C HEMISTRY OF L IFE The Nature of Matter

T HE N ATURE OF M ATTER Matter is anything that has mass and takes up space (has volume). Everything around us is made of matter. Energy is anything that brings about change. - Can hold matter together - Can tear matter apart

M ATTER Examples: Atoms elements Living things Rocks Soil air

E NERGY Examples: Sunlight Electricity Heat Chemical energy

T HE N ATURE OF M ATTER Atoms – smallest defined unit of matter An atom has 3 parts : Proton is positive + Neutron has no charge Electron is negative - Electron is the part of atom involved in chemical reactions.

T HE N ATURE OF M ATTER – A TOM STRUCTURE Nucleus- center of atoms that contains neutrons and protons. Electrons orbit around the nucleus. Energy holds the parts of an atom together. There are different kinds of atoms depending on the number of electrons and protons.

T HE N ATURE OF M ATTER Elements – something that is made up of only one kind of atom. Elements can not be broken down into a simpler form. Ex: oxygen is made up of only oxygen atoms

T HE N ATURE OF M ATTER Everything is made up of elements. Most things, organisms included, are made of combinations of different elements. Example : air is made of many elements not just oxygen, but nitrogen, hydrogen, and carbon.

N ATURE OF M ATTER Compounds are made up of 2 or more elements. Compounds can look and act differently than the atoms they are made of. Example: Water (H20) is two hydrogen atoms bonded to one oxygen.

- Chemical Compounds in Cells E LEMENTS AND C OMPOUNDS Carbon dioxide, which is found in gas bubbles, is a chemical compound. So is water.

T HE N ATURE OF M ATTER There are two kinds of compounds. 1) molecules - atoms bond together by SHARING elections. 2) ion compounds - ion is an atom with a positive or negative charge.

T HE N ATURE OF M ATTER Ion compounds – are formed by the attraction of opposite ions. A positive and a negative ion form an ion compound Example: Salt is Sodium (Na) Chloride (Cl) ( Na+ and Cl-) = NaCl

O RGANIC C OMPOUNDS Always contain carbon and hydrogen and are usually associated with living things. 4 types make up living things: Carbohydrates Lipids Proteins Nucleic Acids

O RGANIC C OMPOUNDS CarbohydratesLipidsProteinsNucleic Acids FunctionSupply energy for cell processes; short-term Energy storage Store large amounts of energy long term; cell membranes Regulate cell processes and build cell structures Carry hereditary information; used to make proteins ElementCarbon, hydrogen, and oxygen Carbon, oxygen, hydrogen, phosphorous Carbon, oxygen, hydrogen, nitrogn, sulfer Carbon, oxygen, hydrogen, nitrogen, phos. ExampleSugars, starch, cellulose Fats, oils, waxes, and cholesterol Enzymes, skin, and hair DNA and RNA