Biochemistry final ppt

CARBOHYDRATES

Objectives1 •To understand the classification of carbohydrates

2 •To become familiar with steroisomerism

3 •To draw the structures of and to indicate the reactions of several hexoses

4 •To compare the structures and reactions of disaccharides and polysaccharides

Carbohydrates• All carbohydrates are

composed of carbon, hydrogen, and oxygen in a 1:2:1 empirical ratio.

• The general empirical formula for a carbohydrate is CH2O.

If a carbohydrate has 5 carbons atoms, what would be its empirical formula?

If a carbohydrate has 12 hydrogen atoms present, what would be its empirical formula?

• Most carbohydrates end with the suffix -ose

C5H10O5

C6H12O6

Functions of Carbohydrates

• Provide energy source: A fuel source when catabolized during cellular respiration. Energy is stored in the chemical bonds within the molecule and released during cellular respiration. Usually simple sugars.

• Provide energy storage: Plants store energy in a complex carbohydrate form called starch (amylose). Animals store energy in a complex carbohydrate in their muscle tissue and liver in the called glycogen.

• Structural Building Material: Plants build their cell walls of a complex carbohydrate material called cellulose. Animals such as arthropods build their exoskeletons of a complex carbohydrate called chitin. Chitin is also found in the cell walls of Fungi.

Classes of Carbohydrates

• There are three major classes of carbohydrates:

1. Monosaccharides (simple sugars) These are the monomers or building blocks for all other classes of carbohydrates. Examples: glucose, fructose, galactose, and ribose.

2. Disaccharides are produced by joining two simple sugars by dehydration synthesis forming a covalent bond between them. Examples: sucrose (table sugar), maltose, lactose

3. Polysaccharides (complex carbohydrates) are produced by joining many monosaccharides together by many dehydration synthesis reactions forming a polymer molecule. Examples: amylose, glycogen, cellulose, and chitin

CARBOHYDRATES

THERE ARE 2 TYPES OF CARBOHYDRATES

Simple Complex

Simple Sugars are carbohydrates made up of 1 or 2 monomers. They also taste sweet.

Complex Carbohydrates…What are they?

Complex Cabohydrates are polymers made up of many monomers.

Most also taste starchy.

Simple Sugars

Complex Carbohydrates

CarbohydratesCarbohydrates (or saccharides) consist of

only carbon, hydrogen and oxygenCarbohydrates come primarily from plants,

however animals can also biosynthesize them

The “Carbon Cycle” describes the processes by which carbon is recycled on our planet- Energy from the sun is stored in plants, which use photosynthesis to convert carbon dioxide and water to glucose and oxygen- In the reverse process, energy is produced when animals oxidize glucose during respiration

6CO2 + 6H2O + EnergyPhotosynthesis

RespirationC6H12O6 + 6O2

Simplified Carbon Cycle