Unit 1 - The Chemistry of Life

hydrogen bonding

partially positive hydrogen atom in one polar covalent molecule will be attracted to an electronegative atom in another polar covalent molecule 

intermolecular bond

bond that forms between molecules

polar covalent bond

when electrons are not being shared equally between atoms (hydrogen pairing w an electronegative)

what bond is between water molecules

hydrogen bonds

polarity

unequal sharing of electrons (happens in water)

cohesion

attraction of molecules for other molecules of the same kind, forces increases due to hydrogen bonds between water molecules holding them together

surface tension

property of allowing liquid to resist external force (cohesion is responsible for it)

what helps water and nutrients travel against gravity in plants

cohesion and capillary action

adhesion

clinging of one molecule to a different molecule, due to water polarity, allows water to cling onto walls in plants

capillary action

upward movement of water due to the forces if cohesion, adhesion, and surface tension, occurs when adhesion id greater than cohesion

transpiration

transport if water and nutrients in plants, adhesion needs to be greater than cohesion

high specific heat (temp control)

water resists in temp due to hydrogen bonds (the bonds release heat when forming and the heat must be absorbed to break those bonds)

evaporative cooling

high heat of vaporization

what do the molecules with the highest kinetic energy leave as

gas

what helps moderate earths climate, stabilize temp in bodies of water, and prevent terrestrial organisms from overheating (ex. sweating) and leaves from becoming too warm in the sun

evaporative cooling

less dense as solid

when water solidifies (freezes), it expands and becomes less dense, due to hydrogen bonds because when water molecules are cooled, they move slowly to break the bonds

what allows marine life to survive under floating ice sheets

water density when solid

what structure does the hydrogen bonds in water molecules form?

crystalline structure

universal solvent

aka versatile solvent, due to polar molecules being attracted to ions and forming hydrogen bonds

solution, solvent, solute

ex. saltwater, water, salt

ionic compounds

partially negative oxygen (or hydrogen) in water interacts with a positive (or negative) atom, dissolves ions

hydrophillic

water lover, polar and/or ionic bonds

hydrophobic

water hater, fats (oils) dont dissolve in water

dehydration reaction

bonds two monomers with the loss of water (h2o), a+b→AB + h2o

hydrolysis

breaks the bonds in a polymer by adding water

isomers

same formula, different structure (making a diff func)

carbohydrates

sugars and polymers of sugars, main energy source for living things

monosaccharides

carbohydrate monomers or simple sugars, 1:2:1 ratio (ch2o), ex. glucose, raw material for building molecules, linear skeletons,

polysaccharides

carbohydrate macromolecules or polymers of sugars, structure n func is determined by its sugar monomers and positions of glycosidic linkages, function as storage or structural polysaccharides

1:2:1 ratio, molecular formula

monosaccharides

dissaccharide

formed when a dehydration reaction joins two monosaccharides, covalent bond in it is called glycosidic linkage

synthesis of maltose

dehydration reaction

starch

storage polysaccharide of plants, made up of glucose monomers

leucoplast/amyloplasy

plants store surplus starch as granules within an organelle

glycogen

storage polysaccharide in animals, humans and other vertebrates store glycogen mainly in love and muscle cells

cellulose

polysaccharide, major component in tough plant cell walls

helical, straight

polymers with a configuration, b confuguration

chitin

polysaccharide, found in exoskeleton of arthopods (shellfish)

lipids

store energy in living things, hydrophobic bc they consist mainly of carbon and hydrogen (non polar covalent bonds), ex. fats, phospholipids, steroids

fatty acids

monomer of lipids, consists of a carboxyl group attached to a long carbon skeleton

glycerol

monomer of lipid, a three carbon alcohol with a hydroxyl group attached to each carbon

triglycerides/tryglycerol

3 fatty acids joined to a glycerol by an ester linkage

saturated fatty acid

maximum number of hydrogen atoms possible and no double bonds

unsaturated fatty acid

has one or more double bond

lard, butter, bacon grease

saturated, solid at room temp, no double bonds, most animal fat

corn, olive oil

unsaturated fat, one or more double bonds between carbons, liquid at room temp, plant fats

trans fat

converting unsaturated fat into saturated (hydrogenation), very bad for you

adipose tissue

cushions vital organs and insulates body, made of fat

phospholipid

two fatty acids and a phosphate group are attached to glycerol, bilayer, apart of all cell-membranes

steroids

hormonal lipids, ex. cholesterol in animals

waxes

esters made of an alcohol chain and a fatty acid chain, plants have this to prevent water loss

nucleotides

monomers of nucleic acids, consists of a nitrogenous base, a 5 carbon sugar (pentose, and a phosphate group

deoxyribose, ribose

sugar in DNA, sugar in RNA

nucleoside

nitrogenous base and sugar

pyrimidines

cytosine, thymine, uracil (rna only), single rings

purines

adenine, guanine, double rings

3’ and 5’ ends

if it starts as a right side up pentagon, top is 5’, end is 3’

gene

series of bases that code for a particular trait

double helix

dna structure, strands or bases are held together by hydrogen bonds

enzyme

type of protein that acts as a catalyst to speed up chemical reactions

amino acids

organic molecules with carboxyl and amino groups

R groups

amino acids that differ in their properties due to differing side chains

peptide bonds

amino acids are linked by them

polypeptide

polymer of amino acids

proteins

consist of polypeptides folded into a 3d shape, shape determines function

peptide bond formation

carboxyl group of one AA must be positioned next to the amino group of another AA

primary structure

a sequence of amino acids, bonded by peptide bonds, chain shape

secondary structure

coils and folds that result from hydrogen bonds between amino acids in the backbone

alpha helix

coiled every 4th peptide bond

beta pleated sheet

folded, interchain H bonds

tertiary structure

interactions between R groups, bonded with hydrogen and ionic bonds, hydrophobic interactions, and van der Waals interactions, strong covalent bonds called disulfide bridges can reinforce the protein structure

quaternary structure

two or more polypeptide chains form one macromolecule, ex. collagen (fibrous protein) contains 3, ex. hemoglobin (globular protein) contains 4, two of each secondary struc