BIO 212 #3 Test Questions Answered Correctly Graded A+
Light that has shorter wavelengths contains more energy. Which of the following has the
highest energy?
a. Violet
b. Blue
c. Green
d. Red - Answers a. violet
By looking at the wavelengths associated with the electromagnetic spectrum, you will see that
violet light has a shorter wavelength and more energy than blue, green, or red light. One way to
help remember this is that UV light (ultraviolet) is what causes sunburn as well as possible DNA
damage that can result in skin cancer. Both of these are effects associated with higher energy
levels.
Which of the following correctly outlines the Z-Scheme?
a. Photosystem II - Electron Transport Chain (ATP) - Photosystem I - Ferredoxin (NADPH)
b. Photosystem I - Electron Transport Chain (ATP) - Photosystem II - Ferredoxin (NADPH)
c. Photosystem II - Electron Transport Chain (NADPH) - Photosystem I - Ferredoxin (ATP)
d. Photosystem I - Electron Transport Chain (NADPH) - Photosystem II - Ferredoxin (ATP) -
Answers a. Photosystem II - Electron Transport Chain (ATP) - Photosystem I - Ferredoxin
(NADPH)
,It's counterintuitive since Photosystem I was discovered before Photosystem II. However,
Photosystem II is the one that splits H2O to yield the electrons that flow through the electron
transport chain. One way to remember this is that water has 2 hydrogens that are released in
Photosystem II. This is where photosynthesis starts. Therefore, Photosystem II precedes
Photosystem I. There is a proton motive force generated by the excited electrons leaving
Photosystem II that is used to generate ATP via ATP synthase. This should sound familiar from
cellular respiration. Remember that ATP has less stored energy than NADPH. In order to
generate the higher energy NADPH, the electrons need another energy boost provided by
Photosystem I. Now these "boosted" electrons can be used by ferredoxin to produce NADPH.
What are the 3 phases of the Calvin Cycle?
a. Photosystem II - ETC - Photosystem I
b. Fixation - Reduction - Regeneration
c. Fixation - Oxidation - Regeneration
d. Fixation - Oxidation - Reduction - Answers b. Fixation - Reduction - Regeneration
Since the Calvin Cycle is a cycle, regenerating some reactants needs to be part of the process.
The outputs from the Calvin Cycle result in the formation of sugars. Where do the carbons come
from? The carbons are fixed, added to the sugars, using CO2 from the air. The formation of a
larger more complex molecule, a sugar, from smaller molecules, CO2, is energetically
unfavorable. Therefore energy needs to be added to the system. This energy is provided by ATP
and NADPH. If you recall that electrons are the energy currency in NADPH and that the energy in
the form of electrons is transferred to glyceraldehyde-3-phosphate (Think intermediate in sugar
production). By accepting electrons, negative charges, the glyceraldehyde-3-phosphate
becomes reduced. The process is fixation of carbon in CO2, transfer of electrons to an
intermediate compound (reduction), followed by regeneration of the starting components of the
cycle.
A G-protein is unable to bind GTP, what is the result?
,a. The G-protein can no longer function
b. The G-protein does not use GTP and will function normally
c. The G-protein can use both ADP and GDP and will function normally
d. The G-protein will always be "on," signaling actively - Answers a. The G-portine can no longer
function
G proteins are part of some types of signal transduction cascades that are involved in
transducing a signal from outside of the cell, an extracellular ligand, into the cell resulting in
changes inside of the cell. The active form of the G protein is when it is bound to GTP. Think
higher energy is active. GTP (triphosphate) has more energy than GDP (diphosphate). G proteins
require interaction with GTP to be active.
Which of the following cell surface receptors is necessary for a lipid-soluble signal?
a. Desmosome receptors
b. Receptor Tyrosine Kinases
c. None, the signal cannot enter the cell
d. None, the signal can pass through the membrane - Answers d. None, the signal can pass
through the membrane
Recall that hydrophobic molecules, things that like lipids and hate water, can often pass through
a lipid bilayer such as a cell membrane. Therefore, lipid soluble signals often pass through the
membrane.
Lipid-insoluble signals require what to achieve a response?
, a. Desmosomes
b. Signal transduction
c. Hormone receptors in the nucleus
d. Proteoglycans - Answers b. Signal transduction
Since the cell membrane is composed of a lipid bilayer, signals that are not soluble in lipids
cannot cross. Therefore, the signal on the outside of the cell needs to be transmitted or
transduced from the outside of the cell to the inside of the cell.
The light and dark reactions of photosynthesis are linked by high energy intermediates that take
energy from the light reactions and transfer it to the dark reactions. Which of the following
statements best describes what would happen to the processes of photosynthesis if a plant cell
was not able to utilize ATP and NADPH?
a. Light would not be used as the initial energy source
b. Water would be unable to split and no oxygen would form
c. The light reactions would not occur because the electron carriers are essential to its function
d. The dark reactions would not occur and no sugars would be produced - Answers d. The dark
reactions would not occur and no sugars would be produced
The dark reactions (Calvin Cycle) require energy from the high energy intermediates, NADPH
and ATP, to begin the energy-requiring reactions. The product of the dark reactions is stored
chemical energy in the form of sugars. If electron carriers are not present then the light
Light that has shorter wavelengths contains more energy. Which of the following has the
highest energy?
a. Violet
b. Blue
c. Green
d. Red - Answers a. violet
By looking at the wavelengths associated with the electromagnetic spectrum, you will see that
violet light has a shorter wavelength and more energy than blue, green, or red light. One way to
help remember this is that UV light (ultraviolet) is what causes sunburn as well as possible DNA
damage that can result in skin cancer. Both of these are effects associated with higher energy
levels.
Which of the following correctly outlines the Z-Scheme?
a. Photosystem II - Electron Transport Chain (ATP) - Photosystem I - Ferredoxin (NADPH)
b. Photosystem I - Electron Transport Chain (ATP) - Photosystem II - Ferredoxin (NADPH)
c. Photosystem II - Electron Transport Chain (NADPH) - Photosystem I - Ferredoxin (ATP)
d. Photosystem I - Electron Transport Chain (NADPH) - Photosystem II - Ferredoxin (ATP) -
Answers a. Photosystem II - Electron Transport Chain (ATP) - Photosystem I - Ferredoxin
(NADPH)
,It's counterintuitive since Photosystem I was discovered before Photosystem II. However,
Photosystem II is the one that splits H2O to yield the electrons that flow through the electron
transport chain. One way to remember this is that water has 2 hydrogens that are released in
Photosystem II. This is where photosynthesis starts. Therefore, Photosystem II precedes
Photosystem I. There is a proton motive force generated by the excited electrons leaving
Photosystem II that is used to generate ATP via ATP synthase. This should sound familiar from
cellular respiration. Remember that ATP has less stored energy than NADPH. In order to
generate the higher energy NADPH, the electrons need another energy boost provided by
Photosystem I. Now these "boosted" electrons can be used by ferredoxin to produce NADPH.
What are the 3 phases of the Calvin Cycle?
a. Photosystem II - ETC - Photosystem I
b. Fixation - Reduction - Regeneration
c. Fixation - Oxidation - Regeneration
d. Fixation - Oxidation - Reduction - Answers b. Fixation - Reduction - Regeneration
Since the Calvin Cycle is a cycle, regenerating some reactants needs to be part of the process.
The outputs from the Calvin Cycle result in the formation of sugars. Where do the carbons come
from? The carbons are fixed, added to the sugars, using CO2 from the air. The formation of a
larger more complex molecule, a sugar, from smaller molecules, CO2, is energetically
unfavorable. Therefore energy needs to be added to the system. This energy is provided by ATP
and NADPH. If you recall that electrons are the energy currency in NADPH and that the energy in
the form of electrons is transferred to glyceraldehyde-3-phosphate (Think intermediate in sugar
production). By accepting electrons, negative charges, the glyceraldehyde-3-phosphate
becomes reduced. The process is fixation of carbon in CO2, transfer of electrons to an
intermediate compound (reduction), followed by regeneration of the starting components of the
cycle.
A G-protein is unable to bind GTP, what is the result?
,a. The G-protein can no longer function
b. The G-protein does not use GTP and will function normally
c. The G-protein can use both ADP and GDP and will function normally
d. The G-protein will always be "on," signaling actively - Answers a. The G-portine can no longer
function
G proteins are part of some types of signal transduction cascades that are involved in
transducing a signal from outside of the cell, an extracellular ligand, into the cell resulting in
changes inside of the cell. The active form of the G protein is when it is bound to GTP. Think
higher energy is active. GTP (triphosphate) has more energy than GDP (diphosphate). G proteins
require interaction with GTP to be active.
Which of the following cell surface receptors is necessary for a lipid-soluble signal?
a. Desmosome receptors
b. Receptor Tyrosine Kinases
c. None, the signal cannot enter the cell
d. None, the signal can pass through the membrane - Answers d. None, the signal can pass
through the membrane
Recall that hydrophobic molecules, things that like lipids and hate water, can often pass through
a lipid bilayer such as a cell membrane. Therefore, lipid soluble signals often pass through the
membrane.
Lipid-insoluble signals require what to achieve a response?
, a. Desmosomes
b. Signal transduction
c. Hormone receptors in the nucleus
d. Proteoglycans - Answers b. Signal transduction
Since the cell membrane is composed of a lipid bilayer, signals that are not soluble in lipids
cannot cross. Therefore, the signal on the outside of the cell needs to be transmitted or
transduced from the outside of the cell to the inside of the cell.
The light and dark reactions of photosynthesis are linked by high energy intermediates that take
energy from the light reactions and transfer it to the dark reactions. Which of the following
statements best describes what would happen to the processes of photosynthesis if a plant cell
was not able to utilize ATP and NADPH?
a. Light would not be used as the initial energy source
b. Water would be unable to split and no oxygen would form
c. The light reactions would not occur because the electron carriers are essential to its function
d. The dark reactions would not occur and no sugars would be produced - Answers d. The dark
reactions would not occur and no sugars would be produced
The dark reactions (Calvin Cycle) require energy from the high energy intermediates, NADPH
and ATP, to begin the energy-requiring reactions. The product of the dark reactions is stored
chemical energy in the form of sugars. If electron carriers are not present then the light
