AP Bio - Unit 2

covalent bond

strong bond between two atoms - intramolecular

• nonpolar - pair of e- shared equally by 2 atoms

• polar - e- shared unequally

• stable

• forms molecules

hydrogen bond

weak attraction of one water molecule another

• intermolecular

• polar water creates molecular attractions

ionic bond

attraction between two oppositely charged ions

specific heat

amount of energy required to heat 1g of substance to 1 degree C

• ex: 4.184J /gC - water, 0.84 J/gC - metal

resistance to temperature - hard to heat = hard to cool

• water moderates temperature on Earth

surface tension

cohesion - resistance to surface breakage

• water is “sticky”

adhesion

H bonding between H2O + other substances - water sticking to other things

• capillary action

cohesion

H bonding between H2O - water sticking to itself

heat of vaporization

takes lots of energy to get water to move from liquid → gas - taking heat with it (hottest molecules)

• evaporative cooling

hydrophobic

water fearing - don’t dissolve in water well

non-polar - hydrocarbon chain

hydrophilic

water liking -

water density (ice vs water)

solid is less dense than its liquid form (ice floats)

pH scale/H+ ion

ionization

• H+ splits from H2O, leaves OH-

  • [H+] > [OH-] - acidic

  • [H+] = [OH-] - neutral

  • [H+] < [OH-] - basic

pH scale

• 1 = acidic, 7 = neutral, 14 = basic

• 2 = 10x 1, 3 = 100x 1

• buffers control pH - resist change

hydroxyl group

organic compounds with OH = alcohols increase polarity

tons found in sugars

form H bonds easily = soluble in water

-OH

…C-C-O-H

carboxyl group

acids = donate H+ into solutions

fatty acids → lipids

amino acids → proteins

-COOH

carbonyl group

double bonded C with O - increase polarity

also helps with solubility in water

lots in sugars

C=O

amino group

amines acts as base - pulls H+ out of solutions

amino acid → protein

-NH2

-NH3+

phosphate group

transfers energy between organic molecules

lots of negative charge (highly reactive)

easily ionizes

DNA, RNA, ATP

-PO4

sulfhydryl group

helps with stabilization, especially in protein structure

tertiary structure

some amino acid r-groups

-SH

polymer

long molecules built by linking repeating building blocks in a chain

monomer

building blocks for polymers

condensation/dehydration reaction

joins monomers by “taking” H2O out

• one monomer donate OH-

• other donates H+

• together form H2O

hydrolysis reaction

uses H2O to break down polymers

• reverse of dehydration synthesis

• clears off one monomer at a time

• H2O is split into H+ and OH-

  • H+ and OH- attach to ends

monosaccharide

simple 1 monomer sugars

• ex: glucose

glycosidic linkage

polysaccharide

large polymers

-ex: starch

fatty acid

triacylglyercol/triglyceride

ester linkage

phospholipid

• glyceral + 2 fatty acids + PO4 ← negatively charged (polarity)

• found in cell membrane

  

steroid

amino acid

peptide bond

primary structure

secondary structure

tertiary structure

quaternary structure

denaturation

DNA

nucleotide

enzyme

activation energy

catalyst

substrate

product

active site

cofactors

competitive inhibitor

non competitive inhibitor

allosteric site

feedback inhibition

atoms and valence

25 elements essential for life

• 4 make up 96% of living matter

  • C, H, O, N

valence shell - outer most e-

• guide reactions