chapter 8 part 2; 8.6 osmosis and dialysis Flashcards
in a cell is the outer or inner membrane more permeable
outer
is the inner member soluble
no;
water and certain solutes
what are cell membranes composed of
phospholipids
how many membranes does the nucleus have
two; that separate the DNA from the rest of the cell
how many membranes does mitochondria have
two; separating the inner part from the cell’s cytosol
since the inner membrane is not really soluble, how are things supposed to cross the membrane
proteins passes
is the top of a phospholipid polar or nonpolar, hydrophobic or hydrophilic, and faced on the outside or inside
polar + hydrophilic
and face on the outside
is the ends of a phospholipid polar or nonpolar, hydrophobic or hydrophilic, and faced on the outside or inside
nonpolar
hydrophobic
faced on the inside
do kidneys also have selectively permeable membranes
yes; filter out waste from out bloodstream
can colloids (large particles suspended in the solvent) and larger particles cross a selectively permeable membrane
no; have to have another way of crossing
diffusion is random movement of [solute or solvent] particles through the [solute or solvent]
solute
solvent
diffusion results in […] concentration of the solute
uniform
two solutions of different concentration separated by a selectively permeable membrane creates a
concentration gradient
are concentration gradients present in cells
yes
what can make a gradient of concentration in a cell
certain ions present in higher concentrations outside of the cell compared to inside
e.g. sodium higher outside
e.g. potassium is higher inside
what are permeable substances that are able to readily diffuse
small non polar molecules
e.g. O2, N2, CO2
small polar molecules
e.g. H2O
to readily diffuse small molecules need to be [polar or non polar] and those that are polar need to be [large or small]
non polar
polar e.g. H2O
Small
what are permeable substances that need assistance (and sometimes energy)
larger polar molecules
e.g. C6H12O6
small monoatomic ions
e.g. Cl-. Na+. K+
when needing assistance and sometimes energy large molecules need to be [polar or non polar] and when being small ions they need to be […]
polar
monoatomic
e.g. ions with charge
what are the three factors that determine the diffusion across a semi permeable membrane
size (smaller size)
charge (neutral solutes)
polarity (polar molecules have a more difficult time than nonpolar)
side note; molecules with charges have a difficult time crossing
