Biology- Chapter 2 Flashcards

10760709876	Atom	The basic unit of an element that retains the properties of the element.	0
10760709877	Proton	Positively charged subatomic particle found in the nucleus of an atom; equal to the number of electrons in an electrically neutral atom.	1
10760709878	Neutron	A neutrally charged subatomic particle found in the nucleus of an atom.	2
10760709879	Electron	A negatively charged subatomic particle found orbiting the nucleus of an atom; equal to the number of protons in an electrically neutral atom.	3
10760709880	atomic mass	consists of the weight of protons and neutrons together	4
10760709881	Atomic Nucleus	The portion of an atom which contains protons and neutrons.	5
10760709882	Orbital	The volume of space an electron occupies.	6
10760709883	Energy Shells	Represent the state of potential energy of an electron. Those closer to the nucleus have the least amount of energy.	7
10760709884	Valence Shell	The outermost shell of an atom which controls the bonding of the atom	8
10760709885	Valence electrons	Electrons in the valence, or outermost, energy shell of an atom, which have the most potential energy and which can form bonds with other atoms.	9
10760709886	Isotopes	Atoms of the same element that have different numbers of neutrons	10
10760709887	Chemical bonds are	Attractions between atoms resulting from a sharing of valence electrons or the presence of opposite charges on the atoms. The bonded atoms gain complete valence shells.	11
10760709888	Covalent Bond	The sharing of a pair of valence electrons by two atoms.	12
10760709889	Molecule	Two or more atoms held together by covalent bonds.	13
10760709890	Single Bond	One pair of shared electrons. Example: hydrogen.	14
10760709891	Double Bond	Two pairs of shared electrons. Example: Oxygen has 6 electrons in its valence shell, which can hold 8. Each atom shares 2 electrons for a total of 4.	15
10760709892	Valence	An atom's bonding capacity, or the number of covalent bonds the atom can form to give the atom a full complement of electrons in the valence shell. Usually equals the number of unpaired electrons required to complete the valence shell.	16
10760709893	Electronegativity	The attraction of a particular atom for the electrons of a covalent bond. Atoms in a molecule attract shared bonding electrons to varying degrees. This degree is _________.	17
10760709894	Nonpolar Covalent Bond	A covalent bond between 2 atoms of the same element in which the electrons are shared equally because the two atoms have the same electronegativity.	18
10760709895	Polar Covalent Bond	a type of covalent bond where a pair of electrons is unequally shared between two atoms. example: water	19
10760709896	Ionic Bonds	Bonds between two atoms where one atom strips an electron completely away from its partner.	20
10760709897	Ion	One of two charged atoms resulting from an ionic bond.	21
10760709898	Cation	A positively charged ion	22
10760709899	Anion	A negatively charged ion	23
10760709900	Ionic compounds	Compounds formed by ionic bonds.	24
10760709901	Stable or Inert Atom	An atom with a full valence shell	25
10760709902	Hydrogen Bonds	Relatively weak bonds formed due to the mutual attraction of two electronegative atoms to hydrogen.	26
10760709903	Compound	A substance consisting of two or more elements in a fixed ratio.	27
10760709904	Element	A substance that cannot be broken down into other substances by chemical reactions.	28
10760709906	Radioactive Isotopes	An unstable isotope with a nucleus that decays spontaneously, emitting particles and energy. Used in fossil dating (Carbon-14 or 14C)	29
10760709907	Two or more atoms held together by a covalent bond consistute a _________.	Molecule	30
10760709909	Structural Formula	Uses bond symbols to show shared electrons between atoms.	31
10760709910	Molecular Formula	A formula showing the type of element and number of atoms only.	32
10760709911	van der Waals interactions	Weak attractions between molecules or parts of molecules that result from transient local partial charges.	33
10760709912	Chemical Reactions	The making and breaking of chemical bonds, leading to changes in the composition of matter.	34
10760709913	Reactants	The starting materials in a chemical reaction.	35
10760709914	Products	The ending materials in a chemical reaction.	36
10760709915	Chemical Equilibrium	The point at which chemical reactions offset one another and the forward and reverse reaction rates are equal.	37
10888543697	C, H, O, N	The elements make up 96% of living organisms	38
10888560640	sulfur	Which element is found in animals, but not in plants?	39
10888569566	Carbohydrates	the starches and sugars present in foods	40
10888573298	lipids	Energy-rich organic compounds, such as fats, oils, and waxes, that are made of carbon, hydrogen, and oxygen.	41
10888577507	protein	a macro-molecule that contains carbon, hydrogen, oxygen, and nitrogen; needed by the body for growth and repair	42
10888587283	nucleic acids	building blocks of DNA and RNA	43
10888599667	monomer	A simple compound whose molecules can join together to form polymers	44
10888613060	made of hydrocarbons	What does organic mean in biology?	45
10888624619	amino acids	building blocks of proteins	46
10888629438	Monosaccharides	simple sugars, they are the building blocks of carbohydrates	47
10888640385	Nucleotide	The building block of a nucleic acid	48
10888753014	cohesion of water molecules	During our lab, what forces caused the paperclip to float on water?	49
10888774141	adhesion	An attraction between molecules of different substances	50
10888794243	Hydrogen bonds are	What property of water causes it to be cohesive?	51
10891837403	Mixture	A combination of two or more substances that are not chemically combined	52
10891858349	Suspension	A mixture in which particles can be seen and easily separated by settling or filtration example: blood	53
10891870409	pH scale	scale with values from 0 to 14, used to measure the concentration of H+ ions in a solution; a pH of 0 to 7 is acidic, a pH of 7 is neutral, and a pH of 7 to 14 is basic	54
10891878585	A base has a pH ...	pH greater than 7 example: Baking soda	55
10891901219	An acid is a substance that _____.	increases the hydrogen ion concentration of an aqueous solution pH less than 7	56
10891918585	Buffer	A solution that minimizes changes in pH when extraneous acids or bases are added to the solution.	57
10891929179	Polymer	A long molecule consisting of many similar or identical monomers linked together.	58
10891946062	amino acid	Building blocks of protein	59
10892017481	chemical reaction	the process by which one or more substances change to produce one or more different substances	60
10892023804	Reactant	A chemical substance that is present at the start of a chemical reaction	61
10892031820	product	a substance that forms in a chemical reaction	62
10892041258	activation energy	Energy needed to get a reaction started	63
10892046337	catalyst	substance that speeds up the rate of a chemical reaction	64
10892052042	Enzyme	A type of protein that speeds up a chemical reaction in a living thing	65
10892057962	Substrate	The reactant on which an enzyme works.	66
10892073198	endothermic reaction	A reaction that ABSORBS energy in the form of heat	67
10892080528	exothermic reaction	A reaction that releases energy in the form of heat	68