Carbohydrates, Proteins, and Lipids

Ch. 5.2--> 5.4

Quick Review (write down your answers)

• What is the difference between an organic molecule and an inorganic molecule?

• Compare monomers and Polymers.

• What happens when you build a polymer? Break down a polymer?– Polymers:

• Build --> dehydration reaction --> water removed

• Breakdown --> hydrolysis -->water added

Objectives

1. Structure & function of sugars

2. Name and function of 3 polysaccharides

3. Characteristics of lipids

4. Structure and function of fats, proteins, & amino acids

Carbohydrates

• Organic compound• Made of C, H, O

• Always CH2O ratio

CarbohydratesMonosaccharides

• Monosaccharides:– One sugar unit

• i.e., glucose

– Main Source of Energy!

CarbohydratesDisaccharides

• Double sugar• What reaction do cells

use to construct this?• Dehydration reaction• Sucrose

– glucose + fructose

– table sugar, plant sap

CarbohydratesPolysaccharides

• Long chains of sugar units• Starch

– Where do we find starch?– Found in plant cells

• Can we break it down?• Let’s try with some

crackers…• Chew for 1 min, do NOT

swallow. Write down initial taste and write down tastee after 1 min

The Breakdown

• Amylase in saliva -->

• Hydrolyzed(add H2O) the starch --> released maltose --> sweet taste

• Remember, adding water breaks down polymers

CarbohydratesPolysaccharides (types)

• Glycogen:– Polysaccharide used by humans– Store and break down to glucose when need energy

• Cellulose:– Found in cell wall of plants

• Provides structure• We can’t digest it, call it “fiber”• GREAT for pooping!

Check with your neighbor

• Explain the difference between a monosaccharide and a disaccharide. Give an example of each

• Monosachharide = one sugar unit; – examples include: glucose, fructose, or

galactose

• Disaccharide = two sugar units– Example: sucrose

Lipids

Ch. 5.3

Hydrophilic vs. HydrophobicWhat do these terms mean?

• Hydrophilic:– Water loving

• Examples?• Cotton, tissue,

watercolor paper

• Hydrophobic:– Water-avoiding

• Examples?• Wax, vinyl, rubber

Lipids

• Water avoiding compounds

• Hydrophobic

• Fats:– Glycerol + 3 fatty acids– Saturated and unsaturated

Two Types of Lipids:Saturated vs. Unsaturated

1. Saturated fat:• Single bonds

• Solid at room temp

2. Unsaturated fat:• C is double bonded• Loose arrangement• Liquid at room temp

What type of fat is this?• Saturated or Unsaturated?• Unsaturated!• How do you know?• Online activity 5.3

Proteins 5.4

Structural proteins: mouse cells

Proteins

• Constructed of monomers called amino acids – Only 20 amino acids. That’s it!

• Specific shapes --> diff. jobs

• Many different functions. Any ideas?– Structure for hair, muscles, nails, tendons,

enzymes, defend against harmful microorganisms, chemical reactions in cells

Building a Protein

• Amino acids (AA) link together in a chain, or polypeptide

• What kind of reaction happens when a “chain” is built?

• Dehydration reaction --> loss of water

• Diff. Order of AA --> diff. Proteins– Many possible combinations– Some proteins are 100 AA’s in

length!

• Online activity 5.4

Did we obtain our objectives?

1. Describe basic structure & function of sugars

2. Name and function of 3 polysaccharides

3. Characteristics of lipids

4. Structure and function of fats

5. Structure & function of proteins & amino acid