Macromolecules

Guiding Questions How does the structure of each biological molecule relate to its specific function? How do enzymes impact chemical reactions in an organism?

Acids, Bases, and pH Do you remember the pH scale? Have you ever felt an acid vs a base? pH scale is used to indicate the concentration of H+ ions in solution H2O breaks down to H+ and OH-

Acids, Bases, pH Solutions with high concentrations of H+ are called acidic, 0-6 on the pH scale Lemon juice, car battery, vinegar Solutions with less concentrations of H+ are called bases, basic, or alkaline 8-14 on the pH scale Bleach, ammonia, soap

Buffers Buffers are weak acids or bases that can react with strong acids or bases to prevent sharp, sudden changes in pH An important way of controlling pH and maintaining homeostasis.

Carbon Anything that is made of carbon bonded molecules is called “Organic” Carbon is special because it has 4 valence electrons and allows it to form strong covalent bonds with many other elements All living things are made of molecules that consist of carbon bonded to other elements Carbon can bond to itself easily and will therefore form long chains

More Carbon Carbon bonds an be single, double, or triple bonds Carbon has the ability to form millions of different large and complex structures No other element can even come close to matching this versatility

Macromolecules Just what are macromolecules… Do you think you can name any? The 4 macromolecules are: Carbohydrates, lipids, Nucleic acids, proteins

Monomers vs Polymers

Carbohydrates These are compounds made up of carbon, hydrogen and oxygen atoms Ration of 1:2:1 Carbohydrates supply energy for cell activity Some carbohydrates will be used for structure Carbohydrates are actually all sugars

Simple Carbohydrates Simple sugars are always known as monosaccharaides Think monomers! Found in many fruits, table sugar Glucose (we will look at in a few units) is highly important to cell function.

Complex Carbs Larger macromolecules known as polysaccharides Glycogen-animal starch When glucose is too low(cell function), Glycogen is broken down instead Glycogen helps muscle contraction Cellulose in plants give it that rigid structure. Also the major component in wood and paper

Lipids Made up of mostly carbon and hydrogen Not soluble in water Fats, oils, waxes Can be used to store energy Some are important biological membranes Steroids are an important lipid Can be saturated or unsaturated Have a sugar end and a fatty acid tail

Lipids

Saturated Lipids where the fatty acid tail contains only single bonds Called saturated because it contains the maximum number of hydrogen atoms

Unsaturated Lipids where the fatty acid tail contains a double bond and therefore a “kink” These fats are typically liquid at room temperature

Nucleic Acids Contain hydrogen, oxygen, carbon, and phosphorous Assembled from individual monomers known as nucleotides Store and transmit hereditary, or genetic, information. Can be ribonucleic RNA Can be deoxyribonucleic DNA

Protein Contain nitrogen, carbon, hydrogen, oxygen Polymers made up of amino acids-you will see those in unit 6 Proteins are functional molecules built from one or more polypeptides Some proteins control the rate of reactions and regulate cell processes Others form important cellular structures Others transport substances into or out of cells to help fight disease

Proteins and structure There are 20 amino acids in nature All these amino acids can bond to each other Proteins are the most diverse macromolecule Proteins form peptide bonds Special type of covalent bond

Chemical Reactions A Chemical Reaction is a process that changes, or transforms, one set of chemicals into another. Some chemical reactions occur fast, some slow Elements or compounds that entre into a chemical reaction are know as reactants Elements produced by a reaction are know as products Chemical equations involve changes in the chemical bonds that join atoms in compounds.

Energy Energy is released or absorbed when chemical bonds are formed or broken If energy is released, reactions occur on their own- Exothermic If energy is absorbed, the reaction will need a source of energy to start.- Endothermic

Activation Energy Chemical reactions that release energy do not always occur spontaneously If they did, your book would just catch on fire The energy needed to get a reaction started is called activation energy

Enzymes What roles do enzymes play? Cells often need help speeding up chemical reactions. Therefore the produce catalyst These are substances that speed up the rate of a chemical reaction Enzymes work by lowering a reactions activation energy

Substrates Substrates are the reactants of enzyme-catalyzed reactions

Activation Site Activation sites are the places on enzymes where substrates bind. This site is so precise to the substrate that active sites are called lock and key sites

Test time