VPHY 3100 Exam 1 questions and
answers graded A+
Simple diffusion - correct answer ✔✔non-carrier mediated "downhill" movement of some
molecules across a cell membrane, ex: gases (CO2, N2, O2) and ethanol
Osmosis - correct answer ✔✔net diffusion of water across a membrane, from regions of higher
water concentration to lower water concentration
In order for osmosis to occur... - correct answer ✔✔1. membrane must be selectively
permeable to water
2. concentration gradient must exist
3. solute must be osmotically active
Osmotically active - correct answer ✔✔membrane is nearly impermeable to solute
Osmotic pressure - correct answer ✔✔force needed to counteract osmosis, increased by an
increase in solute concentration
Molarity - correct answer ✔✔(M) - 1 mol solute/ 1 L solution
Molality - correct answer ✔✔(m) - 1 mol solute/ 1 kg solvent
Osmolality - correct answer ✔✔the total molality of the solution, the sum of the molalities of all
solutes present
,Tonicity - correct answer ✔✔the total concentration of solutes
Types of membrane transport proteins - correct answer ✔✔pumps, carriers, channels
Types of carriers - correct answer ✔✔uniporter, symporter, and antiporter
Passive transport - correct answer ✔✔facilitated diffusion, energetically downhill
ex: all channels and some uniporters
Active transport - correct answer ✔✔energetically uphill
2 categories of active transport - correct answer ✔✔1. primary active transport (all pumps)
2. secondary active transport (symporters and anti porters)
The sodium pump - correct answer ✔✔electrogenic pump that creates and maintains the
primary ionic gradient across the plasma membrane, for each ATP burned, 3 Na ions move out
of the cell and 2 K ions into the cell
Membrane potential - correct answer ✔✔unequal charge distribution (the inside of the cell is
more negative than the outside of the cell)
Resting membrane potential - correct answer ✔✔Vr = -60 to -80 mV
Vr is nearly equal to Ek due to the presence of... - correct answer ✔✔leaky K channels
Nerst Equation - correct answer ✔✔describes an electrochemical equilibrium state for a specific
ion, which is a balancing point between the electrical and chemical diffusional forces acting on
the ion
, K has a higher membrane potential--- - correct answer ✔✔inside the cell.
Na has a higher membrane potential--- - correct answer ✔✔outside the cell.
Cl has a higher membrane potential--- - correct answer ✔✔outside the cell.
Ca has a higher membrane potential--- - correct answer ✔✔outside the cell.
Chemical signals - correct answer ✔✔how cells communicate with one another
Types of receptor proteins - correct answer ✔✔1. channel linked (ligand gated) receptors
2. enzyme-linked receptors
3. G protein coupled receptors
4. intracellular receptors
Two divisions of the nervous system - correct answer ✔✔1. central nervous system (CNS)
2. peripheral nervous system (PNS)
2 cell types of the nervous system - correct answer ✔✔glia
neurons
CNS - correct answer ✔✔brain and spinal cord
PNS - correct answer ✔✔all nervous tissue outside of the CNS
answers graded A+
Simple diffusion - correct answer ✔✔non-carrier mediated "downhill" movement of some
molecules across a cell membrane, ex: gases (CO2, N2, O2) and ethanol
Osmosis - correct answer ✔✔net diffusion of water across a membrane, from regions of higher
water concentration to lower water concentration
In order for osmosis to occur... - correct answer ✔✔1. membrane must be selectively
permeable to water
2. concentration gradient must exist
3. solute must be osmotically active
Osmotically active - correct answer ✔✔membrane is nearly impermeable to solute
Osmotic pressure - correct answer ✔✔force needed to counteract osmosis, increased by an
increase in solute concentration
Molarity - correct answer ✔✔(M) - 1 mol solute/ 1 L solution
Molality - correct answer ✔✔(m) - 1 mol solute/ 1 kg solvent
Osmolality - correct answer ✔✔the total molality of the solution, the sum of the molalities of all
solutes present
,Tonicity - correct answer ✔✔the total concentration of solutes
Types of membrane transport proteins - correct answer ✔✔pumps, carriers, channels
Types of carriers - correct answer ✔✔uniporter, symporter, and antiporter
Passive transport - correct answer ✔✔facilitated diffusion, energetically downhill
ex: all channels and some uniporters
Active transport - correct answer ✔✔energetically uphill
2 categories of active transport - correct answer ✔✔1. primary active transport (all pumps)
2. secondary active transport (symporters and anti porters)
The sodium pump - correct answer ✔✔electrogenic pump that creates and maintains the
primary ionic gradient across the plasma membrane, for each ATP burned, 3 Na ions move out
of the cell and 2 K ions into the cell
Membrane potential - correct answer ✔✔unequal charge distribution (the inside of the cell is
more negative than the outside of the cell)
Resting membrane potential - correct answer ✔✔Vr = -60 to -80 mV
Vr is nearly equal to Ek due to the presence of... - correct answer ✔✔leaky K channels
Nerst Equation - correct answer ✔✔describes an electrochemical equilibrium state for a specific
ion, which is a balancing point between the electrical and chemical diffusional forces acting on
the ion
, K has a higher membrane potential--- - correct answer ✔✔inside the cell.
Na has a higher membrane potential--- - correct answer ✔✔outside the cell.
Cl has a higher membrane potential--- - correct answer ✔✔outside the cell.
Ca has a higher membrane potential--- - correct answer ✔✔outside the cell.
Chemical signals - correct answer ✔✔how cells communicate with one another
Types of receptor proteins - correct answer ✔✔1. channel linked (ligand gated) receptors
2. enzyme-linked receptors
3. G protein coupled receptors
4. intracellular receptors
Two divisions of the nervous system - correct answer ✔✔1. central nervous system (CNS)
2. peripheral nervous system (PNS)
2 cell types of the nervous system - correct answer ✔✔glia
neurons
CNS - correct answer ✔✔brain and spinal cord
PNS - correct answer ✔✔all nervous tissue outside of the CNS
