Biology 111 - Chapter 5

Carbohydrate

Sugars

Monomer

Monosaccharides

Oligosaccharides

Few sugars

Polysaccharides

Many sugars

Carbohydrate formula

(CH2O)n

Purpose of Glucose

Important for cellular respiration and making ATP

Four ways carbohydrates differ

• Hydroxyl

• Carbonyl

• Number of Carbons

• Linear and Ring Formations

Two configurations of carbonyl group

• Aldose (carbonyl group at the end of the carbon chain)

• Ketose (carbonyl group in the middle of the carbon chain)

Cell are in aqueous environment

Cell are in aqueous environment

Polysaccharides(long chains of monosaccharides) are formed by polymerization. During this process, monosaccharides are linked together by glycosidic linkages.

Polysaccharides(long chains of monosaccharides) are formed by polymerization. During this process, monosaccharides are linked together by glycosidic linkages.

Purpose of Starch

Energy storage in plant cells

Purpose of gyclogen

Animal storage of sugar

Cellulose

Structural polymer found in plants

Chitin

Structural polymer for crustaceans, insects, and other arthropods

Purpose of peptidoglycan

Structure in bacterial cell walls

What is not a polymer?

Glucose

Purpose of cellular respiration

When a cell needs energy, it breaks down glucose to make ATP.

Types of monosaccharides

• Glucose

• Galactose

• Fructose

Carbohydrates relation towards water

Polar and hydrophilic

Triose

3 Carbons

Pentose

5 Carbons (important for DNA + RNA)

Hexose

6 Carbons

Glycosidic linkage

Similar to a peptide bond in proteins

Types of Polysaccharides

• Starch

• Glycogen

• Cellulose

• Chitin

• Peptidoglycan

Starch 

Energy storage in plant cells

• Function: store energy

Glucose polymer components: 

• Alpha glucose monomers

• Forms a helix

• Amylose

  • Alpha 1,4

  • No branching

• Amylopectin

  • Alpha 1,6

  • Branches once in every 30 monomers

Glycogen

• Stored in liver and muscle

• Can be broken into glucose monomers for energy

• Glucose polymer components:

  • Highly branched alpha glucose polymer, nearly identical to starch

  • Branches once in about 1 out 10 monomers

Cellulose

• Major component of cell wall

• Function: structure & support

• Glucose polymer components:

  • Beta 1,4 linkage, linear molecule

Insoluble fiber

Cellulose on food packages

Beta 1,4 Glycosidic linkage

Organized into fibers and sheets, provides strength and elasticity

Glycoproteins

Proteins with attached carbohydrates

Glycolipids

Lipids with attached carbohydrates

Function of Carbohydrates

• Serve as precursors to other molecules such as nucleotides or amino acids

• Provide fibrous structural material 

• Indicate cell identity

• Store chemical energy

Monosaccharides differ from one another in whether they contain a ketose or an aldose group

Monosaccharides differ from one another in whether they contain a ketose or an aldose group

Soil pH affecting plant height

Soil pH is independent, plant height is dependent