BIOMOLECULES Ms. Bosse – Fall 2015

Biology is the study of the living world. Bio = life Biology

Major Molecules of Life ◦ Macromolecules – giant molecules found in living cells; made from thousands of smaller molecules.

Macromolecules are formed by a process known as polymerization, in which large compounds are built by joining smaller ones together. The smaller units are called monomers. Monomers join together to form polymers.

◦ Dehydration Synthesis is the process of removing a H2O molecule from two reactants (monomers) to create bonds thus forming a single, larger molecule (polymer).

◦ Hydrolysis is the process of adding a H2O to a reactant to break bonds forming two separate molecules.

Four categories of biomolecules: ◦ Carbohydrates ◦ Lipids ◦ Proteins ◦ Nucleic Acids

Biomolecules have 4 common characteristics: 1.All are carbon based….meaning they all contain carbon. 2.They are formed from just a few elements which join together to form small molecules which join together, or bond, to form large molecules.

Common Characteristics 3.Each kind of biomolecule is built from a single type of building block. EXAMPLES: Carbohydrate - monosaccharide Lipid - fatty acid Protein - amino acid Nucleic Acid - nucleotide

4. The last common characteristic of all biomolecules is that their form determines their function. That means that their shape determines how they will behave and how they will react with other molecules. Common Characteristics

Carbohydrates Living things use carbohydrates as their main source of energy Plants use carbohydrates for structural purposes Carbohydrates are sugars and starches

Carbohydrates ◦ They are composed of carbon, hydrogen and oxygen. ◦ The carbon forms a carbon ring.

◦ Single sugar molecules are called monosaccharide. These are the monomers. ◦ Monosaccharides include glucose, fructose and galactose.

NOTE: Glucose and fructose join to form sucrose in the above picture. Glucose and fructose are monomers. Once they join, a molecule of water is lost, and the polymer, sucrose is formed. glucosefructose sucrose

A monosaccharide – Mono -Mono = “one or single” saccharide -saccharide = “sugar”  building block of all carbohydrates  Main energy molecules of living things =

Large macromolecules formed from many monosaccharides are known as polysaccharides; they are made in a process called polymerization. Polysaccharides are the polymer. Poly = “many” saccharide = “sugar” macro = “very large”

Polysaccharides are many monosaccharides bonded together.

Carbohydrate ◦ Polysaccharides include: starches,cellulose and glycogen.

Starch Starch is a carbohydrate that is used in food storage of plants. Potatoes, pasta and rice are rich in starch. Starches are very valuable because they provide a quick form of energy for the body.

Glycogen ◦ Glycogen is used for food storage in animals. It is stored in the liver and muscles of animals.

Cellulose ◦ Cellulose is used for structural support in plants…..mainly the stems and leaves. It is found in the cell walls of plants.

Monosaccharide (ONE simple sugar)

Polysaccharide (Many simple sugars)

Lipids ◦ Lipids are composed of carbon, hydrogen and oxygen. However the carbon is arranged in a chain…not a ring or circle like the carbohydrate.

Lipids o Fats, oils and waxes o Do not dissolve in water (insoluble) o Long term storage of energy….not quick energy like carbohydrates

Lipids are formed from a glycerol molecule and several fatty acids

Lipids are found in: ◦ Cell membranes ◦ Vitamins ◦ Hormones

Examples; fats, phospholipids, steroids Lipids

◦ Saturated fats join carbon to carbon with a single bond. ◦ Unsaturated fats join at least one carbon atom to another carbon atom with a double bond Lipids

◦ FATS: ◦ Saturated: solid at room temp. (butter) ◦ Unsaturated: oils at room temp. (olive oil) ◦ PHOSPHOLIPIDS: ◦ found in the cell membrane ◦ STEROIDS: ◦ estrogen, testosterone, cholesterol (hormones) Lipids

Nucleic Acids ◦ Nucleic Acids are composed of carbon, hydrogen, oxygen, nitrogen and phosphorus. ◦ Nucleic acids involve genetic materials, like DNA and RNA. DNA is the blueprint of life because it contains the instructions on how to make proteins in the body.

Nucleic Acids ◦ Nucleic acids store and transmit genetic information ◦ The individual molecules in nucleic acids are called nucleotides and are made of a sugar, a phosphate group, and a nitrogenous base ◦ The two kinds of nucleic acids are DNA and RNA ◦ The order of the individual nucleotides in a DNA or RNA molecule determine the traits in an organism

PROTEINS ◦ Proteins are composed of carbon, hydrogen, oxygen and nitrogen. ◦ The building block of a protein is an amino acid.

PROTEINS ◦ Proteins are organic molecules that form muscles, transport oxygen (hemoglobin), and act as hormones and enzymes. Most importantly, proteins determine how our bodies look and function. ◦ Proteins are made of amino acids linked together by a peptide bond.

Proteins ◦ There are 20 different amino acids found on our planet ◦ Amino acids are the building blocks of proteins. ◦ Different combinations of amino acids form different proteins ◦ Each protein has a specific role or job in an organism

◦ Some proteins control the rate of reactions and regulate cell processes ◦ Some proteins are used to form bones and muscles ◦ Some proteins transport substances into or out of cells and fight disease

Just like any tool, a protein’s function is determined by its shape.

Chemical Reactions and Enzymes ◦ A chemical reaction is a process that changes one set of chemicals into another set of chemicals ◦ Reactant: the chemicals entering the reaction ◦ Product: the chemicals made from the reaction

Many chemical reactions require energy in order for them to occur; humans eat food in order to supply energy for these chemical reactions

Energy needed to start a chemical reaction is activation energy. A Catalyst is a substance that speeds up the rate of a chemical reaction.

Enzymes ◦ Enzymes are proteins that act as biological catalysts in chemical reactions that occur in cells ◦ Enzymes are tools; they are NOT part of the chemical reaction and are the same after the reaction as they were before the reaction

◦ Enzymes lower the activation energies, allowing the chemical reaction to occur without needing so much energy to get started ◦ The reactants of enzyme- catalyzed reactions are called substrates Enzymes

◦ Enzymes are very specific to a particular substrate; they will only “fit” that particular molecule ◦ Enzymes can be affected by pH and temperature

ENZYME EXAMPLE ◦ Lactase is the enzyme that breaks down lactose in the body. Lactose is a major type of sugar found in milk. ◦ Salivary amylase is the enzyme that breaks down food in your mouth before it enters your digestive tract. -ose = sugar -ase = enzyme

How enzymes get their name: ◦ Enzymes are usually named by using the name of the substrate with ---ase added. ◦ EX: lactase

ENZYMES ◦ Enzymes are NOT used up or changed in the reaction. ◦ The place where the enzyme attaches to the substrate is the active site.