BMS 260 Exam # 1 questions and
answers A+ rated
What is the M phase? - correct answer ✔✔The only non-biosynthetic phase. Here, the cell is
just dividing.
What is G0? - correct answer ✔✔This is the resting phase where most of the cells we talk about
reside.
What is G1? - correct answer ✔✔This is where all cellular materials (excluding genetic material)
is duplicated.
What is the S phase? - correct answer ✔✔This is where DNA synthesis occurs. Note: Agents may
bind to DNA to stop DNA synthesis.
What is G2? - correct answer ✔✔Microtubule inhibitors stop making cell components needed
to separate. The cell is double-checking to ensure it is ready for replication.
What is the Dynamic Regulatory Barrier? - correct answer ✔✔The plasma membrane; it
changes to regulate imports and exports and helps maintain homeokinesis (maintaining the
intracellular environment)
1972 Singer & Nicolson - correct answer ✔✔Described the plasma membrane as a phospholipid
bilayer
What are the components of a phospholipid? - correct answer ✔✔Phosphate head attached to
a carbon glycerol attached to a fatty acid tail.
,What kinds of proteins (general then specific) allow for cell-cell interactions? - correct answer
✔✔Integrins; cadherins
Spacing between desmosomes; What kind of particle movement is shown in this instance? -
correct answer ✔✔Around a 20nm space (not tight enough for stopping molecules);
paracellular movement (between the cells)
What are tight junctions and what kind of movement? - correct answer ✔✔These cause a
blockage of the extracellular pathway. Transcellular movement (in through and out of the cell
past the tight junction.
Pre-gut closure - correct answer ✔✔Tight junctions aren't tight enough and allow a lot of
paracellular movement
What are gap junctions, what are their spacings, and where are they very important? - correct
answer ✔✔They are tunnel-like junctions between cells. They are around 2-4 nm between cells
(with 1.5nm channels) and are very important in intercalated disks in the heart in transferring
information through the cells
Diffusion vs osmosis - correct answer ✔✔Diffusion is the movement of solute to reach
equilibrium whereas osmosis is the movement of solvent across the plasma membrane (from
high-->low conc.)
What is a flux? - correct answer ✔✔The flow of a something across a membrane
Which ways can flux go? What is a net flux? - correct answer ✔✔Flux can go both directions,
just more heavily down the gradient. A net flux is the overall movement of molecules taking into
account the reverse flux.
, What four factors determine the rate of diffusion - correct answer ✔✔Kinetic
energy/temperature within the molecule, permeability of the membrane, concentration
gradient, difference in membrane potential (elec. charge)
Facilitated diffusion, why does this happen, and what molecules primarily do this? - correct
answer ✔✔Moving things down the gradient with help of an intermediate carrier protein. This
happens when molecules are not compatible with the membrane (polar molecules).
GLUT-4 - correct answer ✔✔A carrier responsible for facilitated glucose movement in cells --
sodium dependent in kidneys
What impacts facilitated diffusion - correct answer ✔✔Concentration gradient and the
abundance of carrier proteins
What helps set up polarity of the plasma membrane? - correct answer ✔✔The sodium-
potassium ATPase pump
Secondary active transpory - correct answer ✔✔This uses the energy in an ion gradient to move
a second solute (eg. Sodium moves down its concentration gradient and takes along glucose or
AAs up its gradient)
Other examples: SGLT 1&2
How does phagocytosis work? - correct answer ✔✔Bigger objects are taken into membrane-
bound vesicles that fuse to the lysosome within the cell
What are Kuppfer cells - correct answer ✔✔Cells in the liver that are modified macrophages
that engulf cellular debris
answers A+ rated
What is the M phase? - correct answer ✔✔The only non-biosynthetic phase. Here, the cell is
just dividing.
What is G0? - correct answer ✔✔This is the resting phase where most of the cells we talk about
reside.
What is G1? - correct answer ✔✔This is where all cellular materials (excluding genetic material)
is duplicated.
What is the S phase? - correct answer ✔✔This is where DNA synthesis occurs. Note: Agents may
bind to DNA to stop DNA synthesis.
What is G2? - correct answer ✔✔Microtubule inhibitors stop making cell components needed
to separate. The cell is double-checking to ensure it is ready for replication.
What is the Dynamic Regulatory Barrier? - correct answer ✔✔The plasma membrane; it
changes to regulate imports and exports and helps maintain homeokinesis (maintaining the
intracellular environment)
1972 Singer & Nicolson - correct answer ✔✔Described the plasma membrane as a phospholipid
bilayer
What are the components of a phospholipid? - correct answer ✔✔Phosphate head attached to
a carbon glycerol attached to a fatty acid tail.
,What kinds of proteins (general then specific) allow for cell-cell interactions? - correct answer
✔✔Integrins; cadherins
Spacing between desmosomes; What kind of particle movement is shown in this instance? -
correct answer ✔✔Around a 20nm space (not tight enough for stopping molecules);
paracellular movement (between the cells)
What are tight junctions and what kind of movement? - correct answer ✔✔These cause a
blockage of the extracellular pathway. Transcellular movement (in through and out of the cell
past the tight junction.
Pre-gut closure - correct answer ✔✔Tight junctions aren't tight enough and allow a lot of
paracellular movement
What are gap junctions, what are their spacings, and where are they very important? - correct
answer ✔✔They are tunnel-like junctions between cells. They are around 2-4 nm between cells
(with 1.5nm channels) and are very important in intercalated disks in the heart in transferring
information through the cells
Diffusion vs osmosis - correct answer ✔✔Diffusion is the movement of solute to reach
equilibrium whereas osmosis is the movement of solvent across the plasma membrane (from
high-->low conc.)
What is a flux? - correct answer ✔✔The flow of a something across a membrane
Which ways can flux go? What is a net flux? - correct answer ✔✔Flux can go both directions,
just more heavily down the gradient. A net flux is the overall movement of molecules taking into
account the reverse flux.
, What four factors determine the rate of diffusion - correct answer ✔✔Kinetic
energy/temperature within the molecule, permeability of the membrane, concentration
gradient, difference in membrane potential (elec. charge)
Facilitated diffusion, why does this happen, and what molecules primarily do this? - correct
answer ✔✔Moving things down the gradient with help of an intermediate carrier protein. This
happens when molecules are not compatible with the membrane (polar molecules).
GLUT-4 - correct answer ✔✔A carrier responsible for facilitated glucose movement in cells --
sodium dependent in kidneys
What impacts facilitated diffusion - correct answer ✔✔Concentration gradient and the
abundance of carrier proteins
What helps set up polarity of the plasma membrane? - correct answer ✔✔The sodium-
potassium ATPase pump
Secondary active transpory - correct answer ✔✔This uses the energy in an ion gradient to move
a second solute (eg. Sodium moves down its concentration gradient and takes along glucose or
AAs up its gradient)
Other examples: SGLT 1&2
How does phagocytosis work? - correct answer ✔✔Bigger objects are taken into membrane-
bound vesicles that fuse to the lysosome within the cell
What are Kuppfer cells - correct answer ✔✔Cells in the liver that are modified macrophages
that engulf cellular debris
