Biology 212 Exam 1 Verified Questions And Answers
How does one determine the number of covalent bonds an element will likely form? ANS The
number of valence electrons
What properties make water an excellent solvent? ANS Polarity, molecular shape, hydrogen bonding
An amphipathic molecule contains what? ANS Both hydrophilic and hydrophobic zones
We find an unknown liquid that is non-polar. When it is placed in water, what can we expect to happen?
ANS The unknown liquid will not dissolve
A newly discovered organelle breaks apart a protein and puts it back together. Which processes are used?
ANS Hydrolysis and dehydration reactions
Pasteur used two types of flasks in his famous experiment: an open-top and a swan-necked flask. What
was the experimental variable? ANS Access to microbes in the air
What is responsible for lipid bilayer formation in water with phospholipids? ANS Amphipathic
properties of phospholipids
What type of transport mechanism could be used to move a molecule of glucose across a membrane
against a concentration gradient? ANS Active transport
As lipids become less saturated, we expect membrane permeability to ANS Increase
Peripheral membrane proteins differ from transmembrane proteins in that they ANS Do not cross the
lipid bilayer
A toxin is known to disrupt actin filaments and microtubules. Which cell structure and function are most
affected? ANS Cytoskeleton - cell movements
, Which of the following can be found in prokaryotic cells? ANS Ribosomes
A pure phospholipid membrane separates two chambers of water. Oxygen molecules and potassium ions
are added to the water in Chamber #1. You return to the chamber after a few days and notice that
everything that was added is now present in Chamber #2. What is the relative permeability of these
molecules across this lipid bilayer from most permeable to least permeable? ANS Oxygen, water,
potassium
Chamber A is separated from Chamber B by a phospholipid membrane that contains only water
permeable channels. If Chamber A contains 0.4 M sodium in solution and chamber B contains 0.1 M
sodium in solution, in which direction will the water flow and what would equilibrium be? ANS
Water will move from Chamber A to Chamber B, equilibrium would be 0.25 M
A cell containing a phospholipid membrane that typically transports sodium using an ATP-driven sodium
pump is prevented from making additional ATP. Which of the following statements is true regarding the
cell? ANS The pump still stop pumping sodium against the concentration gradient
Consider a lipid membrane consisting of fatty acids with two double bonds. What would you expect of
the resulting membrane? ANS The membrane has fluidity
A cell is moved from a warm incubator to a cold lab bench. Which of the following adjustments could the
cell make to keep membrane fluidity the same? ANS Increase proportion of unsaturated hydrocarbon
tails in the membrane phospholipids
While traveling the world, you have encountered a new insect that lives in the extreme heat of the African
desert. When you bring the insect back to Iowa it begins to die, likely because it is unable to maintain
membrane homeostasis. What would increase this insect's ability to cope with this temperature change?
ANS Increase the amount of unsaturated fatty acids
A Pulse-Chase experiment using radioactive amino acids is completed to track the passage of proteins in
pancreatic cells, where we know proteins are commonly secreted from the cells. However, after the
experiment is concluded, no proteins are being secreted. However, protein is being made in the cell.
Which of the following organelles is not likely the source of dysfunction in the cell? ANS Nucleus
A phospholipid membrane bilayer contains multiple integral membrane proteins, meaning that the
proteins span the length of the membrane. These proteins act as channels, allowing for the passage of
How does one determine the number of covalent bonds an element will likely form? ANS The
number of valence electrons
What properties make water an excellent solvent? ANS Polarity, molecular shape, hydrogen bonding
An amphipathic molecule contains what? ANS Both hydrophilic and hydrophobic zones
We find an unknown liquid that is non-polar. When it is placed in water, what can we expect to happen?
ANS The unknown liquid will not dissolve
A newly discovered organelle breaks apart a protein and puts it back together. Which processes are used?
ANS Hydrolysis and dehydration reactions
Pasteur used two types of flasks in his famous experiment: an open-top and a swan-necked flask. What
was the experimental variable? ANS Access to microbes in the air
What is responsible for lipid bilayer formation in water with phospholipids? ANS Amphipathic
properties of phospholipids
What type of transport mechanism could be used to move a molecule of glucose across a membrane
against a concentration gradient? ANS Active transport
As lipids become less saturated, we expect membrane permeability to ANS Increase
Peripheral membrane proteins differ from transmembrane proteins in that they ANS Do not cross the
lipid bilayer
A toxin is known to disrupt actin filaments and microtubules. Which cell structure and function are most
affected? ANS Cytoskeleton - cell movements
, Which of the following can be found in prokaryotic cells? ANS Ribosomes
A pure phospholipid membrane separates two chambers of water. Oxygen molecules and potassium ions
are added to the water in Chamber #1. You return to the chamber after a few days and notice that
everything that was added is now present in Chamber #2. What is the relative permeability of these
molecules across this lipid bilayer from most permeable to least permeable? ANS Oxygen, water,
potassium
Chamber A is separated from Chamber B by a phospholipid membrane that contains only water
permeable channels. If Chamber A contains 0.4 M sodium in solution and chamber B contains 0.1 M
sodium in solution, in which direction will the water flow and what would equilibrium be? ANS
Water will move from Chamber A to Chamber B, equilibrium would be 0.25 M
A cell containing a phospholipid membrane that typically transports sodium using an ATP-driven sodium
pump is prevented from making additional ATP. Which of the following statements is true regarding the
cell? ANS The pump still stop pumping sodium against the concentration gradient
Consider a lipid membrane consisting of fatty acids with two double bonds. What would you expect of
the resulting membrane? ANS The membrane has fluidity
A cell is moved from a warm incubator to a cold lab bench. Which of the following adjustments could the
cell make to keep membrane fluidity the same? ANS Increase proportion of unsaturated hydrocarbon
tails in the membrane phospholipids
While traveling the world, you have encountered a new insect that lives in the extreme heat of the African
desert. When you bring the insect back to Iowa it begins to die, likely because it is unable to maintain
membrane homeostasis. What would increase this insect's ability to cope with this temperature change?
ANS Increase the amount of unsaturated fatty acids
A Pulse-Chase experiment using radioactive amino acids is completed to track the passage of proteins in
pancreatic cells, where we know proteins are commonly secreted from the cells. However, after the
experiment is concluded, no proteins are being secreted. However, protein is being made in the cell.
Which of the following organelles is not likely the source of dysfunction in the cell? ANS Nucleus
A phospholipid membrane bilayer contains multiple integral membrane proteins, meaning that the
proteins span the length of the membrane. These proteins act as channels, allowing for the passage of
