Study Guide for AP Biology Unit 1 Test Exam and 100% Correct Solutions

Study Guide for AP Biology Unit 1 Test Exam and 100% Correct Solutions water - CORRECT ANSWER--polar molecule -polar colvalent bonds -oxygen end is partial negative and the hydrogens have a partially positive end -cohesive polar covalent bonds - CORRECT ANSWER--opposite ends of the molecule have opposite charges cohesion - CORRECT ANSWER--H bonding between H2O creates it (sticky) -allows for the movement of water against gravity -high surface tension -water moves up a tree by transpiration (helped by ____) adhesion - CORRECT ANSWER--H2O molecules form H bonds with other substances ~capillary action ~meniscus ~water climbs up fiber solvent - CORRECT ANSWER--water is the universal one -polar water molecules will surround the (+) and (-) ions causing the ions to separate and dissolve -dissolve solutes and create aqueous solutions hydrophilic - CORRECT ANSWER--some molecules have an affinity for water -polar and ionic molecules -ex: cotton, cellulose, paper hydrophobic - CORRECT ANSWER--some substances do not have an affinity for water -nonpolar and non ionic substances -ex: fat, glycerol, oils floats - CORRECT ANSWER--less dense when it is solid, water ______ -forms crystal lattice structure -important because oceans and lakes do not freeze solid ~insulates water below ~seasonal turnover of lakes specific heat - CORRECT ANSWER--the amount of heat that must be absorbed or lost for 1g to change its temperature by 1C -water had high _____ due to H bonding -resists change in temp -moderates temp on earth evaporative cooling - CORRECT ANSWER--organisms use to regulate their temperature -ex: sweating -water evaporates through a surface, cooling occurs acidic - CORRECT ANSWER-If [H+][-OH] basic - CORRECT ANSWER-If [-OH][H+] pH scale - CORRECT ANSWER--how acidic or basic a solution is -pure water, only 1 molecule in every 554 million is dissociated -most biological fluids have 6-8 -each unit represents a 10-fold difference in H+ and -OH concentrations neutral - CORRECT ANSWER--If concentration of 2 ions is equal carbon - CORRECT ANSWER--all life mostly based on this element -important due to its electron configuration ~able to make 4 stable covalent bonds (tetra valence) ~very versatile -tetravalence allows them to be strung together in chains hydrocarbons - CORRECT ANSW