water & molecules Flashcards
elements in carbohydrates
C H & O
elements in lipids
C H & O
elements in proteins
C H O N & S
elements in nucleic acids?
C H O N & P
“polymers” definition
long chains of monomers in repeating units
“ionic bonds”
atoms give / receive electrons to form bonds
“covalent bonds”
atoms share electrons to bond
“polar”
to have regions of negativity and positivity
why is water polar?
hydrogen pos oxygen neg = one atom will be more pos / neg than the other = polar
how do hydrogen bonds form?
regions of positive and negativity will attract each other and form bonds = h bonds that constantly form and reform (weak)
benefits of water as a polar molecule?
- acts as a solvent for many solutes
- medium for reactions
- transport of dissolved compounds in and out cell
benefits of cohesive water?
efficient transport medium bc capillary action via cohesion (to each other) and adhesion (to other polar molecules)
characteristics of water
- unusually high bp (h bonds require high energy to break to become gaseous)
- ice more dense than water (h bonds fix polar molecules further apart in ice = giant rigid open structure = more dense
- cohesive (moves as one mass bc molecules attracted to each other)
- adhesive (H2O molecules attracted to each other)
benefits of water as a coolant?
helps buff temp changes in cell reactions + maintains temp for enzymes
stable environment for organisms bc doesn’t change temp easily + ice forms on top first = insulating layer on lakes etc + surface tension holds small bugs
“ions”
total number of electrons does not equate to protons
