Carbohydrates The sweetest macromolecules Take out that homework

Carbohydrates: The sweetest macromolecules Take out that homework, and then… 1. (Answer now) Make a list of anything you’ve eaten or drank today that you think contained carbohydrates. 2. Copy Now, answer later: 2. What is the ratio of carbon to hydrogen and oxygen in a carbohydrate? 3. In carbohydrates, many _____ bond together to form a _______.

Macromolecules • Macro = “big” • Macromolecules are the 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.

Simple Sugars: Monosaccharides • All carbohydrates are made up of 1 or more monosaccharides • The most common monosaccharides have the chemical formula C 6 H 1206 • 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. C 6 H 1206 isomers Fructose Galactose

What we’ve seen so far: • Monosaccharides have a ratio of 1: 2: 1 C: H: O. Most are C 6 H 12 O 6. • 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 Glucose SUCROSE water

Polysaccharides – “Many Sugars” • Through the same 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.

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

Polysaccharide Example: Glycogen • Glycogen is a polysaccharide animals use to store sugar and the energy it contains. It is highly branched so it can be broken down faster.

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

Notice the ringshaped Monosaccharide subunit!

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.

Read! • HW: Read section 3 -3 pp 55 -56 “carbohydrates” #1 p. 57