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Bio Notes

REVIEW UNIT 1-THE CELL LIFE *There is no def. for life *Life can be characterized by a list of things that we might agree living thing have in common-organized and contain complex chemical substances, Made up of one or more cells, Use Energy, Have a definite form& Limited size, Have a limited life Span, Grow, Respond to changes in the environment, Reproduce, Evolve over time.*Metabolism is all the chemical reaction occurring
in the cell of an organism*All Living things must carry out processes to maitain life and homeostasis- Nutrition, Transport, Respiration, Synthesis and Assimilation, Growth, Excretion, Regulation, Reproduction, Metabolism.CHEMISTRY BASICS *Atoms of the elements are the basic unit of mattter and are composed of protons, neutrons and electrons.*Atomic mass is the sum of the number of protons and nuetrons in an atom.*The number of protons and electrons is the same as the atomic number.*Isotopes of an element differ in the number of nuetrons,*The outer most electrons of an atom are called valence electrons and are evolved in chemical bonding.*Covalent bonds between elements involve the sharing of a pair of electrons. *Transferring an electron betwwen atoms and then the pos. and neg. charged atoms bonding together by charge forms ionic bonds. *2 adjacent molecules sharing ahydrogen atom forms hydrogen bonds*A chemical formula indicates the type and number of elements in a molecule.* A structural formula indicates the type, number, and bonding between elements in a molecule.*Chemical reaction are composed of reactants and products and the number of atom of elements of the reactants must equal the # of elements in the products, i.e. Chemical equations must be balanced in the number of elements.* Mixure are composed of different substances that are not chemically bonded,*Mixures where substances are mixed but exist as individual molecules are called solutions. TRhe subst. making up the bulk of the mixure is called the solevent and the other...