Ch. 2 Water, Biochemistry, and Cells Flashcards
life
growth, movement, reproduction, repose to external and internal stimuli, and can maintain homeostasis
universal solvent, polar
water
polarity
poles have different charges.
electronegative
more attractive to electrons. O2 is more so and pulls electrons closer when bonded to H2. creates partial charges. (O2 partially negative and H2 partially positive
hydrogen bond
weak bond between adjacent water molecules from partial charges
cohesion
tendancy for molecules to stick together. reason water is so difficult to heat.
reaction of an acid and a base
salts
hydrophobic
non polar
hydrophilic
polar
measure of acidity or basic. determined by concentration of H+ ions
pH scale
different energy levels based on distance from nucleus
electron cloud
electron shell
1st level. can hold 2 electrons
2nd and 3rd energy shell
can hold 8 electrons each
outermost energy level. where bonding occurrs. atoms with same number electrons in this show similar chemical behavior
valence shell
atoms share electrons. usually atoms with 4-5 e-
covalent bond
atoms take/receive e-. usually atoms with 1-3 and 6-7 e-. creates positive and negative charged ions
ionic bond
CH2O ratio. mono, dia, and polysaccharides
carbohydrates. mono and diasaccharides=simple sugars (glucose and sucrose)
polysaccharides=complex sugars (fructose)
chains of amino acids. 50% dry weight of cells
protein