Macromolecules A Little More on Carbon, Carbohydrates & Lipids

Organic and Inorganic compounds  Organic compounds- consist of Carbon, Hydrogen and sometimes Oxygen  Inorganic compounds- do not contain Carbon (exception CO 2 )

The uniqueness of carbon comes from the fact that it can bond to itself. Carbon atoms can form long straight chains:

Or as branched chains: Or as rings:

A carbon-carbon single bond A carbon-carbon double bond A carbon-carbon triple bond Neighboring carbon atoms can form double and triple bonds in addition to single carbon-carbon bonds Each carbon atom forms 4 bonds. As you increase the number of bonds between carbon atoms, the number of hydrogen atoms in the molecule decreases

What are carbohydrates? Sugars and starches Used for: Energy storage Structural materials Made of C, H, O in a 1:2:1 ratio (CH 2 O) x 3 types Monosaccharides Disaccharides Polysaccharides

Question 1  Give 2 examples of carbohydrates 1.2.

Simple sugars – one _________? Function – major source of quick energy Examples: glucose, fructose, and galactose Monosaccharides

main source of energy Formula: C 6 H 12 O 6 Sources: ripe fruits, nectar, sap, blood Glucose vs. Fructose vs. Galactose Formula: C 6 H 12 O 6 Sources: Fruits Formula: C 6 H 12 O 6 Sources: Milk

Question 2 What do you notice about the chemical formulas for glucose, fructose and galactose?   All C 6 H 12 O 6 – they are isomers Question 3 What about their names??? They all end in ose

Isomer  Let’s make a definition for isomer…… Ideas?

Disaccharides 2 monosaccharides joined by covalent bond How does this happen? D ehydration synthesis (aka) Condensation reaction – water molecule released when bond is formed between two monomers Animation Example?

How are sugars broken down? Hydrolysis reaction – Opposite of dehydration reaction: water added to break apart bonds between 2 or more monomers

Examples: 1. Maltose (used in brewing beer) glucose +  maltose + H2OH2O 2. Sucrose (table sugar) glucose + fructose  sucrose +H 2 O 3. Lactose (sugar in milk) glucose + galactose  lactose + H2OH2O

Polysaccharides Polymer – large chains of monosaccharides Examples: 1. Starch – storage polymer in plants 2. Glycogen – storage polymer in animals 3. Cellulose – part of cell wall in plants 4. Chitin – used by insects, crustaceans, fungi Glycogen stores in liver cells

Exit Carbohydrates On a separate sheet of paper write down: 1. 3 things you learned about carbohydrates 1. 1 thing that is confusing to you

Please answer the following 1. What are the elements in carbohydrates and lipids? 2.What types of carbohydrates are there? 3. Give an example of a polysaccharide and what is it used for? 4. What are two types of lipids?

LIPIDS! Used for energy storage, protective structures Non-polar (NOT water soluble) Higher ratio of C to H than carbs (Ex: C 57 H 110 O 6 )

Copyright Pearson Prentice Hall The common categories of lipids are: Fats (triglycerides) - saturated or unsaturated Oils- liquid fat Waxes- protective/waterproof covering Steroids- Example: cholesterol and hormones

Common Lipids  Fats – triglycerides and phospholipids  Oils, butter  Steroids (sterols)- Steroids have a four carbon ring structure and a high hydrogen to carbon ratio.  Waxes-  Waxes- one long- chain fatty acid bonded to a long- chain alcohol group  ear wax  Leaf protective from water loss

Hydrophilic, “water- loving” head Hydrophobic, “water- fearing” tail C-H bonds nonpolar Fatty Acids Structure - Fatty Acids What makes the C-H bonds nonpolar?

Triglycerides ( most fat we consume is from triglycerides) 3 fatty acids 1 glycerol Used as energy storage. When you lose weight you want to lose triglycerides.

Question  1. What type of bonds are formed when Carbon is bonded to Hydrogen in the fatty acid chains? (Left side)  2. What type of bonds are formed when Carbon is attached to Carbon in the fatty acid chain? (right side)

2 Types of fatty acids Saturated ALL carbons bonded to 4 atoms Unsaturated Carbons NOT bonded to 4 atoms Single bonds Double bonds Straight chainKinks

Saturated – solid at room temperature Examples: lard, butter, fats in red meat Unsaturated – soft or liquid at room temperature Examples: fish fats, corn oil

Question Is this a saturated or unsaturated fat? Why?

Phospholipids Structural fat used to build cell membranes

EXIT QUESTION On the same paper you used for carbohydrates answer the following: 1. What is the major difference between saturated and unsaturated fatty acids? 2. Many people say fats are not good for you, so why not give them up? Explain.