Textbook Notes (368,192)
Canada (161,707)
Biology (653)
BIO152H5 (140)
Chapter 5

Chapter 5 Textbook Notes - An Introduction to Carbohydrates

3 Pages
Unlock Document

Fiona Rawle

Notes From Reading CHAPTER 5: A N INTRODUCTION TO CARBOHYDRATES PGS .85-98) Key Concepts - Sugars and other carbohydrates are highly variable in structure - Monosaccharides are monomers that polymerize to form polymers called polysaccharides, via different types of glycosidic linkages. - Carbohydrates perform a wide variety of functions in cells, ranging from energy storage to formation of tough structural fibers. 5.1 Sugars as Monomers Monosaccharides Vary in Structure (1) Location of the carbonyl group. o Aldose: The carbonyl is at the end of the monosaccharide. o Ketose: The carbonyl is in the middle of the sugar’s carbon chain. (2) Number of carbon atoms present. o Triose: three o Pentose: five o Hexose: six (3) Spatial arrangement of their atoms. o Different arrangement of the hydroxyl groups. 5.2 The Structure of Polysaccharides - Polysaccharides are polymers that form from monosaccharides through a condensation reaction between two hydroxyl groups to create a glycosidic linkage. (1) The monomers joined by glycosidic linkages can be identical or different. (2) The glycosidic linkages can form between any two hydroxyl groups; so the location and geometry of these bonds vary widely. 5.3 What Do Carbohydrates Do? - Carbohydrates are important building blocks in the synthesis of other molecules. - They indicate cell identity. - They store chemical energy. - They provide cells with fibrous structural materials. Glycoproteins: Cell Identity - Although polysaccharides are unable to store information, they do display information on the outer surface of cells in the form of glycoproteins—proteins joined to carbohydrates by covalent bonds. - Glycoproteins are key molecules in cell-cell recognition and cell-cell signaling. Starch and Glycogen: Storage Polysaccharides Notes From Reading CHAPTER 5: A N INTRODUCTION TO CARBOHYDRATES (PGS.85-98) - Plants store sugars as starch, which is made of many α-glucose monomers joined by α-1,4- glycosidic linkages. This causes the monomer chain to form a helix. Animals store sugars as glycogen. - - Starch can be branched (amylose) or unbranched (amylopectin). Glycogen is highly branched. - Branching occurs when glycosidic linkages form between carbon 1 of a glucose monomer on one strand and carbon 6 of a glucose monomer on another strand. Carbohydrates and Free Energy - In chemical evolution, the kinetic energy of sunlight and heat were converted into chemical energy stored in the bonds of H CO 2nd HCN. - Today, most sugars are produced via photosynthesis [CO + H O +
More Less

Related notes for BIO152H5

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.