1. Online Counseling Resource YCMOU ELearning Drive… School of Architecture, Science and Technology Yashwantrao Chavan Maharashtra Open University, Nashik – 422222, India

2. SEP-SBI072-CP1-02 Introduction Programmes and Courses SEP –SBI072- CP1- UN01

3. School of Science and Technology, Online Counseling Resource… Credits  Academic Inputs by Sonali Alkari Faculty YCMOU Nagpur Centre, Faculty LAD college P.G. D of Biotechnology Research officer Ankur Seeds Pvt Ltd sonalisa_alkari@yahoo.co.in Sonalisaal@rediffmail.com 3© 2008, YCMOU. All Rights Reserved.

4. School of Science and Technology, Online Counseling Resource… © 2008, YCMOU. All Rights Reserved.4 How to Use This Resource  Counselor at each study center should use this presentation to deliver lecture of 40-60 minutes during Face-To-Face counseling.  Discussion about students difficulties or tutorial with assignments should follow the lecture for about 40-60 minutes.  Handouts (with 6 slides on each A4 size page) of this presentation should be provided to each student.  Each student should discuss on the discussion forum all the terms which could not be understood. This will improve his writing skills and enhance knowledge level about topics, which shall be immensely useful for end exam.  Appear several times, for all the Self-Tests, available for this course.  Student can use handouts for last minutes preparation just before end exam.

5. School of Science and Technology, Online Counseling Resource… © 2008, YCMOU. All Rights Reserved.5 Learning Objectives  After studying this module, you should be able to: Discuss Monosaccharides Describe different types of monosaccharides. State properties of monosaccharides.

6. School of Science and Technology, Online Counseling Resource… Monosaccharides-1  The smallest carbohydrates are called monosaccharides (mono means “one”; saccharide means “sugar”).  As the name implies, these are single sugar molecules.  The most common monosaccharides, such as fructose and glucose, have six carbon atoms, but monosaccharides can have as few as three or as many as seven.  Monosaccharides with five or more carbons usually have a ring-shaped structure when they are in a solution. © 2008, YCMOU. All Rights Reserved.6

7. School of Science and Technology, Online Counseling Resource… Monosaccharides-2  Monosaccharides are colorless, crystalline solids that are freely soluble in water but insoluble in non polar solvents.  Most have a sweet taste.  The backbones of common monosaccharide molecules are unbranched carbon chains in which all the carbon atoms are linked by single bonds.  In the open-chain form, one of the carbonatoms is double-bonded to an oxygen atom to form a carbonyl group; each of the other carbon atoms has a hydroxyl group. © 2008, YCMOU. All Rights Reserved.7

8. School of Science and Technology, Online Counseling Resource… Monosaccharides-3  Monosaccharides, the simplest carbohydrates, are aldehydes or ketones that have two or more hydroxyl groups;  The empirical formula of many is (C-H2O)n, literally a "carbon hydrate."  Monosaccharides are important fuel molecules as well as building blocks for nucleic acids.  The smallest monosaccharides, for which n = 3, are dihydroxyacetone and d andl-glyceraldehyde.They are referred to as trioses.  Simple monosaccharides with four, five, six, and seven carbon atoms are called tetroses, pentoses, hexoses, and, respectively. © 2008, YCMOU. All Rights Reserved.8

9. School of Science and Technology, Online Counseling Resource… Monosaccharides-4  The simplest of the carbohydrates, the monosaccharides,are either aldehydes or ketones with two or more hydroxyl groups; the six-carbon monosaccharides glucose and fructose have five hydroxyl groups.  Many of the carbon atoms to which hydroxyl groups are attached are chiral centers, which give rise to the many sugar stereoisomers found in nature. © 2008, YCMOU. All Rights Reserved.9

10. School of Science and Technology, Online Counseling Resource… Monosaccharides: Aldoses and Ketoses  If the carbonyl group is at an end of the carbon chain (that is, in an aldehyde group) the monosaccharideis an aldose;  If the carbonyl group is at any other position (in a ketone group) the monosaccharide is a ketose.  The simplest monosaccharides are the two three-carbon trioses: glyceraldehyde, an aldotriose, and dihydroxyacetone, a ketotriose.  Monosaccharides with four, five, six, and seven carbon atoms in their backbones are called, respectively, tetroses, pentoses, hexoses, and heptoses. © 2008, YCMOU. All Rights Reserved.10

11. School of Science and Technology, Online Counseling Resource… d-Aldoses containing 3,4,5 & 6 Carbon Atoms © 2008, YCMOU. All Rights Reserved.11

12. School of Science and Technology, Online Counseling Resource… d–Ketoses containing 3,4,5 & 6 Carbon Atoms © 2008, YCMOU. All Rights Reserved.12

13. School of Science and Technology, Online Counseling Resource… Monosaccharides Have Asymmetric Centers  All the monosaccharides except dihydroxyacetone contain one or more asymmetric (chiral) carbon atoms and thus occur in optically active isomeric forms.  The simplest aldose, glyceraldehyde, contains one chiral center (the middle carbon atom) and therefore has two different optical isomers, or enantiomers © 2008, YCMOU. All Rights Reserved.13

14. School of Science and Technology, Online Counseling Resource… Glycosidic Bond-1  Monosaccharides can be modified by reaction with alcohols and amines to form adducts. For example, d-glucose will react with methanol in an acid- catalyzed process: the anomeric carbon atom reacts with the hydroxyl group of methanol to form two products, methyl a -d-glucopyranoside and methyl b -d-glucopyranoside.  These two glucopyranosides differ in the configuration at the anomeric carbon atom. The new bond formed between the anomeric carbon atom of glucose and the hydroxyl oxygen atom of methanol is called a glycosidic bond specifically, an O-glycosidic bond. © 2008, YCMOU. All Rights Reserved.14

15. School of Science and Technology, Online Counseling Resource… Glycosidic Bond-2 © 2008, YCMOU. All Rights Reserved.15

16. School of Science and Technology, Online Counseling Resource… Reducing and Reducing Sugar  Glycosides such as methyl glucopyranoside do not react, because they are not readily interconverted with a form that includes a free aldehyde group.  Solutions of cupric ion (known as Fehling's solution) provide a simple test for sugars such as glucose.  Sugars that react are called reducing sugars; those that do not are called nonreducing sugars. © 2008, YCMOU. All Rights Reserved.16

17. School of Science and Technology, Online Counseling Resource… Monosaccharides Are Reducing Agents  Monosaccharides can be oxidized by relatively mild oxidizing agents such as ferric (Fe3) or cupric (Cu2) ion.  The carbonyl carbon isoxidized to a carboxyl group. Glucose and other sugars capable of reducing ferric or cupric ion are called reducing sugars.  This property is the basis of Fehling’s reaction, a qualitative test for the presence of reducing sugar.  By measuring the amount of oxidizing agent reduced by a solution of a sugar, it is also possible to estimate the concentration of that sugar. © 2008, YCMOU. All Rights Reserved.17

18. School of Science and Technology, Online Counseling Resource… What You Learn…  You have learnt : Monosaccharides are aldehydes or ketones that have two or more hydroxyl groups. Monosaccharides are important fuel molecules as well as building blocks for nucleic acids. All the monosaccharides except dihydroxyacetone contain one or more asymmetric (chiral) carbon atoms and thus occur in optically active isomeric forms. Monosaccharides are reducing sugars. 18© 2008, YCMOU. All Rights Reserved.

19. School of Science and Technology, Online Counseling Resource… Critical Thinking Questions 1.What are monosaccharides? 2. Why monosaccharides are reducing sugars. © 2008, YCMOU. All Rights Reserved.19

20. School of Science and Technology, Online Counseling Resource… Hints For Critical Thinking Question 1.aldehydes or ketones that have two or more hydroxyl groups, chemical composition and structural details, and importance. 2.Free carbon atom © 2008, YCMOU. All Rights Reserved.20

21. School of Science and Technology, Online Counseling Resource… Study Tips:1  Book1 Title: Molecular Cell Biology Author: Harvey Lodish, David Baltimore Publisher:Publishers: W. H. Freeman and Company  Book2 Title: Principles of Biochemistry Author: AlbertL Lehninger Publisher:CBS Publishers & Distributors

22. School of Science and Technology, Online Counseling Resource… Study Tips:2  Book3 Title: Biochemistry Author: Lubert stryer Publishers: Freeman International  Book4 Title: Biochemistry Author: Keshav Trehan Publishers: Wiley Eastern

23. School of Science and Technology, Online Counseling Resource… Study Tips www.en.wikipedia.org Microsoft Encarta Encyclopedia http://en.wikipedia.org/wiki/ Wikipedia the free encyclopedia

24. School of Science and Technology, Online Counseling Resource… End of the Presentation Thank You! 24© 2008, YCMOU. All Rights Reserved.