UNIT 1B

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

-different biological functions

structural isomers

-differ in covalent arrangement of atoms

geometric isomers

-same covalent relationships by different spatial arrangements

enantiomers

-isomers that are mirror images of each other

-structural differences create important functional significance

functional groups

-substitute other elements for hydrogen

-parts of organic molecules that are involved in chemical reactions

-give organic molecules distinctive properties

-affect reactivity

~make hydrocarbons hydrophilic

~increase solubility in water

macromolecules

-by joining carbon to other elements, we form the basis of life

-smaller organic molecules join together to form larger molecules

polymer

-a long molecule consisting of similar or identical building blocks

-blocks known as monomers

-joined through covalent bonds

-dehydration synthesis

synthesis

-joins monomers by "taking" H2O out

-one monomer donates -OH

-other monomer donates H+

-together these form H2O

-requires energy and enzymes

-condensation reaction

digestion

-use H2O to breakdown polymers

-reverse of dehydration synthesis

-cleave off one monomer at a time

-H2O is split into H+ and -OH

-requires enzymes

-releases energy

-hydrolysis

carbohydrates

-composed of C, H, O

-function: energy, raw materials, energy storage, and structural storage

-monomer: sugars

sugars

-all have carbonyl group and multiple hydroxyl groups

-location determines whether it is an aldehyde or ketone

-most names end in -ose

-classified by number of carbons

-when in solution, 5C and 6C structures form rings

monosaccarides

-simple one monomer sugars

-ex: glucose

disaccharides

-2 monomer sugars

-ex: sucrose

polysaccharides

-large polymer sugars

-ex: starch

sugar polymers

-costs little energy to build