TASKS: 1. Classify the following organic compounds: Do Now 10.12 OBJECTIVES: 1. Define carbohydrate, identify different types, and describe the main role of carbohydrates in organisms. 2. Identify monosaccharides as the monomers carbohydrates are made of, and the ratio of C:H:O in monosaccharides. Describe and distinguish hydrolysis and dehydration synthesis reactions. TASKS: 1. Classify the following organic compounds: C3H6 CH3CH2COOH H2NCH2COOH COH2

Macromolecules Macro = “big” Macromolecules are the large organic molecules made by and found in organisms. There are 4 major categories: Carbohydrates Proteins Nucleic Acids Lipids Today’s lesson is all about carbohydrates.

Carbohydrates: The sweetest macromolecules Carbohydrates store energy in living things. Sugar is a good example Q: Why is broccoli good for you and candy bad if they both are sources of carbohydrates? A: The broccoli (and other fruits and vegetables) also have OTHER important nutrients

#1 Thing to Know Carbohydrates (aka sugars) main job is to STORE ENERGY

Simple Sugars: Monosaccharides All carbohydrates are made up of 1 or more monosaccharides “mono-” = “one” “-saccharide” = sugar Monosaccharides are the building blocks of all carbohydrates. The most common monosaccharides have the chemical formula C6H1206 Can you now see why they’re called “carbo” – “hydrates” ?

An Example Glucose is one of the most common compounds on Earth. Notice the basic structure of a ring with other “stuff” attached.

ISOMERS Even though two compounds have the same chemical formula (# of each type of atoms), they may be different compounds because of how the atoms bond to each other. C6H12O6 isomers Galactose Fructose

What we’ve seen so far: Monosaccharides have a ratio of 1:2:1 C:H:O. Most are C6H12O6. Even though they contain the same numbers of atoms, there are many different isomers possible. Almost all monosaccharides form 5 or 6 atom rings as their basic structure

Disaccharides – “Double Sugars” Fructose SUCROSE Glucose water

Polysaccharides – “Many Sugars” Through the same dehydration synthesis (aka condensation) reaction we saw, many monosaccharides can be bonded together to form a gigantic compound called a polysaccharide. They can be made of anywhere from 3 up to THOUSANDS of monomers.

Dehydration Synthesis (Condensation Reaction) When monomers combine – they form water M1 H M2 OH + OH H Your book doesn’t discuss the Condensation Rxn – but it could come up in conversation H2O

Hydrolysis When polymers breakdown water is needed to break the bonds M1 H M2 OH OH H H2O

Polysaccharide Example: Cellulose Cellulose is a long straight chain of glucose monomers. It accounts for about 50% of the mass of wood, because it is the biggest component of plant cell walls

It’s the polysaccharide we’ll be experimenting with next week!

Notice the ring-shaped Monosaccharide subunit!

This is the bond we’ll be breaking in the lab!!! Here’s a small part of the long chain… This is the bond we’ll be breaking in the lab!!!

CRITICAL INFORMATION Carbohydrates are macromolecules made up of one or more monosaccharides. Their major function in organisms is to store energy. Cellulose is a polysaccharide found in plant cell walls. It is a polysaccharide made of many monosaccharides joined together.

Other Important Polysaccharides Glycogen: A highly branched polysaccharide used to store glucose in animals and fungi.

Other Important Polysaccharides Starch: A somewhat branched polysaccharide used to store glucose in plants. Most common energy source in human diet.