Unit 1 Chemistry of Life - Water Properties and Macromolecules

adhesion

the attraction of water molecules to other, non-water substances

cohesion

The attraction of water molecules to themselves (contributes to surface tension)

surface tension

the strong cohesion and inward pull of water molecules at the surface, making it resist external force and get the smallest area possible

covalent bond

the chemical link where two atoms share electrons

dipole moment

when O pulls more shared electrons to itself causing O partial negative charge and H partial positive charge

polarity

unequal/opposite distribution of positive and negative charges

polar molecule

a molecule that has positive and negative charges caused by uneven distributions

electronegativity

how strongly an atom attracts shared electrons in a chemical bond

capillary action

process of a liquid flowing through a narrow space or porous material against an opposing force like gravity. adhesion greater than cohesion, and surface tension allows water to keep its shape

hydrogen bond

bond linking water molecules due to their polarity

high specific heat

the specific temperature (amount of energy) needed to rise 1g water by 1 degree C

Heat of vaporization

The energy required for liquid water molecules to become gas. Water has a high heat of vaporization.

evaporative cooling

Cooling that occurs when high-energy water molecules evaporate, leaving behind lower-energy molecules.

solvent

substance that dissolves another substance (e,.g. water)

hydrophobic

substances that don’t mix well/dissolve/stick to water

hydrophilic

substances that interact well/dissolve well in water

pH level of 7

concentration of H+ and OH-ions are equal

pH increase

concentration more OH-, less H+

pH decrease

concentration more H+, less OH-

Carbon

main earth-life element, can form 4 covalent bonds

organic molecules

come from living things, featured C atoms bonded to one another w/ H, O, N, etc.

macromolecules

biological molecules that all contain CHO

carbohydrates’ elements

CHO

proteins’ elements

CHONS, (S for disulfide bonds)

lipids elements

CHOP, (P in phospholipid)

nucleic acids’ elements

CHONP (P for PO4 and N for nitrogenous base)

purpose of carbon based molecule

b/c carbon based molecules in food, food fuel for NRG, food makes up the molecules in our cells that are US

metabolism

buildup/breakdown of large molecules and small ones (catabolism, anabolism)

polymer

large molecule made of small subunits

monomer

small subunits of larger molecule

hydrolysis

chemical rxn breakdown polymer into monomer by adding H2O

dehydration synthesis

monomer turn into polymer through covalent bond by taking OH- one group and H from another

polymerization

many momomers linked to form polymer

carbs

organic molecules containing CHO, carbon atoms bonded to -OH and H for fuel and structure

monosaccharides

monomers of carbs (e.g. glucose, fructose)

polysaccharides

complex sugars/carbs (many monosac. joined tgt)

cellulose

linear polys. that forms plant cell walls + can’t be broken down by H2O

starch

linear/branched plant glucose for plant NRG storage

glycogen

how animals and US store glucose for NRG in liver/muscle

lipids

group of non-polar/hydrophobic organic molecules w/ diff function depending on assemblance put tgt

fatty acids

a lipid monomer found in fats and phospholipids

saturated fatty acid

only single bonds between Cs, solid at room temp

unsaturated fatty acid

has 1+ double bonds between Cs, liquid at room temp

fats

lipids responsible for NRG storage, cell function, insulation for mammals

steroids

lipid molecule used to make hormones

cholesterol

lipid that is used to stabilize animal cell membrane and fluidity

phospholipids

lipid that makes up the lipid bilayer in membranes, contains phosphate groups

nucleic acid

macromolecule containing genetic info based on monomer sequence

DNA and RNA

made of nucleotide monomers, sequence determines msgs cell can read

nucleotide structure

contains PO4, nitrogenous base (ATGC), 5 carbon sugar (deoxyribose/ribose)

how nucleotides added

starts from 5’, more nucleotides adds onto 3’ (strands built 5’→3’), held with covalent bonds

DNA

2 nucleotide strands that are antiparallel and form a double helix, form ATGC in middle through hydrogen bonds, deoxyribose

RNA

1 strand nucleotide, AUGC, has ribose

proteins

organic macromolecule made of 20 diff amino acids

amino acid

monomer of proteins - contains amino group, (n-terminus NH2), carboxyl group (c-terminus COOH), and R group side chain

polypeptide

amino acid chain

peptide bond

covalent bond linking amino group of an AA and carboxyl group of another AA

R group

determine AA, their interaction determine structure + function of whole protein

R group variations

can be hydrophobic/nonpolar, hydrophilic/polar, + and - charged

primary structure

sequence of AA in protein

secondary structure

how protein fold due to hydrogen bonds in N-H and C=O interacting with each other (pH can disrupt this)

tertiary structure

how R group interact with each other which determines 3D shape of protein

hydrophobic interactions

between 2 nonpolar R groups

disulfide bridges

between 2 S containing groups

R group hydrogen bonds

between 2 polar R groups

ionic bonds

between 2 oppositely charged R groups

quaternary structure

determined by many polypeptide subunits’ interactions