Quick Exercise 5: Carbohydrate Structure and Function

General Instructions

1. This is an individual activity.
2. Answer the questions below. 
3. Submit your answers in pdf/jpg formats only.
4. Follow the file naming format: Chem40_QE5_<Section>_<LastName,Initial of First Name>. Example: Chem40_QE5_MHD_DelaCruzJ

Problems

1. Draw the open chain and the two anomers of D-galactopyranose, and predict the most stable form. Explain your answer.
2. Draw the structure of lactose (β-D-galactopyranosyl-(1→4)-D-glucose) and indicate the type of glycosidic bond present. 
3. Thought question: To reduce calorie intake, some ingredients in recipes are substituted. For example, instead of using flour, sugar, butter, egg etc, banana is used as the binding agent in recipes like the banana oatmeal cookie. What specific component in banana enables it to bind ingredients? Relate this function to the structure of this component. 

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Bonus Material: The Banana Oatmeal Cookie Recipe (in case you're curious)

• Materials Needed: 1-2 bananas, dry oats
• Steps to make the cookie:
  1. Mash 1-2 ripe bananas (~130g) in a bowl. 
  2. Add 1 cup of dry oats.
  3. Mix them well together. (Optional: You may choose to add raisins or chocolate or whatever yummies you like at this point.)
  4. Portion and shape your mixture into 6 cookies. 
  5. Put them in an oven or oven toaster at ~200^oC for 15-20 min or until brown. 
  6. Cool them and enjoy!

Voila! 2-3 ingredient cookie! (~130g banana, 1 cup dry oats, 35.1 g dark chocolate; 94 Cal per cookie). Nomnomnomnom!