluting the 1 M glucose solution. (I am re-posting this question due to the fact that the previous one was deleted because it...
  18. i_hate_math

    What is enthelpy for combustion of glucose?

    The enthalpies of formation with reference to (2) are: ∆(Glucose)= −1,268 /, ∆(Carbon Dioxide)= −393.5 ./, ∆(water)= −285.8 /. How do I calculate the enthalpy for the combustion of 1 mole of glucose? I know H = U + PV and ∆H = Q + Wother, but I am confused by all the chemistry involved!
  19. mktsgm

    Medical Good Glucose vs. Bad Glucose: Is There a Difference?

    We have a good cholesterol (HDL) and bad cholesterol. It just occurred to me that do we have a similar thing in glucose too. Good glucose after a proper digestion and bad glucose in improper digestion?
  20. physea

    How Does a Glucose Sensor Work?

    Guys, how does blood glucose sensor works? I am particularly interested, how does glucose is adsorbed in the sensor, how does it converted into electric signal?
  21. mktsgm

    Medical Insulin dependent glucose uptake

    We know that type 2 diabetes is caused by insulin insufficiency/resistance. Normally Insulin causes GLUT4 in the liver and muscle/adipose cells to surface at their cell membrane, to facilitate the transport of glucose from the circulating blood. Type2DM lacks this action and hence glucose...
  22. E

    Glucose Heating w/ HI: Why Get N-Hexane? | Reaction Explanation

    Why does glucose on prolonged heating with HI give n-hexane? What mechanism/reaction type is this? All I knew till now was that alcohols would give halogen substituted products with hydrogen halides.
  23. CMATT

    Which of the following is/are true regarding glucose transport

    Homework Statement Which of the following is/are true regarding glucose transport to the brain? There could be multiple answers. a) Glucose uptake by the nerve cells of the brain is dependent on insulin b) Greater concentrations of glucose in the blood should increase the rate at which glucose...
  24. Stephanus

    Producing Methane from Sugar - PF Forum

    Dear PF Forum, Can anyone help me? I'd like to know what is the reaction that produces methane from sugar? I believe it's reduction. This is sugar oxydation: C6H12O6 + 6O2 -> 6CO2 + 6H2O What is the reaction to produce methane from glucose? C6H12O6 + ? -> CH4 + ? And please if you would be so...
  25. L

    Glucose Metabolism- correct or is my understanding flawed?

    I am trying to understand about glucose metabolism! I have been researching this stuff forever! X( Would you see if my explanations are right, and if not, tell my why? Thank you SO much! That would be a HUGE help! Is it true that uptake and release of gas/nutrients only occur in the...
  26. L

    Does glucose in its cyclic structure react with HI ?

    does glucose in its cyclic structure react with HI to form CH3-CH2-CH2-CH2-CH2-CH3? (open chain structure of glucose reacts with HI to form CH3-CH2-CH2-CH2-CH2-CH3)
  27. O

    Can Glucose Synthesis be Achieved Technically?

    Can this photo synthesis be done by technical means or is it only happen in plants? Synthesis: 6CO2 + 6H2O(gas) + sun radiation = C6 H12 O6(Glucose) + 6O2 Revers: (cellular respiration) C6 H12 O6(Glucose) + 6O2 = 6CO2 + 6H2O(gas) + caloric energy (deltaG) deltaG = -2880 kJ per mole...
  28. T

    3D Graphene foam from glucose by chemical blowing

    I'm a third year physics undergraduate and I want to make 3D Graphene - without spending a fortune. This is my background: I found this review article by Jiang and Fan (Design of advanced porous graphene materials: from graphene nanomesh to 3D architectures) to be very helpful. From what...
  29. S

    How does exercise accelerate glucose uptake in diabetes?

    We're usually just told that exercise is a great way to stimulate the movement of glucose into cells. But how does it do that? I would think that insulin resistance is insulin resistance, exercise or no exercise.
  30. D

    Why does glucose have a lower rf value than fructose?

    Even though their molecular formulas are the same? Fructose is an isomer of glucose and they are both cyclic and have 5 carbons so I was wondering why fructose was higher on the TLC plate than glucose. Thank you.
  31. D

    Finding mass of glucose in standard solutions

    Homework Statement This is for an experiment that separates sugars in a sample using TLC. We are given a glucose standard solution with a concentration of 1mg/ml as well as 3 standard sugar solutions (glucose, fructose and maltose) all with the same concentration (10mg/ml) in 10% v/v...
  32. R

    Exploring Semi-Porous Transparent Membranes for Glucose Transport

    Hi! My friends and I have been working on a project which encapsulates the use of semi porous transparent membranes that can selectively pass glucose molecules through them in one direction. Does such a membrane already exist? Where can I get literature on the construction and/or existence of...
  33. M

    Why is glucose stored as glycogen in the liver and muscle?

    Homework Statement Why does the human body spend two high energy phosphate bonds to store glucose as glycogen in muscle and liver, and not just as glucose? What is the advantage in using energy to polymerize the glucose molecule? Homework Equations The Attempt at a Solution...
  34. S

    Why are all the OH opposite to each other in D and L glucose?

    I thought D and L referred to the direction of the OH on the LAST chirality center. So why are all the other OH also switched up? http://upload.wikimedia.org/wikipedia/commons/thumb/0/06/DL-Glucose.svg/300px-DL-Glucose.svg.png
  35. V

    How do I do this glucose dilution problem?

    Homework Statement how do you prepare a solution for 25ml of 2.5% glucose form a stock of 1.75M glucose i don't get how you would do this without the density of 2.5% glucose solution Homework Equations c1v2 = c2v2 molecular mass glucose = 180g/molThe Attempt at a Solution not sure if I am...
  36. C

    Glucose + Water: Output, Storage & Taste

    Sir/Madam, what is out put of glucose+water?is it possion? can i store this in packets? how long? if i combine "water+glucose+citric acid+carbon dioxide" what's the output? which taste i get?
  37. C

    Synthesis of Glucose or Other High-Energy Sugars

    Is there a way to synthesize glucose, or any other high energy sugars, from simpler compounds? What are the compounds and how can they be converted into glucose? Can you describe the reactions that take place to form glucose? This is what I mean, as an example: Say we have methane, or CH4...
  38. N

    Chemistry Question on metabolism of glucose

    Homework Statement The metabolism of glucose, C6H12O6, yields Co2(g) and H2O(l) as products. Heat released in the process is converted to useful work with about 70% efficiency. Calculate the mass of glucose metabolized by a 59.0-kg person in climbing a mountain with an elevation gain of...
  39. C

    What are the functional groups of glucose?

    Homework Statement What is your favorite food? Name one organic molecule that is present that food. In the space provided, describe the major structural features of this molecule, including any important functional groups.Homework Equations ~The Attempt at a Solution I've decided to pick...
  40. D

    Calculating the Molecular Weight of Glucose Polymers

    Glucose (C6H12O6) is a monomer that can form naturally occurring polymers. What would be the approximate molecular weight of a polymer made from 5 glucose monomers? a) 810 b) 828 c) 882 d) 900 i said D, but my friend in convincing me its B :S
  41. A

    How does fat change to glucose?

    How does fat change to glucose? Please give links, slideshows and e-books, where are reactions, schemes, mechanisms and other useful information. Thank you!
  42. A

    Does Drinking More Water Help Lower Blood Glucose Levels?

    i've been questioning that water helps to lower glucose level in blood, if maybe 40grams of glucose is maximum per day and it need 3 liter of water.. but what if i ate 80grams of glucose and 6 liter of water to dilute it, will it work?? where does the extra glucose go?
  43. X

    Thermodynamics of Reactions with Glucose

    Homework Statement Homework Equations ΔH rxn = ΔH products - ΔH reactants ΔU = q + w The Attempt at a Solution Pretty overwhelmed with the entire problem. Since the ΔH's of all reactants and products were in the literature for the reference temperature of 298.15 K, I was able to...
  44. B

    Glucose effectiveness and insulin sensitivity

    I'm reading an article about glucose dynamics and there were two terms I wasn't sure about. I'm guessing insulin sensitivity is how much glucose is absorbed by a certain amount of insulin, but what is glucose effectiveness? Any help is appreciated.
  45. U

    Alpha & Beta Glucose: How to Differentiate

    Hi all, I find difficulties in recognizing between alpha and beta Glucose. Can anybody explain briefly how can I differentiate between them ?
  46. I

    Chemical equation for glucose osazone and limiting reactants

    Homework Statement Okay, a while ago, I did a lab that had me get glucose osazone (C18-H22-N4-O4). Now, I am trying to calculate the theoretical mass of the osazone. The chemical equations goes as follows: C6-H5-N2-H3*HCl + Na-C2-H3-O2*H2-O ------> C6-H5-N2-H3 + H-C2-H3-O2 + Na-Cl +...
  47. B

    Life prefers to use glucose over other sugars

    We learned that life prefers to use glucose over other sugars (catabolite repression). 1) Why is glucose preferred? 2) Why do sperm use fructose instead of glucose?
  48. X

    Rate of Glucose uptake by yeast cells

    You are required to plan an investigation to find out the rate of glucose uptake by yeast cells varies with glucose concentration material resources - 10% glucose solution - disilled water -yeast suspension - Benedicts reagent I have done the introduction, apparatus required, but I am...
  49. J

    Tracing the path of hydrogen atoms after the ingestion of glucose.

    After ingestion of glucose, trace the path of the hydrogen atoms in glucose beginning within the digestive tract and ending with the oxidation of the glucose during aerobic respiration. Can anyone help me out with this problem? Thanks to everyone in advance!