AP Biology Unit 1 Test QUESTIONS
WITH VERIFIED, 100% ACCURATE
ANSWERS— GRADED A+
water ✔✔-polar molecule
-polar colvalent bonds
-oxygen end is partial negative and the hydrogens have a partially positive end
-cohesive
polar covalent bonds ✔✔-opposite ends of the molecule have opposite
charges
cohesion ✔✔-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 ✔✔-H2O molecules form H bonds with other substances
~capillary action
~meniscus
~water climbs up fiber
solvent ✔✔-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 ✔✔-some molecules have an affinity for water
-polar and ionic molecules
-ex: cotton, cellulose, paper
hydrophobic ✔✔-some substances do not have an affinity for water
-nonpolar and non ionic substances
-ex: fat, glycerol, oils
floats ✔✔-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 ✔✔-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 ✔✔-organisms use to regulate their temperature
-ex: sweating
-water evaporates through a surface, cooling occurs
acidic ✔✔If [H+]>[-OH]
, basic ✔✔If [-OH]>[H+]
pH scale ✔✔-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 ✔✔-If concentration of 2 ions is equal
carbon ✔✔-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 ✔✔-combinations of C and H
-nonpolar
~not soluble in water
~hydrophobic
-stable
-very little attraction between molecules
-gas at room temp
isomers ✔✔-molecules with the same molecular formula but different
structures
-different chemical properties
WITH VERIFIED, 100% ACCURATE
ANSWERS— GRADED A+
water ✔✔-polar molecule
-polar colvalent bonds
-oxygen end is partial negative and the hydrogens have a partially positive end
-cohesive
polar covalent bonds ✔✔-opposite ends of the molecule have opposite
charges
cohesion ✔✔-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 ✔✔-H2O molecules form H bonds with other substances
~capillary action
~meniscus
~water climbs up fiber
solvent ✔✔-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 ✔✔-some molecules have an affinity for water
-polar and ionic molecules
-ex: cotton, cellulose, paper
hydrophobic ✔✔-some substances do not have an affinity for water
-nonpolar and non ionic substances
-ex: fat, glycerol, oils
floats ✔✔-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 ✔✔-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 ✔✔-organisms use to regulate their temperature
-ex: sweating
-water evaporates through a surface, cooling occurs
acidic ✔✔If [H+]>[-OH]
, basic ✔✔If [-OH]>[H+]
pH scale ✔✔-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 ✔✔-If concentration of 2 ions is equal
carbon ✔✔-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 ✔✔-combinations of C and H
-nonpolar
~not soluble in water
~hydrophobic
-stable
-very little attraction between molecules
-gas at room temp
isomers ✔✔-molecules with the same molecular formula but different
structures
-different chemical properties
