BIOL 203 Exam 1 - Purdue University Test Questions With Well Elaborated Solutions

BIOL 203 Exam 1 - Purdue University Test Questions With Well Elaborated Solutions How did life originate on earth? - ANSWER -- primordial ocean - lightning or ultraviolet radiation - thermal vents or volcanos - meteorites - RNA World 4 major elements in the body - ANSWER -- Oxygen (65%) - Carbon (18%) - Hydrogen (10%) - Nitrogen (3%) 3 minor elements in the body - ANSWER -- Calcium (1.5%) - Phosphorus (1%) - Potassium (.35%) simple structure of an atom - ANSWER -composed of protons, neutrons and electrons proton - ANSWER -positively charged particle nuetron - ANSWER -no charge elecron - ANSWER -negatively charged particle atomic number - ANSWER -the number of protons in the nucleus of an atom atomic weight - ANSWER -the number of protons plus the number of neutrons ion - ANSWER -if an atom loses or gains an electron it becomes a positive or negative ion cation - ANSWER -a positively charged ion anion - ANSWER -a negatively charged ion isotope - ANSWER -atoms of the same element that have different numbers of neutrons 4 types of atomic bonds - ANSWER -covalent, ionic, hydrogen, van der waals force covanlent bond - ANSWER -a pair of shared electrons between two atoms ionic bond - ANSWER -the attraction between oppositely charged ions hydrogen bond - ANSWER -weak attraction between a hydrogen atom and another atom van der waals force - ANSWER -short-range attractions between atoms and molecules molecule - ANSWER -group of two or more atoms held together by chemical bonds simple formulas - ANSWER -elemental abbreviation and amount of each structural formulas - ANSWER -chemical formulas that show the arrangement of atoms in molecules synthesis reaction - ANSWER -amino acids are formed with a covalent bond to form a protein Dissociation or Decomposition Reactions - ANSWER -a molecule compound breaks down into its original molecules Exchange Reaction - ANSWER -AB + CD -- AD + CB Reversible Reactions - ANSWER -chemical reaction is reversed acids - ANSWER -release hydrogen ions when dissolved in water bases - ANSWER -release hydrogen ions when dissolved in water salts - ANSWER -the result of an amino acid reacting with water electrolytes - ANSWER -substances that are bonded together by a electrovalent bond and dissociate into separate ions when dissolved in water sodium chloride reaction - ANSWER -1.) dissociates into Na+ and OH- and H+ and Cl- 2.) the OH- then combines with the H+ to form H2O 3.) if we evaporated the water the Na and Cl ions would combine with an electrovalent bond and form solid crystals of NaCl pH - ANSWER -hydrogen ion concentration acidic solution - ANSWER -pH below 7 alkaline solution (basic) - ANSWER -pH above 7 neutral - ANSWER -pH of 7 pH of blood - ANSWER -7.4 4 major inorganic substances - ANSWER -water, carbon dioxide, sodium chloride, oxygen organic substances - ANSWER -carbohydrates, lipids, proteins, nucleic acids carbohydrates - ANSWER -sugars (monosaccharides, disaccharides, polysaccharides) monosaccharides - ANSWER -simple sugars (glucose, fructose, galactose) disaccharide - ANSWER -A double sugar, consisting of two monosaccharides (sucrose, lactose) polysaccharides - ANSWER -large macromolecules formed from many monosaccharides (glycogen, starch) lipid - ANSWER -Energy-rich organic compounds, such as fats, oils, and waxes, that are not soluble in water (triglycerides, phospholipids, steroids)