6.4 The Building Blocks of Life All living things are compose of organic molecules The six most common elements found in organic molecules include: C, H, N, O, P, S.

C Carbon H Hydrogen N Nitrogen O Oxygen P Phosphorus S Sulfur

The element carbon is a component of almost all biological molecules. Chapter 6 Chemistry in Biology 6.4 The Building Blocks of Life Organic Chemistry The element carbon is a component of almost all biological molecules.

Carbon atoms can be joined to form carbon molecules. Chapter 6 Chemistry in Biology 6.4 The Building Blocks of Life Macromolecules Carbon atoms can be joined to form carbon molecules.

Monomers: the smallest, repeating molecular unit (identical or nearly identical in composition) that makes up a larger molecule Polymers: long molecules made up of monomers

Organic Polymer

Organic Polymer

Organic polymers are also called macromolecules Macromolecules are large molecules formed by joining smaller organic molecules together.

There are four major macromolecules associated with biology: Carbohydrates Lipids Proteins Nucleic acids

Chapter 6 Chemistry in Biology

General formula: (CH2O)n Chapter 6 Chemistry in Biology 6.4 The Building Blocks of Life Carbohydrates Compounds composed of carbon, hydrogen, and oxygen in a ratio of 1C: 2H: 1O General formula: (CH2O)n

Chapter 6 Chemistry in Biology 6.4 The Building Blocks of Life If n is between three and seven the compound is called a simple sugar or monosaccharide. Ex. C6H12O6

Glucose is one very important monosaccharide used by cells for energy It is found in the human bloodstream

Two monosaccharides joined together form a disaccharide.

Sucrose and lactose are two examples of disaccharides. Sucrose is table sugar Lactose is milk sugar

How are disaccharides formed? Dehydration synthesis: formation of disaccharide by removing water from the monosaccharides

Longer carbohydrate molecules are called polysaccharides.

Glycogen is an example of a polysaccharide. Animals store it in the liver It is a short term energy storage molecule

How do organisms get energy from these????? The bonds between them are broken, releasing energy The bonds store energy!

Hydrolysis: adding water to split a disaccharide or polysaccharide and release energy

Functions of Carbohydrates: Primary source of energy for organisms

Structural support in plants (cellulose) Main component in shells (chitin)

Carbohydrates Are: Manufactured by green plants only: Occurs during photosynthesis 6 CO2 + 6 H2O → C6H12O6 + 6 O2

Lipids Molecules made mostly of carbon and hydrogen Make Up: Fats Oils Chapter 6 Chemistry in Biology 6.4 The Building Blocks of Life Lipids Molecules made mostly of carbon and hydrogen Make Up: Fats Oils Waxes

Functions of Lipids Primary function is to store energy Make up cell structures Form chemical messages between cells Protection (wax on plant leaves)

Lipid Structure: Fatty acid tail

Fatty acid tail is a chain of carbon atoms bonded to hydrogen atoms and other carbon atoms by single or double bonds The bonds determine if the lipid is classified as saturated, unsaturated or polyunsaturated

Basic Structure of Lipids

Chapter 6 Chemistry in Biology 6.4 The Building Blocks of Life Saturated fats have tail chains with only single bonds between the carbon atoms.

Unsaturated fats: lipids that have at least one double bond between carbon atoms in the tail chain

Fats with more than one double bond in the tail are called polyunsaturated fats.

Important Biological Lipids: Phospholipids: create the structure and function of the cell membrane

Hydrophilic head: dissolves in water Hydrophobic tail: does not dissolve in water Why is this important?

Lipids Also, responsible for the formation of important steroids including hormones and cholesterol

Protein A compound made of small carbon compounds called amino acids Chapter 6 Chemistry in Biology 6.4 The Building Blocks of Life Protein A compound made of small carbon compounds called amino acids Amino acids are small compounds that are made of carbon, nitrogen, oxygen, hydrogen, and sometimes sulfur.

Amino acids have a central carbon atom. Chapter 6 Chemistry in Biology 6.4 The Building Blocks of Life Amino acids have a central carbon atom. One of the four carbon bonds is with hydrogen. The other three bonds are with an amino group (–NH2), a carboxyl group (–COOH), and a variable group (–R).

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Amino acids are bonded together in a chain by peptide bonds Proteins are also called polypeptides

Protein Functions: Make up mass Involved in almost all functions Structure Chemical signals between cells Control cell growth and repair Enzymes (biological catalysts)

Enzymes Enzymes: biological catalysts Made of proteins

Chapter 6 Chemistry in Biology 6.2 Chemical Reactions Enzymes Catalyst is a substance that lowers the activation energy needed to start a chemical reaction.

Activation energy: the minimum amount of energy needed for reactants to form products in a chemical reaction.

This reaction is exothermic and released heat energy. Chapter 6 Chemistry in Biology 6.2 Chemical Reactions This reaction is exothermic and released heat energy. The energy of the product is lower than the energy of the reactants.

This reaction is endothermic and absorbed heat energy. Chapter 6 Chemistry in Biology 6.2 Chemical Reactions This reaction is endothermic and absorbed heat energy. The energy of the products is higher than the energy of the reactants.

It does not increase how much product is made. It does not get used up in the reaction.

How do enzymes work?

Substrates: Reactants that bind to the enzyme Chapter 6 Chemistry in Biology 6.2 Chemical Reactions Substrates: Reactants that bind to the enzyme Active site: Specific location where a substrate binds on an enzyme

Chapter 6 Chemistry in Biology 6.2 Chemical Reactions The active site changes shape and forms the enzyme-substrate complex, which helps chemical bonds in the reactants to be broken and new bonds to form. Factors such as pH, temperature, and other substances affect enzyme activity.

Chapter 6 Chemistry in Biology

Nucleic Acids: Made up of smaller subunits called nucleotides Nucleotides consist of carbon, nitrogen, oxygen, phosphorus, and hydrogen atoms

Nucleic Acid Functions: Store and transmit genetic information Two types of nucleic acids: DNA RNA

12.1 DNA: The Genetic Material Chapter 12 Molecular Genetics 12.1 DNA: The Genetic Material DNA Structure Nucleotides Consist of a five-carbon sugar, a phosphate group, and a nitrogenous base