CHAPTER 5 The Structure and Function of Macromolecules “You are what you eat!”

Standards Distinguish among proteins, carbohydrates, lipids, and nucleic acids. Identify the major structural components and functions of the four major macromolecules Objectives

Shoulder Partners

Flip Books Take out your flip books for notes Turn to last page – it should be open for notes about definitions and reactions

Building Macromolecules Take out the pieces of macromolecules that you colored and cut out last class period You also need one sheet of construction paper

What is a MACROmolecule? A Large molecule with a complex structure A polymer built from monomers Macromolecule “little” molecule

Poly - mer Many Parts A long molecule made of monomers bonded together

Mono - mer One Part The “building blocks” of polymers A monomer is a sub-unit of a polymer.

Three of life’s organic macromolecules are polymers Carbohydrates, Proteins, Nucleic acids

EXAMPLES What do all these pictures have in common? They are large, complex structures that were all built by small “monomers” or building blocks called Legos.

Explain to your partner how these Lego structures are like Polymers Think – Pair – Share Explain to your partner how these Lego structures are like Polymers What do all these pictures have in common? They are large, complex structures that were all built by small “monomers” or building blocks called Legos.

condensation reactions called dehydration synthesis (removal of water) How are Polymers made? How do monomers bind to form polymers? condensation reactions called dehydration synthesis (removal of water)

How do polymers break down? Hydrolysis reaction Hydro – lysis Water is added to break the bonds that hold the polymer together. Water To Break

Hydrolysis

Think – Pair – Share Why would polymers need to be “broken down”?

Classes of Organic Macromolecules: Carbohydrates Lipids Proteins Nucleic Acids

CARBOHYDRATES

Carbo - hydrate Monomer Monosaccharide Carbon Water Monomer Monosaccharide (“mono” = one; “saccharide” = sugar) Polymers Disaccharides (di = two) Polysaccharides (poly = many)

Think – Pair – Share What are some functions of carbohydrates?

Functions of Carbohydrates in living things: Major fuel/energy source Energy storage Can be used as raw materials for other Macromolecules Structural/building material in plants

Structure of Monosaccharides Contain only C, H, O All have the molecular formula - (CH2O)n

In aqueous solutions many monosaccharides form rings:

Structure of Disaccharides Consists of two monosaccharides The monosaccharides are joined by a glycosidic linkage (bond)

Polar Bears What reaction forms the glycosidic linkage (bond) between the monosaccharides to become a disaccharide? Dehydration synthesis

2 Build a Carbohydrate Assemble a disaccharide sugar. The building block/monomers of carbohydrates are ____________. Place ________of these into a chain Use the triangle water to point to the bond site. Draw an arrow to show if water is being added or released during this reaction. Label as a dissaccharide simple sugars 2

Build a Carbohydrate H2O

Polysaccharides Structure: Polymers of a few hundred or a few thousand monosaccharides. Functions: energy storage molecules structural support

Examples of Carbs:

Starch - plant storage form for energy easily broken down into glucose units

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

Why is Cellulose so strong? Glucose monomers are flipped to expose equal Hydroxyl groups on either side of the chain When Cellulose chains are lined up next to each other, they Hydrogen Bond making a strong material that’s difficult to break!

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

Penguins What reaction breaks the glycosidic linkage (bond) between the glucose molecules in glycogen so the monomers can be used for fuel? Hydrolysis

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

Build a Carbohydrate Assemble the remaining carbohydrate monomers into a polysaccharide sugar. Place the remaining carbohydrate monomers into a chain. Use the triangle water to point to the bond site. Draw an arrow to show if water is being added or released during this reaction.

Standards Distinguish among proteins, carbohydrates, lipids, and nucleic acids. Identify the major structural components and functions of the four major macromolecules Objectives

PROTEINS

Proteins Monomer amino acids connected by peptide bonds Have a 3 dimensional globular shape

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

20 different amino acids The sequence of amino acids determine the shape of the protein

Our body can only synthesize 12 of the 20 amino acids. Did you know? Our body can only synthesize 12 of the 20 amino acids.

Think – Pair – Share Where do we get the other 8 amino acids?

Polymers = polypeptides Peptide bonds connect amino acids to form polypeptide chains

Examples of Protein Functions Immune System Antibodies (proteins) bind to foreign substances Transport Membrane transport proteins - move substances across cell membranes Hemoglobin carries oxygen, iron, and other substances through the body. Muscle Contractions Signaling - Hormones such as insulin regulate sugar levels in blood.

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

Four Levels of Protein Structure Primary structure Is the unique sequence of amino acids in a polypeptide Figure 5.20 – Amino acid subunits +H3N Amino end o Carboxyl end c Gly Pro Thr Glu Seu Lys Cys Leu Met Val Asp Ala Arg Ser lle Phe His Asn Tyr Trp Lle

Is the folding of the polypeptide one time Secondary structure Is the folding of the polypeptide one time Forms an a helix or a b pleated sheet O C α helix β pleated sheet Amino acid subunits N H R

Is the overall three-dimensional shape of a polypeptide Tertiary structure Is the overall three-dimensional shape of a polypeptide CH2 CH O H O C HO NH3+ -O S CH3 H3C Hydrophobic interactions and van der Waals interactions Polypeptide backbone Hydrogen bond Ionic bond Disulfide bridge

Quaternary structure Is the overall protein structure that results from the combination of two or more polypeptide subunits

Polar Bears Explain the four levels of protein structure to your penguin

Sickle Cell Disease

Sickle Cell Disease: A simple change in Primary Structure

Enzymes proteins that act as a catalyst

Penguins List at least 2 factors that effect protein structure

Environmental Factors That Effect Protein Shape pH Temperature Salinity Denatured protein is biologically inactive Can sometimes “renature” if primary structure is unchanged.

Assemble a 4-monomer polypeptide. Build a Protein Assemble a 4-monomer polypeptide. The building block/monomers of proteins are ____________. Place 4 of these into a chain Use the triangle water to point to the bond site. Draw an arrow to show if water is being added or released during this reaction. Label as a 4-monomer polypeptide Amino Acids

? Build a Protein Assemble the remaining monomers into a polypeptide. Use the triangle water to point to the bond site. Draw an arrow to show if water is being added or released during this reaction. Label as a ___-monomer polypeptide ?

Standards Distinguish among proteins, carbohydrates, lipids, and nucleic acids. Identify the major structural components and functions of the four major macromolecules Objectives

LIPIDS What are Lipids? Fats, phospholipids, steroids, waxes, pigments Hydrophobic (“hydro”=water; “phobic” = fearing) Consist mostly of hydrocarbons Do NOT consist of polymers

Monomers The building blocks of all lipids are called Fatty Acids

Functions of Lipids in living things: Energy storage Cell membrane structure Protecting against desiccation (drying out). Insulating against cold. Absorbing shocks. Regulating cell activities by hormone actions.

Structure of Common Fats - Triglycerides Consist of a single glycerol and usually three fatty acids Glycerol – an alcohol with three carbons Fatty Acid - Long Hydrocarbon chains with a Carboxyl group at one end.

Saturated and Unsaturated Fats (b) Unsaturated fat and fatty acid cis double bond causes bending Oleic acid Unsaturated fats : one or more double bonds between carbons in the fatty acids allows for “kinks” in the tails liquid at room temp most plant fats Saturated fats: No double bonds in fatty acid tails solid at room temp most animal fats (a) Saturated fat and fatty acid Stearic acid

Saturated fatty acid

Unsaturated fatty acid

Assemble a triglyceride. Build a Lipid Assemble a triglyceride. The building block/monomers of lipids are ____________. Use your notes to assemble w/ correct structure/components Use the triangle water to point to the bond site. Draw an arrow to show if water is being added or released during this reaction. Label as a triglyceride Fatty Acids

Phospholipids Structure: Glycerol + 2 fatty acids + phosphate group. Function: Main structural component of membranes, where they arrange in bilayers.

Phospholipids in Water

Draw a Phospholipid Next to your triglyceride, draw a phospholipid Label the parts/components Label the drawing as a phospholipid

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

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

Standards Distinguish among proteins, carbohydrates, lipids, and nucleic acids. Identify the major structural components and functions of the four major macromolecules Objectives

NUCLEIC ACIDS

Nucleic Acid Monomers = Nucleotides Nucleotide = 5 carbon sugar, phosphate, and nitrogenous base Deoxyribose in DNA Ribose in RNA

Two Types of Nucleic Acids Polymers DNA (Deoxyribonucleic acid) double stranded 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 of proteins coded for by DNA is made from the DNA template molecule

Function of Nucleic Acids : The stuff of Genes Nucleic acids store and transmit hereditary information Genes Are the units of inheritance Code for the sequence of amino acids(making polypeptides) Made of nucleic acids

Both polymers function together for protein synthesis

Building the Polymer Phosphate group of one nucleotide forms strong covalent bond with the #3 carbon of the sugar of the other nucleotide.

DNA: Double helix 2 polynucleotide chains wound into the double helix Base pairing between chains with H bonds A - T C - G

The building block/monomers of lipids are ____________. Building DNA The building block/monomers of lipids are ____________. Build 2 nucleotides Use your notes to assemble w/ correct structure/components Link the 2 nucleotides together The phosphate group of one nucleotide binds to the pentose sugar of the next Label as DNA nucleotides

Building DNA Use your notes to assemble w/ correct structure/components Use the triangle water to point to the bond site. Draw an arrow to show if water is being added or released during this reaction. Label as a triglyceride

Summary of the Organic Molecules: