The Structure and Function of Macromolecules Learning objective: I can explain how sugar molecules are rearranged to form other macromolecules. Essential question: What is the structure and function of carbohydrates and lipids? “You are what you eat!”

1. What does it mean to be a MACROmolecule? You must be a Large molecule You have a complex structure Macromolecule “little” molecule

I. Most macromolecules are polymers, built from monomers (Structure) What is a monomer? Mono= one -mer = part A monomer is a sub-unit of a polymer. What is a polymer? Poly = many A long molecule made of monomers bonded together

II. Classes of Organic Molecules: Carbohydrates Lipids Proteins Nucleic Acids

A. CARBOHYDRATES

What are Carbohydrates? (Structure) Made of sugars and their polymers Have Carbon (C), Hydrogen (H), and Oxygen (O) elements. Functions of Carbohydrates in living things: Major fuel/ energy source Can be used as raw materials for other Macromolecules Complex sugars = building material in plants Base unit (monomer) is a monosaccharide.

a. Monosaccharide structure: A simple sugar Glucose C6H12O6 (Corn Syrup) Fructose C6H12O6 (in fruits) Galactose C6H12O6 (in milk)

b. Disaccharide structure: two simple sugars linked together Sucrose C12H22O11 (table sugar: glu + fru) Lactose C12H22O11 (milk sugar: glu + gal) Maltose C12H22O11 (formed from digestion of starch: glu + glu)

c. Polysaccharide structure: a chain of simple sugars Starch: found in plants for energy reserves Glycogen: in humans’ livers and muscles for energy reserves Cellulose: found in plant cell walls for structural purposes Chitin: found in insects exoskeleton and fungus cell walls for structural purposes Functions: energy storage molecules or for structural support

Chitin is a polysaccharide used as a structural material in arthropod exoskeleton and fungal cell walls.

Cellulose is a fiber-like structural material made of glucose monomers used in plant cell walls

Glycogen is the animal short-term storage form of energy Glucose monomers

B. LIPIDS What are Lipids? = C, H, O (Carbon, hydrogen, oxygen) Fats with varying structure Hydrophobic = (“Hydro” = water; “phobic” = Fearing)

Functions (Used for…) Long-term storage of energy In cell membranes (cholesterol) Protects against drying out (plant waxiness) Insulation against cold Speeds nerve transmissions Absorbs shocks Regulates cell activities by hormone actions

4. Structure of Lipids Triglycerides = Glycerol + 3 fatty acid tails Can be SATURATED or UNSATURATED

(a) Saturated fat and fatty acid Saturated Fats Saturated fats: All Hydrogens filled in. No double bonds in fatty acid tails Most animal fats Solid at room temperature (a) Saturated fat and fatty acid Stearic acid

(b) Unsaturated fat and fatty acid Unsaturated Fats Unsaturated fats : Have one double bond between carbons in the fatty acids allows for “kinks” in the tails Most plant oils (olive oil) Liquid at room temperature Polyunsaturated: have many double bonds (b) Unsaturated fat and fatty acid cis double bond causes bending Oleic acid

Saturated Fat Unsaturated Fat

3. Phospholipids Structure: Glycerol + 2 fatty acids + phosphate group. Function: Creates cell membranes

Phospholipid

Phospholipids in Water

4. Waxes Function: Lipids that serve as coatings for plant parts and as animal coverings.

5. Steroids Structure: Four carbon rings with no fatty acid tails Functions: Component of animal cell membranes (Ex: Cholesterol) Modified to form sex hormones

Topic Today: Proteins and Nucleic Acids Learning Objective: I can explain how sugar molecules are rearranged to form other macromolecules. Essential Question: What is the structure and function of proteins and nucleic acids?

PROTEINS

Proteins are very complex Proteins are very complex! Their specific structure determines their function. HEMOGLOBIN: Transport of gases and iron in blood ACTIN: Filament involved in muscle contraction

C. Proteins (Structure) What are Proteins? Structure: Contain Carbon (C), Hydrogen(H), Oxygen (O), and Nitrogen (N) + “R” Group (amino group) Monomer (the bricks) = Amino acids connected by “peptide bonds” Polymer (the house)= Multiple amino acids => Peptides or PROTEINS!

Peptide bonds connect amino acids to form polypeptide chains One or more polypeptide chains make up a protein

Amino Acids Monomers of polypeptides Molecules with carboxyl and amino groups Differ in their properties due to differing side chains, called R groups

Examples of Protein Functions Immune System Binding of antibodies (proteins) to foreign substances Transport Membrane transport proteins that move substances across cell membranes Hemoglobin carries oxygen, iron, and other substances through the body in your blood. Muscle Contraction Certain muscle fibers work together to contract or extend. Signaling Hormones such as insulin regulate sugar levels in blood.

20 different amino acids exist The sequence of amino acids and the interactions of the different amino acids determine a proteins shape

NUCLEIC ACIDS

D. Nucleic Acids : The stuff of Genes (Structure) What are Nucleic Acids? Contain elements Carbon (C), Hydrogen (H), Oxygen (O), Nitrogen (N), and Phosphorus (P) Monomer (Bricks)= Nucleotides Polymer (House)= DNA or RNA strand

D. Nucleic Acids : Function Nucleic acids store and transmit hereditary information Located in the nucleus (DNA) and cytoplasm (RNA) Genes Are the units of inheritance Program the sequence of amino acids (monomers) which create genes Programs your physical characteristics (like hair or eye color)

Two Kinds of Nucleic Acids DNA (Deoxyribonucleic acid) double stranded Shaped like double helix (looks like a twisted ladder) can self replicate makes up genes which code for proteins is passed from one generation to another RNA (Ribonucleic acid) single stranded functions in actual synthesis (creation) of proteins coded for by DNA

DNA RNA

Summary of the Organic Molecules: