9th Grade BYOD. Organic Molecules. Carbohydrates

Organic Molecules. Carbohydrates

Learning outcomes

Content: to be able to distinguish different types of carbs and their main functions

Language: to be able to use specific vocabulary in explaining molecules in your body; to get familiar with usage of comparative and superlative structures.

1 Individual work. Answer question after reading the text and researching pictures.

The macromolecules in three of the four classes of life’s organic compounds—carbohydrates, proteins, and nucleic acids, all except lipids—are chain-like molecules called polymers. A polymer is a long molecule consisting of many similar or identical building blocks linked by covalent bonds, much as a train consists of a chain of cars. The repeating units that serve as the building blocks of a polymer are smaller molecules called monomers. Some monomers also have other functions of their own.

Dehydration (making of the molecule) and Hydrolysis (breaking down) reactions

2 Individual work. Think free! Answer question:

How many molecules of water are needed to completely hydrolyse a polymer that is ten monomers long?

3 Team work. Discuss answers with your team

4 Individual work. Fill in the blanks by using given words:

disaccharides

storage

polysaccharides

monosaccharides

Carbohydrates include sugars and polymers of sugars. The simplest carbohydrates are the (A)_____________, or simple sugars; these are the monomers from which more complex carbohydrates are built. They generally have molecular formulas that are some multiple of the unit CH2O. (B)___________ are double sugars, consisting of two monosaccharides joined by a covalent bond. Carbohydrate macromolecules are polymers called (C)____________, composed of many sugar building blocks. Glucose, galactose, and fructose are common monosaccharides, whereas common disaccharides include lactose, maltose, and sucrose. Starch and glycogen, examples of polysaccharides, are the (D)____________ forms of glucose in plants and animals, respectively.

5 Individual work. Just Do It! Then discuss answers with your partner.

1. Write the formula for a monosaccharide that has three carbons.

2. A dehydration reaction joins two glucose molecules to form maltose. The formula for glucose is C6H12O6. What is the formula for maltose?

6 Individual work. Watch the video and answer question.

1. QUESTION: Why do foods like meat, cheese, and eggs have the lowest glycemic index?