The Chemistry Of Life Chapter 7

Atom- The smallest particle of matter

Element A substance made up of all of the same atoms. This cannot be broken down into a simpler substance.

Elements In Organisms 90 of the elements occur naturally. Symbol % in Human Body Oxygen O 65.0 Carbon C 18.5 Hydrogen H 9.5 Nitrogen N 3.3 Calcium Ca 1.5 Phosphorus P 1.0 Potassium K 0.4 Sulfur S 0.3 Sodium Na 0.2 Chlorine Cl Magnesium Mg 0.1 90 of the elements occur naturally. Less than 25 elements are essential to living organisms.

Trace Elements Some elements are necessary, but only in very tiny amounts. Trace elements help to maintain healthy cells. Some of the trace elements essential to life include: Iron, Iodine, Copper, Manganese, Cobalt, Boron, Zinc, Fluorine, Selenium and Chromium

Molecules & Compounds When two atoms chemically combine, or bond, they become a molecule, or a compound.

Water- An Important Molecule Water is a compound made up of 1 Oxygen and 2 Hydrogen atoms= H2O. Water makes up 70- 95% of organisms. Water dissolves materials so they can be transported. Water is a POLAR MOLECULE, which means that one end has a positive charge and the other end has a negative charge.

Chemical Reactions When chemical reactions occur, bonds between atoms are formed or broken and substances are changed into new substances. Chemical reactions involve energy. Chemical reactions are necessary to break down and build molecules organisms need to function. All the chemical reactions that happen in an organism constitute that organism’s METABOLISM.

Biochemistry- The Substances Of Life Organic Compounds: Compounds that contain Carbon (C) Organic substances are made by living things. For example: Organic materials- silk, cotton, wool

Role of Carbon Carbon has the ability to bond with many other elements. They can bond together as chains, branched chains or rings. There is an infinite variety of possible carbon structures- allowing for a great variety of organic substances.

Molecular Chains Carbons compounds can be as small as a few carbon atoms, or as large as a few thousand atoms. The larger molecules are called macromolecules. Cells are able to build macromolecules by bonding smaller molecules together into chains called polymers.

Types Of Organic Compounds Carbohydrates Lipids Proteins Nucleic Acids

CARBOHYDRATES An organic compound composed of carbon, hydrogen and oxygen. There are 2 H for every 1 O and 1 C. For Example:C2H4O2 Use: To store and release energy.

TYPES OF CARBOHYDRATES Saccharide = Sugar Monosaccharides Disaccharides Polysaccharides

Monosaccharides One sugar molecule A simple sugar Examples: Glucose Fructose

Disaccharides A two sugar carbohydrate Two monosaccharide sugars bond together. Example: When fructose and glucose bond Sucrose is formed. (aka table sugar)

Polysaccharides Poly = many The largest carbohydrates, polymers composed of many monosaccharides. Examples: Starch, cellulose, and glycogen Starch is made of highly branched chains of glucose molecules. Used as food storage by plants. Glycogen: energy storage for animals Cellulose: forms the walls of plants

Lipids: Fats & Oils Organic compounds that have a large quantity of C-H bonds, but less O than carbohydrates. Use: long term energy storage Insulation Protective coatings Major component of membranes

Properties of Lipids Insoluble- do not dissolve in water

Types of Lipids SATURATED Solid at Room Temperature Double bonds Animal based products Examples: Fats in Butter & Steak UNSATURATED Liquid at Room Temperature Single bonds Plant based products Examples: Peanut oil Corn oil Olive oil

Proteins A large, complex organic polymer composed of Amino Acids. Consist of C, H, O, N, and S Use: The building blocks of structural components 1. Muscle contraction, 2. transporting oxygen, 3. immunity and 4. chemical reactions

Amino Acids Proteins are long chains of amino acids. There are 20 amino acids. Amino acids are linked together by a peptide bond.

Enzymes Type of protein that speeds up chemical reactions.

Nucleic Acids Organic polymers composed of nucleotides. Consist of C, H, O, N, and P. Use: Store hereditary information. Control cell function Store information to make proteins.

Types of Nucleic Acids DNA (Deoxyribonucleic acid) RNA (ribonucleic acid) Contain instructions for life.

Nucleotides A Nucleic Acid is made up of many nucleotides. Nucleotides are made of: A sugar A Nitrogen Base A Phosphate Group

ATP = Energy ATP (Adenosine triphosphate) Carries energy in cells One nucleotide Two energy- storing phosphate groups Carries energy in cells