BIOL181 WEEK 1 PRACTICE SET 2026 TESTED
MATERIAL RESOLVED A+
◉ integral membrane proteins. Answer: permanently associated w/
membrane
- unable to be separated
- hydrophilic AND hydrophobic regions
◉ peripheral membrane proteins. Answer: temporarily associated
w/ membrane
- internal or external
- weak noncovalent interactions w/ polar heads or integral proteins
- transmits info from external signals
◉ fluid mosaic model. Answer: proposes that lipid bilayer --> fluid
structure
- allows molec to move laterally within membrane
- mosaic of lipids/proteins
◉ FRAP. Answer: Fluorescent Recovery After Photobleaching
,◉ how does FRAP demonstrate the dynamic property of the plasma
membrane?. Answer: plasma membrane...
- regulates movement of molec into/out of the cell
- maintains homeostasis
(FRAP measures the fluidity of a membrane by shooting a laser that
bleaches fluorescent markers on the membrane & measures the
time of fluorescence as gradual recovery occurs)
◉ semipermeable membrane. Answer: (non-living)
excludes substances from crossing based on SIZE
◉ selectively permeable membrane. Answer: (living)
regulates what passes through based on SIZE, CHARGE, & POLARITY
◉ homeostasis. Answer: active regulation/maintenance of a stable
internal physiological state in the face of a changing environment
◉ 3 parameters that must be stably maintained inside a cell.
Answer: 1. pH
2. salt concentration
3. volume
, ◉ passive transport. Answer: movement of substances across a cell
membrane
- NO energy required
- moves from high --> low concentration gradient
◉ diffusion. Answer: movement of ALL SUBSTANCES from an area of
higher concentration --> lower concentration
◉ osmosis. Answer: net movement of a solvent (water) across a
selectively permeable membrane towards the side w/ higher solute
concentration
◉ tonicity. Answer: ability of extracellular solution to make water
move into or out of a cell by osmosis
◉ osmolarity. Answer: concentration of solutes in a solution
◉ hypertonic. Answer: higher osmolarity (shrivels--water out)
◉ hypotonic. Answer: lower osmolarity (swells--water in)
◉ isotonic. Answer: equal osmolarity
MATERIAL RESOLVED A+
◉ integral membrane proteins. Answer: permanently associated w/
membrane
- unable to be separated
- hydrophilic AND hydrophobic regions
◉ peripheral membrane proteins. Answer: temporarily associated
w/ membrane
- internal or external
- weak noncovalent interactions w/ polar heads or integral proteins
- transmits info from external signals
◉ fluid mosaic model. Answer: proposes that lipid bilayer --> fluid
structure
- allows molec to move laterally within membrane
- mosaic of lipids/proteins
◉ FRAP. Answer: Fluorescent Recovery After Photobleaching
,◉ how does FRAP demonstrate the dynamic property of the plasma
membrane?. Answer: plasma membrane...
- regulates movement of molec into/out of the cell
- maintains homeostasis
(FRAP measures the fluidity of a membrane by shooting a laser that
bleaches fluorescent markers on the membrane & measures the
time of fluorescence as gradual recovery occurs)
◉ semipermeable membrane. Answer: (non-living)
excludes substances from crossing based on SIZE
◉ selectively permeable membrane. Answer: (living)
regulates what passes through based on SIZE, CHARGE, & POLARITY
◉ homeostasis. Answer: active regulation/maintenance of a stable
internal physiological state in the face of a changing environment
◉ 3 parameters that must be stably maintained inside a cell.
Answer: 1. pH
2. salt concentration
3. volume
, ◉ passive transport. Answer: movement of substances across a cell
membrane
- NO energy required
- moves from high --> low concentration gradient
◉ diffusion. Answer: movement of ALL SUBSTANCES from an area of
higher concentration --> lower concentration
◉ osmosis. Answer: net movement of a solvent (water) across a
selectively permeable membrane towards the side w/ higher solute
concentration
◉ tonicity. Answer: ability of extracellular solution to make water
move into or out of a cell by osmosis
◉ osmolarity. Answer: concentration of solutes in a solution
◉ hypertonic. Answer: higher osmolarity (shrivels--water out)
◉ hypotonic. Answer: lower osmolarity (swells--water in)
◉ isotonic. Answer: equal osmolarity
