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Question is based on the following passage.
This passage is adapted from Daniel Chamovitz, What a Plant Knows: A Field Guide to the Senses. ©2012 by Daniel Chamovitz.
The Venus flytrap [Dionaea muscipula] needs to
know when an ideal meal is crawling across its leaves.
Closing its trap requires a huge expense of energy,
and reopening the trap can take several hours, so
5 Dionaea only wants to spring closed when it’s sure
that the dawdling insect visiting its surface is large
enough to be worth its time. The large black hairs on
their lobes allow the Venus flytraps to literally feel
their prey, and they act as triggers that spring the
10 trap closed when the proper prey makes its way
across the trap. If the insect touches just one hair, the
trap will not spring shut; but a large enough bug will
likely touch two hairs within about twenty seconds,
and that signal springs the Venus flytrap into action.
15 We can look at this system as analogous to
short-term memory. First, the flytrap encodes the
information (forms the memory) that something (it
doesn’t know what) has touched one of its hairs.
Then it stores this information for a number of
20 seconds (retains the memory) and finally retrieves
this information (recalls the memory) once a second
hair is touched. If a small ant takes a while to get
from one hair to the next, the trap will have forgotten
the first touch by the time the ant brushes up against
25 the next hair. In other words, it loses the storage of
the information, doesn’t close, and the ant
happily meanders on. How does the plant encode
and store the information from the unassuming
bug’s encounter with the first hair? How does it
30 remember the first touch in order to react upon the
second?
Scientists have been puzzled by these questions
ever since John Burdon-Sanderson’s early report on
the physiology of the Venus flytrap in 1882. A
35 century later, Dieter Hodick and Andreas Sievers at
the University of Bonn in Germany proposed that
the flytrap stored information regarding how many
hairs have been touched in the electric charge of its
leaf. Their model is quite elegant in its simplicity.
40 In their studies, they discovered that touching a
trigger hair on the Venus flytrap causes an electric
action potential [a temporary reversal in the
electrical polarity of a cell membrane] that
induces calcium channels to open in the trap (this
45 coupling of action potentials and the opening of
calcium channels is similar to the processes that
occur during communication between human
neurons), thus causing a rapid increase in the
concentration of calcium ions.
50 They proposed that the trap requires a relatively
high concentration of calcium in order to close
and that a single action potential from just one
trigger hair being touched does not reach this level.
Therefore, a second hair needs to be stimulated to
55 push the calcium concentration over this threshold
and spring the trap. The encoding of the information
requires maintaining a high enough level of calcium
so that a second increase (triggered by touching the
second hair) pushes the total concentration of
60 calcium over the threshold. As the calcium ion
concentrations dissipate over time, if the second
touch and potential don’t happen quickly, the final
concentration after the second trigger won’t be high
enough to close the trap, and the memory is lost.
65 Subsequent research supports this model.
Alexander Volkov and his colleagues at Oakwood
University in Alabama first demonstrated that it is
indeed electricity that causes the Venus flytrap to
close. To test the model they rigged up very fine
70 electrodes and applied an electrical current to the
open lobes of the trap. This made the trap close
without any direct touch to its trigger hairs (while
they didn’t measure calcium levels, the current
likely led to increases). When they modified this
75 experiment by altering the amount of electrical
current, Volkov could determine the exact electrical
charge needed for the trap to close. As long as
fourteen microcoulombs—a tiny bit more than the
static electricity generated by rubbing two balloons
80 together—flowed between the two electrodes, the
trap closed. This could come as one large burst or as
a series of smaller charges within twenty seconds. If it
took longer than twenty seconds to accumulate the
total charge, the trap would remain open.
This passage is adapted from Daniel Chamovitz, What a Plant Knows: A Field Guide to the Senses. ©2012 by Daniel Chamovitz.
The Venus flytrap [Dionaea muscipula] needs to
know when an ideal meal is crawling across its leaves.
Closing its trap requires a huge expense of energy,
and reopening the trap can take several hours, so
5 Dionaea only wants to spring closed when it’s sure
that the dawdling insect visiting its surface is large
enough to be worth its time. The large black hairs on
their lobes allow the Venus flytraps to literally feel
their prey, and they act as triggers that spring the
10 trap closed when the proper prey makes its way
across the trap. If the insect touches just one hair, the
trap will not spring shut; but a large enough bug will
likely touch two hairs within about twenty seconds,
and that signal springs the Venus flytrap into action.
15 We can look at this system as analogous to
short-term memory. First, the flytrap encodes the
information (forms the memory) that something (it
doesn’t know what) has touched one of its hairs.
Then it stores this information for a number of
20 seconds (retains the memory) and finally retrieves
this information (recalls the memory) once a second
hair is touched. If a small ant takes a while to get
from one hair to the next, the trap will have forgotten
the first touch by the time the ant brushes up against
25 the next hair. In other words, it loses the storage of
the information, doesn’t close, and the ant
happily meanders on. How does the plant encode
and store the information from the unassuming
bug’s encounter with the first hair? How does it
30 remember the first touch in order to react upon the
second?
Scientists have been puzzled by these questions
ever since John Burdon-Sanderson’s early report on
the physiology of the Venus flytrap in 1882. A
35 century later, Dieter Hodick and Andreas Sievers at
the University of Bonn in Germany proposed that
the flytrap stored information regarding how many
hairs have been touched in the electric charge of its
leaf. Their model is quite elegant in its simplicity.
40 In their studies, they discovered that touching a
trigger hair on the Venus flytrap causes an electric
action potential [a temporary reversal in the
electrical polarity of a cell membrane] that
induces calcium channels to open in the trap (this
45 coupling of action potentials and the opening of
calcium channels is similar to the processes that
occur during communication between human
neurons), thus causing a rapid increase in the
concentration of calcium ions.
50 They proposed that the trap requires a relatively
high concentration of calcium in order to close
and that a single action potential from just one
trigger hair being touched does not reach this level.
Therefore, a second hair needs to be stimulated to
55 push the calcium concentration over this threshold
and spring the trap. The encoding of the information
requires maintaining a high enough level of calcium
so that a second increase (triggered by touching the
second hair) pushes the total concentration of
60 calcium over the threshold. As the calcium ion
concentrations dissipate over time, if the second
touch and potential don’t happen quickly, the final
concentration after the second trigger won’t be high
enough to close the trap, and the memory is lost.
65 Subsequent research supports this model.
Alexander Volkov and his colleagues at Oakwood
University in Alabama first demonstrated that it is
indeed electricity that causes the Venus flytrap to
close. To test the model they rigged up very fine
70 electrodes and applied an electrical current to the
open lobes of the trap. This made the trap close
without any direct touch to its trigger hairs (while
they didn’t measure calcium levels, the current
likely led to increases). When they modified this
75 experiment by altering the amount of electrical
current, Volkov could determine the exact electrical
charge needed for the trap to close. As long as
fourteen microcoulombs—a tiny bit more than the
static electricity generated by rubbing two balloons
80 together—flowed between the two electrodes, the
trap closed. This could come as one large burst or as
a series of smaller charges within twenty seconds. If it
took longer than twenty seconds to accumulate the
total charge, the trap would remain open.
Q. The primary purpose of the passage is to
- a)discuss findings that offer a scientificexplanation for the Venus flytrap’s closingaction.
- b)present research that suggests that the Venusflytrap’s predatory behavior is both complex andunique among plants.
- c)identify the process by which the Venus flytrap’sclosing action has evolved.
- d)provide a brief overview of the Venus flytrap andits predatory behavior.
Correct answer is option 'A'. Can you explain this answer?
Most Upvoted Answer
Question is based on the following passage.This passage is adapted fro...
Choice A is the best answer. The first two paragraphs of the passage describe the physical process by which the Venus flytrap closes its trap but also note certain long-standing questions about that process: “How does the plant encode and store the information from the unassuming bug’s encounter with the first hair? How does it remember the first touch in order to react upon the second?” The passage then answers those questions by discussing, in the third and fourth paragraphs, a study conducted by Dieter Hodick and Andreas Sievers that identified the physiological means behind the closing of the Venus flytrap’s trap and, in the last paragraph, a study conducted by Alexander Volkov that confirmed and built on Hodick and Sievers’s findings. The primary purpose of the passage can therefore be seen as discussing scientific findings that explain how the Venus flytrap closes its trap. Choice B is incorrect because the passage doesn’t discuss the Venus flytrap’s ability to close its trap in the context of the abilities of other plants. Choice C is incorrect because the passage discusses how the closing action operates but not how it has evolved. Choice D is incorrect because the passage doesn’t provide an overview of the Venus flytrap and its predatory behavior; it merely notes in passing that the closing action has a predatory function.
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Question is based on the following passage.This passage is adapted from Daniel Chamovitz, What a Plant Knows: A Field Guide to the Senses. ©2012 by Daniel Chamovitz.The Venus flytrap [Dionaea muscipula] needs toknow when an ideal meal is crawling across its leaves.Closing its trap requires a huge expense of energy,and reopening the trap can take several hours, so5 Dionaea only wants to spring closed when it’s surethat the dawdling insect visiting its surface is largeenough to be worth its time. The large black hairs ontheir lobes allow the Venus flytraps to literally feeltheir prey, and they act as triggers that spring the10 trap closed when the proper prey makes its wayacross the trap. If the insect touches just one hair, thetrap will not spring shut; but a large enough bug willlikely touch two hairs within about twenty seconds,and that signal springs the Venus flytrap into action.15 We can look at this system as analogous toshort-term memory. First, the flytrap encodes theinformation (forms the memory) that something (itdoesn’t know what) has touched one of its hairs.Then it stores this information for a number of20seconds (retains the memory) and finally retrievesthis information (recalls the memory) once a secondhair is touched. If a small ant takes a while to getfrom one hair to the next, the trap will have forgottenthe first touch by the time the ant brushes up against25the next hair. In other words, it loses the storage ofthe information, doesn’t close, and the anthappily meanders on. How does the plant encodeand store the information from the unassumingbug’s encounter with the first hair? How does it30 remember the first touch in order to react upon thesecond?Scientists have been puzzled by these questionsever since John Burdon-Sanderson’s early report onthe physiology of the Venus flytrap in 1882. A35 century later, Dieter Hodick and Andreas Sievers atthe University of Bonn in Germany proposed thatthe flytrap stored information regarding how manyhairs have been touched in the electric charge of itsleaf. Their model is quite elegant in its simplicity.40In their studies, they discovered that touching atrigger hair on the Venus flytrap causes an electricaction potential [a temporary reversal in theelectrical polarity of a cell membrane] thatinduces calcium channels to open in the trap (this45coupling of action potentials and the opening ofcalcium channels is similar to the processes thatoccur during communication between humanneurons), thus causing a rapid increase in theconcentration of calcium ions.50They proposed that the trap requires a relativelyhigh concentration of calcium in order to closeand that a single action potential from just onetrigger hair being touched does not reach this level.Therefore, a second hair needs to be stimulated to55push the calcium concentration over this thresholdand spring the trap. The encoding of the informationrequires maintaining a high enough level of calciumso that a second increase (triggered by touching thesecond hair) pushes the total concentration of60calcium over the threshold. As the calcium ionconcentrations dissipate over time, if the secondtouch and potential don’t happen quickly, the finalconcentration after the second trigger won’t be highenough to close the trap, and the memory is lost.65Subsequent research supports this model.Alexander Volkov and his colleagues at OakwoodUniversity in Alabama first demonstrated that it isindeed electricity that causes the Venus flytrap toclose. To test the model they rigged up very fine70electrodes and applied an electrical current to theopen lobes of the trap. This made the trap closewithout any direct touch to its trigger hairs (whilethey didn’t measure calcium levels, the currentlikely led to increases). When they modified this75experiment by altering the amount of electricalcurrent, Volkov could determine the exact electricalcharge needed for the trap to close. As long asfourteen microcoulombs—a tiny bit more than thestatic electricity generated by rubbing two balloons80together—flowed between the two electrodes, thetrap closed. This could come as one large burst or asa series of smaller charges within twenty seconds. If ittook longer than twenty seconds to accumulate thetotal charge, the trap would remain open.Q. The primary purpose of the passage is toa)discuss findings that offer a scientificexplanation for the Venus flytrap’s closingaction.b)present research that suggests that the Venusflytrap’s predatory behavior is both complex andunique among plants.c)identify the process by which the Venus flytrap’sclosing action has evolved.d)provide a brief overview of the Venus flytrap andits predatory behavior.Correct answer is option 'A'. Can you explain this answer?
Question Description
Question is based on the following passage.This passage is adapted from Daniel Chamovitz, What a Plant Knows: A Field Guide to the Senses. ©2012 by Daniel Chamovitz.The Venus flytrap [Dionaea muscipula] needs toknow when an ideal meal is crawling across its leaves.Closing its trap requires a huge expense of energy,and reopening the trap can take several hours, so5 Dionaea only wants to spring closed when it’s surethat the dawdling insect visiting its surface is largeenough to be worth its time. The large black hairs ontheir lobes allow the Venus flytraps to literally feeltheir prey, and they act as triggers that spring the10 trap closed when the proper prey makes its wayacross the trap. If the insect touches just one hair, thetrap will not spring shut; but a large enough bug willlikely touch two hairs within about twenty seconds,and that signal springs the Venus flytrap into action.15 We can look at this system as analogous toshort-term memory. First, the flytrap encodes theinformation (forms the memory) that something (itdoesn’t know what) has touched one of its hairs.Then it stores this information for a number of20seconds (retains the memory) and finally retrievesthis information (recalls the memory) once a secondhair is touched. If a small ant takes a while to getfrom one hair to the next, the trap will have forgottenthe first touch by the time the ant brushes up against25the next hair. In other words, it loses the storage ofthe information, doesn’t close, and the anthappily meanders on. How does the plant encodeand store the information from the unassumingbug’s encounter with the first hair? How does it30 remember the first touch in order to react upon thesecond?Scientists have been puzzled by these questionsever since John Burdon-Sanderson’s early report onthe physiology of the Venus flytrap in 1882. A35 century later, Dieter Hodick and Andreas Sievers atthe University of Bonn in Germany proposed thatthe flytrap stored information regarding how manyhairs have been touched in the electric charge of itsleaf. Their model is quite elegant in its simplicity.40In their studies, they discovered that touching atrigger hair on the Venus flytrap causes an electricaction potential [a temporary reversal in theelectrical polarity of a cell membrane] thatinduces calcium channels to open in the trap (this45coupling of action potentials and the opening ofcalcium channels is similar to the processes thatoccur during communication between humanneurons), thus causing a rapid increase in theconcentration of calcium ions.50They proposed that the trap requires a relativelyhigh concentration of calcium in order to closeand that a single action potential from just onetrigger hair being touched does not reach this level.Therefore, a second hair needs to be stimulated to55push the calcium concentration over this thresholdand spring the trap. The encoding of the informationrequires maintaining a high enough level of calciumso that a second increase (triggered by touching thesecond hair) pushes the total concentration of60calcium over the threshold. As the calcium ionconcentrations dissipate over time, if the secondtouch and potential don’t happen quickly, the finalconcentration after the second trigger won’t be highenough to close the trap, and the memory is lost.65Subsequent research supports this model.Alexander Volkov and his colleagues at OakwoodUniversity in Alabama first demonstrated that it isindeed electricity that causes the Venus flytrap toclose. To test the model they rigged up very fine70electrodes and applied an electrical current to theopen lobes of the trap. This made the trap closewithout any direct touch to its trigger hairs (whilethey didn’t measure calcium levels, the currentlikely led to increases). When they modified this75experiment by altering the amount of electricalcurrent, Volkov could determine the exact electricalcharge needed for the trap to close. As long asfourteen microcoulombs—a tiny bit more than thestatic electricity generated by rubbing two balloons80together—flowed between the two electrodes, thetrap closed. This could come as one large burst or asa series of smaller charges within twenty seconds. If ittook longer than twenty seconds to accumulate thetotal charge, the trap would remain open.Q. The primary purpose of the passage is toa)discuss findings that offer a scientificexplanation for the Venus flytrap’s closingaction.b)present research that suggests that the Venusflytrap’s predatory behavior is both complex andunique among plants.c)identify the process by which the Venus flytrap’sclosing action has evolved.d)provide a brief overview of the Venus flytrap andits predatory behavior.Correct answer is option 'A'. Can you explain this answer? for SAT 2025 is part of SAT preparation. The Question and answers have been prepared according to the SAT exam syllabus. Information about Question is based on the following passage.This passage is adapted from Daniel Chamovitz, What a Plant Knows: A Field Guide to the Senses. ©2012 by Daniel Chamovitz.The Venus flytrap [Dionaea muscipula] needs toknow when an ideal meal is crawling across its leaves.Closing its trap requires a huge expense of energy,and reopening the trap can take several hours, so5 Dionaea only wants to spring closed when it’s surethat the dawdling insect visiting its surface is largeenough to be worth its time. The large black hairs ontheir lobes allow the Venus flytraps to literally feeltheir prey, and they act as triggers that spring the10 trap closed when the proper prey makes its wayacross the trap. If the insect touches just one hair, thetrap will not spring shut; but a large enough bug willlikely touch two hairs within about twenty seconds,and that signal springs the Venus flytrap into action.15 We can look at this system as analogous toshort-term memory. First, the flytrap encodes theinformation (forms the memory) that something (itdoesn’t know what) has touched one of its hairs.Then it stores this information for a number of20seconds (retains the memory) and finally retrievesthis information (recalls the memory) once a secondhair is touched. If a small ant takes a while to getfrom one hair to the next, the trap will have forgottenthe first touch by the time the ant brushes up against25the next hair. In other words, it loses the storage ofthe information, doesn’t close, and the anthappily meanders on. How does the plant encodeand store the information from the unassumingbug’s encounter with the first hair? How does it30 remember the first touch in order to react upon thesecond?Scientists have been puzzled by these questionsever since John Burdon-Sanderson’s early report onthe physiology of the Venus flytrap in 1882. A35 century later, Dieter Hodick and Andreas Sievers atthe University of Bonn in Germany proposed thatthe flytrap stored information regarding how manyhairs have been touched in the electric charge of itsleaf. Their model is quite elegant in its simplicity.40In their studies, they discovered that touching atrigger hair on the Venus flytrap causes an electricaction potential [a temporary reversal in theelectrical polarity of a cell membrane] thatinduces calcium channels to open in the trap (this45coupling of action potentials and the opening ofcalcium channels is similar to the processes thatoccur during communication between humanneurons), thus causing a rapid increase in theconcentration of calcium ions.50They proposed that the trap requires a relativelyhigh concentration of calcium in order to closeand that a single action potential from just onetrigger hair being touched does not reach this level.Therefore, a second hair needs to be stimulated to55push the calcium concentration over this thresholdand spring the trap. The encoding of the informationrequires maintaining a high enough level of calciumso that a second increase (triggered by touching thesecond hair) pushes the total concentration of60calcium over the threshold. As the calcium ionconcentrations dissipate over time, if the secondtouch and potential don’t happen quickly, the finalconcentration after the second trigger won’t be highenough to close the trap, and the memory is lost.65Subsequent research supports this model.Alexander Volkov and his colleagues at OakwoodUniversity in Alabama first demonstrated that it isindeed electricity that causes the Venus flytrap toclose. To test the model they rigged up very fine70electrodes and applied an electrical current to theopen lobes of the trap. This made the trap closewithout any direct touch to its trigger hairs (whilethey didn’t measure calcium levels, the currentlikely led to increases). When they modified this75experiment by altering the amount of electricalcurrent, Volkov could determine the exact electricalcharge needed for the trap to close. As long asfourteen microcoulombs—a tiny bit more than thestatic electricity generated by rubbing two balloons80together—flowed between the two electrodes, thetrap closed. This could come as one large burst or asa series of smaller charges within twenty seconds. If ittook longer than twenty seconds to accumulate thetotal charge, the trap would remain open.Q. The primary purpose of the passage is toa)discuss findings that offer a scientificexplanation for the Venus flytrap’s closingaction.b)present research that suggests that the Venusflytrap’s predatory behavior is both complex andunique among plants.c)identify the process by which the Venus flytrap’sclosing action has evolved.d)provide a brief overview of the Venus flytrap andits predatory behavior.Correct answer is option 'A'. Can you explain this answer? covers all topics & solutions for SAT 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Question is based on the following passage.This passage is adapted from Daniel Chamovitz, What a Plant Knows: A Field Guide to the Senses. ©2012 by Daniel Chamovitz.The Venus flytrap [Dionaea muscipula] needs toknow when an ideal meal is crawling across its leaves.Closing its trap requires a huge expense of energy,and reopening the trap can take several hours, so5 Dionaea only wants to spring closed when it’s surethat the dawdling insect visiting its surface is largeenough to be worth its time. The large black hairs ontheir lobes allow the Venus flytraps to literally feeltheir prey, and they act as triggers that spring the10 trap closed when the proper prey makes its wayacross the trap. If the insect touches just one hair, thetrap will not spring shut; but a large enough bug willlikely touch two hairs within about twenty seconds,and that signal springs the Venus flytrap into action.15 We can look at this system as analogous toshort-term memory. First, the flytrap encodes theinformation (forms the memory) that something (itdoesn’t know what) has touched one of its hairs.Then it stores this information for a number of20seconds (retains the memory) and finally retrievesthis information (recalls the memory) once a secondhair is touched. If a small ant takes a while to getfrom one hair to the next, the trap will have forgottenthe first touch by the time the ant brushes up against25the next hair. In other words, it loses the storage ofthe information, doesn’t close, and the anthappily meanders on. How does the plant encodeand store the information from the unassumingbug’s encounter with the first hair? How does it30 remember the first touch in order to react upon thesecond?Scientists have been puzzled by these questionsever since John Burdon-Sanderson’s early report onthe physiology of the Venus flytrap in 1882. A35 century later, Dieter Hodick and Andreas Sievers atthe University of Bonn in Germany proposed thatthe flytrap stored information regarding how manyhairs have been touched in the electric charge of itsleaf. Their model is quite elegant in its simplicity.40In their studies, they discovered that touching atrigger hair on the Venus flytrap causes an electricaction potential [a temporary reversal in theelectrical polarity of a cell membrane] thatinduces calcium channels to open in the trap (this45coupling of action potentials and the opening ofcalcium channels is similar to the processes thatoccur during communication between humanneurons), thus causing a rapid increase in theconcentration of calcium ions.50They proposed that the trap requires a relativelyhigh concentration of calcium in order to closeand that a single action potential from just onetrigger hair being touched does not reach this level.Therefore, a second hair needs to be stimulated to55push the calcium concentration over this thresholdand spring the trap. The encoding of the informationrequires maintaining a high enough level of calciumso that a second increase (triggered by touching thesecond hair) pushes the total concentration of60calcium over the threshold. As the calcium ionconcentrations dissipate over time, if the secondtouch and potential don’t happen quickly, the finalconcentration after the second trigger won’t be highenough to close the trap, and the memory is lost.65Subsequent research supports this model.Alexander Volkov and his colleagues at OakwoodUniversity in Alabama first demonstrated that it isindeed electricity that causes the Venus flytrap toclose. To test the model they rigged up very fine70electrodes and applied an electrical current to theopen lobes of the trap. This made the trap closewithout any direct touch to its trigger hairs (whilethey didn’t measure calcium levels, the currentlikely led to increases). When they modified this75experiment by altering the amount of electricalcurrent, Volkov could determine the exact electricalcharge needed for the trap to close. As long asfourteen microcoulombs—a tiny bit more than thestatic electricity generated by rubbing two balloons80together—flowed between the two electrodes, thetrap closed. This could come as one large burst or asa series of smaller charges within twenty seconds. If ittook longer than twenty seconds to accumulate thetotal charge, the trap would remain open.Q. The primary purpose of the passage is toa)discuss findings that offer a scientificexplanation for the Venus flytrap’s closingaction.b)present research that suggests that the Venusflytrap’s predatory behavior is both complex andunique among plants.c)identify the process by which the Venus flytrap’sclosing action has evolved.d)provide a brief overview of the Venus flytrap andits predatory behavior.Correct answer is option 'A'. Can you explain this answer?.
Question is based on the following passage.This passage is adapted from Daniel Chamovitz, What a Plant Knows: A Field Guide to the Senses. ©2012 by Daniel Chamovitz.The Venus flytrap [Dionaea muscipula] needs toknow when an ideal meal is crawling across its leaves.Closing its trap requires a huge expense of energy,and reopening the trap can take several hours, so5 Dionaea only wants to spring closed when it’s surethat the dawdling insect visiting its surface is largeenough to be worth its time. The large black hairs ontheir lobes allow the Venus flytraps to literally feeltheir prey, and they act as triggers that spring the10 trap closed when the proper prey makes its wayacross the trap. If the insect touches just one hair, thetrap will not spring shut; but a large enough bug willlikely touch two hairs within about twenty seconds,and that signal springs the Venus flytrap into action.15 We can look at this system as analogous toshort-term memory. First, the flytrap encodes theinformation (forms the memory) that something (itdoesn’t know what) has touched one of its hairs.Then it stores this information for a number of20seconds (retains the memory) and finally retrievesthis information (recalls the memory) once a secondhair is touched. If a small ant takes a while to getfrom one hair to the next, the trap will have forgottenthe first touch by the time the ant brushes up against25the next hair. In other words, it loses the storage ofthe information, doesn’t close, and the anthappily meanders on. How does the plant encodeand store the information from the unassumingbug’s encounter with the first hair? How does it30 remember the first touch in order to react upon thesecond?Scientists have been puzzled by these questionsever since John Burdon-Sanderson’s early report onthe physiology of the Venus flytrap in 1882. A35 century later, Dieter Hodick and Andreas Sievers atthe University of Bonn in Germany proposed thatthe flytrap stored information regarding how manyhairs have been touched in the electric charge of itsleaf. Their model is quite elegant in its simplicity.40In their studies, they discovered that touching atrigger hair on the Venus flytrap causes an electricaction potential [a temporary reversal in theelectrical polarity of a cell membrane] thatinduces calcium channels to open in the trap (this45coupling of action potentials and the opening ofcalcium channels is similar to the processes thatoccur during communication between humanneurons), thus causing a rapid increase in theconcentration of calcium ions.50They proposed that the trap requires a relativelyhigh concentration of calcium in order to closeand that a single action potential from just onetrigger hair being touched does not reach this level.Therefore, a second hair needs to be stimulated to55push the calcium concentration over this thresholdand spring the trap. The encoding of the informationrequires maintaining a high enough level of calciumso that a second increase (triggered by touching thesecond hair) pushes the total concentration of60calcium over the threshold. As the calcium ionconcentrations dissipate over time, if the secondtouch and potential don’t happen quickly, the finalconcentration after the second trigger won’t be highenough to close the trap, and the memory is lost.65Subsequent research supports this model.Alexander Volkov and his colleagues at OakwoodUniversity in Alabama first demonstrated that it isindeed electricity that causes the Venus flytrap toclose. To test the model they rigged up very fine70electrodes and applied an electrical current to theopen lobes of the trap. This made the trap closewithout any direct touch to its trigger hairs (whilethey didn’t measure calcium levels, the currentlikely led to increases). When they modified this75experiment by altering the amount of electricalcurrent, Volkov could determine the exact electricalcharge needed for the trap to close. As long asfourteen microcoulombs—a tiny bit more than thestatic electricity generated by rubbing two balloons80together—flowed between the two electrodes, thetrap closed. This could come as one large burst or asa series of smaller charges within twenty seconds. If ittook longer than twenty seconds to accumulate thetotal charge, the trap would remain open.Q. The primary purpose of the passage is toa)discuss findings that offer a scientificexplanation for the Venus flytrap’s closingaction.b)present research that suggests that the Venusflytrap’s predatory behavior is both complex andunique among plants.c)identify the process by which the Venus flytrap’sclosing action has evolved.d)provide a brief overview of the Venus flytrap andits predatory behavior.Correct answer is option 'A'. Can you explain this answer? for SAT 2025 is part of SAT preparation. The Question and answers have been prepared according to the SAT exam syllabus. Information about Question is based on the following passage.This passage is adapted from Daniel Chamovitz, What a Plant Knows: A Field Guide to the Senses. ©2012 by Daniel Chamovitz.The Venus flytrap [Dionaea muscipula] needs toknow when an ideal meal is crawling across its leaves.Closing its trap requires a huge expense of energy,and reopening the trap can take several hours, so5 Dionaea only wants to spring closed when it’s surethat the dawdling insect visiting its surface is largeenough to be worth its time. The large black hairs ontheir lobes allow the Venus flytraps to literally feeltheir prey, and they act as triggers that spring the10 trap closed when the proper prey makes its wayacross the trap. If the insect touches just one hair, thetrap will not spring shut; but a large enough bug willlikely touch two hairs within about twenty seconds,and that signal springs the Venus flytrap into action.15 We can look at this system as analogous toshort-term memory. First, the flytrap encodes theinformation (forms the memory) that something (itdoesn’t know what) has touched one of its hairs.Then it stores this information for a number of20seconds (retains the memory) and finally retrievesthis information (recalls the memory) once a secondhair is touched. If a small ant takes a while to getfrom one hair to the next, the trap will have forgottenthe first touch by the time the ant brushes up against25the next hair. In other words, it loses the storage ofthe information, doesn’t close, and the anthappily meanders on. How does the plant encodeand store the information from the unassumingbug’s encounter with the first hair? How does it30 remember the first touch in order to react upon thesecond?Scientists have been puzzled by these questionsever since John Burdon-Sanderson’s early report onthe physiology of the Venus flytrap in 1882. A35 century later, Dieter Hodick and Andreas Sievers atthe University of Bonn in Germany proposed thatthe flytrap stored information regarding how manyhairs have been touched in the electric charge of itsleaf. Their model is quite elegant in its simplicity.40In their studies, they discovered that touching atrigger hair on the Venus flytrap causes an electricaction potential [a temporary reversal in theelectrical polarity of a cell membrane] thatinduces calcium channels to open in the trap (this45coupling of action potentials and the opening ofcalcium channels is similar to the processes thatoccur during communication between humanneurons), thus causing a rapid increase in theconcentration of calcium ions.50They proposed that the trap requires a relativelyhigh concentration of calcium in order to closeand that a single action potential from just onetrigger hair being touched does not reach this level.Therefore, a second hair needs to be stimulated to55push the calcium concentration over this thresholdand spring the trap. The encoding of the informationrequires maintaining a high enough level of calciumso that a second increase (triggered by touching thesecond hair) pushes the total concentration of60calcium over the threshold. As the calcium ionconcentrations dissipate over time, if the secondtouch and potential don’t happen quickly, the finalconcentration after the second trigger won’t be highenough to close the trap, and the memory is lost.65Subsequent research supports this model.Alexander Volkov and his colleagues at OakwoodUniversity in Alabama first demonstrated that it isindeed electricity that causes the Venus flytrap toclose. To test the model they rigged up very fine70electrodes and applied an electrical current to theopen lobes of the trap. This made the trap closewithout any direct touch to its trigger hairs (whilethey didn’t measure calcium levels, the currentlikely led to increases). When they modified this75experiment by altering the amount of electricalcurrent, Volkov could determine the exact electricalcharge needed for the trap to close. As long asfourteen microcoulombs—a tiny bit more than thestatic electricity generated by rubbing two balloons80together—flowed between the two electrodes, thetrap closed. This could come as one large burst or asa series of smaller charges within twenty seconds. If ittook longer than twenty seconds to accumulate thetotal charge, the trap would remain open.Q. The primary purpose of the passage is toa)discuss findings that offer a scientificexplanation for the Venus flytrap’s closingaction.b)present research that suggests that the Venusflytrap’s predatory behavior is both complex andunique among plants.c)identify the process by which the Venus flytrap’sclosing action has evolved.d)provide a brief overview of the Venus flytrap andits predatory behavior.Correct answer is option 'A'. Can you explain this answer? covers all topics & solutions for SAT 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Question is based on the following passage.This passage is adapted from Daniel Chamovitz, What a Plant Knows: A Field Guide to the Senses. ©2012 by Daniel Chamovitz.The Venus flytrap [Dionaea muscipula] needs toknow when an ideal meal is crawling across its leaves.Closing its trap requires a huge expense of energy,and reopening the trap can take several hours, so5 Dionaea only wants to spring closed when it’s surethat the dawdling insect visiting its surface is largeenough to be worth its time. The large black hairs ontheir lobes allow the Venus flytraps to literally feeltheir prey, and they act as triggers that spring the10 trap closed when the proper prey makes its wayacross the trap. If the insect touches just one hair, thetrap will not spring shut; but a large enough bug willlikely touch two hairs within about twenty seconds,and that signal springs the Venus flytrap into action.15 We can look at this system as analogous toshort-term memory. First, the flytrap encodes theinformation (forms the memory) that something (itdoesn’t know what) has touched one of its hairs.Then it stores this information for a number of20seconds (retains the memory) and finally retrievesthis information (recalls the memory) once a secondhair is touched. If a small ant takes a while to getfrom one hair to the next, the trap will have forgottenthe first touch by the time the ant brushes up against25the next hair. In other words, it loses the storage ofthe information, doesn’t close, and the anthappily meanders on. How does the plant encodeand store the information from the unassumingbug’s encounter with the first hair? How does it30 remember the first touch in order to react upon thesecond?Scientists have been puzzled by these questionsever since John Burdon-Sanderson’s early report onthe physiology of the Venus flytrap in 1882. A35 century later, Dieter Hodick and Andreas Sievers atthe University of Bonn in Germany proposed thatthe flytrap stored information regarding how manyhairs have been touched in the electric charge of itsleaf. Their model is quite elegant in its simplicity.40In their studies, they discovered that touching atrigger hair on the Venus flytrap causes an electricaction potential [a temporary reversal in theelectrical polarity of a cell membrane] thatinduces calcium channels to open in the trap (this45coupling of action potentials and the opening ofcalcium channels is similar to the processes thatoccur during communication between humanneurons), thus causing a rapid increase in theconcentration of calcium ions.50They proposed that the trap requires a relativelyhigh concentration of calcium in order to closeand that a single action potential from just onetrigger hair being touched does not reach this level.Therefore, a second hair needs to be stimulated to55push the calcium concentration over this thresholdand spring the trap. The encoding of the informationrequires maintaining a high enough level of calciumso that a second increase (triggered by touching thesecond hair) pushes the total concentration of60calcium over the threshold. As the calcium ionconcentrations dissipate over time, if the secondtouch and potential don’t happen quickly, the finalconcentration after the second trigger won’t be highenough to close the trap, and the memory is lost.65Subsequent research supports this model.Alexander Volkov and his colleagues at OakwoodUniversity in Alabama first demonstrated that it isindeed electricity that causes the Venus flytrap toclose. To test the model they rigged up very fine70electrodes and applied an electrical current to theopen lobes of the trap. This made the trap closewithout any direct touch to its trigger hairs (whilethey didn’t measure calcium levels, the currentlikely led to increases). When they modified this75experiment by altering the amount of electricalcurrent, Volkov could determine the exact electricalcharge needed for the trap to close. As long asfourteen microcoulombs—a tiny bit more than thestatic electricity generated by rubbing two balloons80together—flowed between the two electrodes, thetrap closed. This could come as one large burst or asa series of smaller charges within twenty seconds. If ittook longer than twenty seconds to accumulate thetotal charge, the trap would remain open.Q. The primary purpose of the passage is toa)discuss findings that offer a scientificexplanation for the Venus flytrap’s closingaction.b)present research that suggests that the Venusflytrap’s predatory behavior is both complex andunique among plants.c)identify the process by which the Venus flytrap’sclosing action has evolved.d)provide a brief overview of the Venus flytrap andits predatory behavior.Correct answer is option 'A'. Can you explain this answer?.
Solutions for Question is based on the following passage.This passage is adapted from Daniel Chamovitz, What a Plant Knows: A Field Guide to the Senses. ©2012 by Daniel Chamovitz.The Venus flytrap [Dionaea muscipula] needs toknow when an ideal meal is crawling across its leaves.Closing its trap requires a huge expense of energy,and reopening the trap can take several hours, so5 Dionaea only wants to spring closed when it’s surethat the dawdling insect visiting its surface is largeenough to be worth its time. The large black hairs ontheir lobes allow the Venus flytraps to literally feeltheir prey, and they act as triggers that spring the10 trap closed when the proper prey makes its wayacross the trap. If the insect touches just one hair, thetrap will not spring shut; but a large enough bug willlikely touch two hairs within about twenty seconds,and that signal springs the Venus flytrap into action.15 We can look at this system as analogous toshort-term memory. First, the flytrap encodes theinformation (forms the memory) that something (itdoesn’t know what) has touched one of its hairs.Then it stores this information for a number of20seconds (retains the memory) and finally retrievesthis information (recalls the memory) once a secondhair is touched. If a small ant takes a while to getfrom one hair to the next, the trap will have forgottenthe first touch by the time the ant brushes up against25the next hair. In other words, it loses the storage ofthe information, doesn’t close, and the anthappily meanders on. How does the plant encodeand store the information from the unassumingbug’s encounter with the first hair? How does it30 remember the first touch in order to react upon thesecond?Scientists have been puzzled by these questionsever since John Burdon-Sanderson’s early report onthe physiology of the Venus flytrap in 1882. A35 century later, Dieter Hodick and Andreas Sievers atthe University of Bonn in Germany proposed thatthe flytrap stored information regarding how manyhairs have been touched in the electric charge of itsleaf. Their model is quite elegant in its simplicity.40In their studies, they discovered that touching atrigger hair on the Venus flytrap causes an electricaction potential [a temporary reversal in theelectrical polarity of a cell membrane] thatinduces calcium channels to open in the trap (this45coupling of action potentials and the opening ofcalcium channels is similar to the processes thatoccur during communication between humanneurons), thus causing a rapid increase in theconcentration of calcium ions.50They proposed that the trap requires a relativelyhigh concentration of calcium in order to closeand that a single action potential from just onetrigger hair being touched does not reach this level.Therefore, a second hair needs to be stimulated to55push the calcium concentration over this thresholdand spring the trap. The encoding of the informationrequires maintaining a high enough level of calciumso that a second increase (triggered by touching thesecond hair) pushes the total concentration of60calcium over the threshold. As the calcium ionconcentrations dissipate over time, if the secondtouch and potential don’t happen quickly, the finalconcentration after the second trigger won’t be highenough to close the trap, and the memory is lost.65Subsequent research supports this model.Alexander Volkov and his colleagues at OakwoodUniversity in Alabama first demonstrated that it isindeed electricity that causes the Venus flytrap toclose. To test the model they rigged up very fine70electrodes and applied an electrical current to theopen lobes of the trap. This made the trap closewithout any direct touch to its trigger hairs (whilethey didn’t measure calcium levels, the currentlikely led to increases). When they modified this75experiment by altering the amount of electricalcurrent, Volkov could determine the exact electricalcharge needed for the trap to close. As long asfourteen microcoulombs—a tiny bit more than thestatic electricity generated by rubbing two balloons80together—flowed between the two electrodes, thetrap closed. This could come as one large burst or asa series of smaller charges within twenty seconds. If ittook longer than twenty seconds to accumulate thetotal charge, the trap would remain open.Q. The primary purpose of the passage is toa)discuss findings that offer a scientificexplanation for the Venus flytrap’s closingaction.b)present research that suggests that the Venusflytrap’s predatory behavior is both complex andunique among plants.c)identify the process by which the Venus flytrap’sclosing action has evolved.d)provide a brief overview of the Venus flytrap andits predatory behavior.Correct answer is option 'A'. Can you explain this answer? in English & in Hindi are available as part of our courses for SAT.
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Here you can find the meaning of Question is based on the following passage.This passage is adapted from Daniel Chamovitz, What a Plant Knows: A Field Guide to the Senses. ©2012 by Daniel Chamovitz.The Venus flytrap [Dionaea muscipula] needs toknow when an ideal meal is crawling across its leaves.Closing its trap requires a huge expense of energy,and reopening the trap can take several hours, so5 Dionaea only wants to spring closed when it’s surethat the dawdling insect visiting its surface is largeenough to be worth its time. The large black hairs ontheir lobes allow the Venus flytraps to literally feeltheir prey, and they act as triggers that spring the10 trap closed when the proper prey makes its wayacross the trap. If the insect touches just one hair, thetrap will not spring shut; but a large enough bug willlikely touch two hairs within about twenty seconds,and that signal springs the Venus flytrap into action.15 We can look at this system as analogous toshort-term memory. First, the flytrap encodes theinformation (forms the memory) that something (itdoesn’t know what) has touched one of its hairs.Then it stores this information for a number of20seconds (retains the memory) and finally retrievesthis information (recalls the memory) once a secondhair is touched. If a small ant takes a while to getfrom one hair to the next, the trap will have forgottenthe first touch by the time the ant brushes up against25the next hair. In other words, it loses the storage ofthe information, doesn’t close, and the anthappily meanders on. How does the plant encodeand store the information from the unassumingbug’s encounter with the first hair? How does it30 remember the first touch in order to react upon thesecond?Scientists have been puzzled by these questionsever since John Burdon-Sanderson’s early report onthe physiology of the Venus flytrap in 1882. A35 century later, Dieter Hodick and Andreas Sievers atthe University of Bonn in Germany proposed thatthe flytrap stored information regarding how manyhairs have been touched in the electric charge of itsleaf. Their model is quite elegant in its simplicity.40In their studies, they discovered that touching atrigger hair on the Venus flytrap causes an electricaction potential [a temporary reversal in theelectrical polarity of a cell membrane] thatinduces calcium channels to open in the trap (this45coupling of action potentials and the opening ofcalcium channels is similar to the processes thatoccur during communication between humanneurons), thus causing a rapid increase in theconcentration of calcium ions.50They proposed that the trap requires a relativelyhigh concentration of calcium in order to closeand that a single action potential from just onetrigger hair being touched does not reach this level.Therefore, a second hair needs to be stimulated to55push the calcium concentration over this thresholdand spring the trap. The encoding of the informationrequires maintaining a high enough level of calciumso that a second increase (triggered by touching thesecond hair) pushes the total concentration of60calcium over the threshold. As the calcium ionconcentrations dissipate over time, if the secondtouch and potential don’t happen quickly, the finalconcentration after the second trigger won’t be highenough to close the trap, and the memory is lost.65Subsequent research supports this model.Alexander Volkov and his colleagues at OakwoodUniversity in Alabama first demonstrated that it isindeed electricity that causes the Venus flytrap toclose. To test the model they rigged up very fine70electrodes and applied an electrical current to theopen lobes of the trap. This made the trap closewithout any direct touch to its trigger hairs (whilethey didn’t measure calcium levels, the currentlikely led to increases). When they modified this75experiment by altering the amount of electricalcurrent, Volkov could determine the exact electricalcharge needed for the trap to close. As long asfourteen microcoulombs—a tiny bit more than thestatic electricity generated by rubbing two balloons80together—flowed between the two electrodes, thetrap closed. This could come as one large burst or asa series of smaller charges within twenty seconds. If ittook longer than twenty seconds to accumulate thetotal charge, the trap would remain open.Q. The primary purpose of the passage is toa)discuss findings that offer a scientificexplanation for the Venus flytrap’s closingaction.b)present research that suggests that the Venusflytrap’s predatory behavior is both complex andunique among plants.c)identify the process by which the Venus flytrap’sclosing action has evolved.d)provide a brief overview of the Venus flytrap andits predatory behavior.Correct answer is option 'A'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of
Question is based on the following passage.This passage is adapted from Daniel Chamovitz, What a Plant Knows: A Field Guide to the Senses. ©2012 by Daniel Chamovitz.The Venus flytrap [Dionaea muscipula] needs toknow when an ideal meal is crawling across its leaves.Closing its trap requires a huge expense of energy,and reopening the trap can take several hours, so5 Dionaea only wants to spring closed when it’s surethat the dawdling insect visiting its surface is largeenough to be worth its time. The large black hairs ontheir lobes allow the Venus flytraps to literally feeltheir prey, and they act as triggers that spring the10 trap closed when the proper prey makes its wayacross the trap. If the insect touches just one hair, thetrap will not spring shut; but a large enough bug willlikely touch two hairs within about twenty seconds,and that signal springs the Venus flytrap into action.15 We can look at this system as analogous toshort-term memory. First, the flytrap encodes theinformation (forms the memory) that something (itdoesn’t know what) has touched one of its hairs.Then it stores this information for a number of20seconds (retains the memory) and finally retrievesthis information (recalls the memory) once a secondhair is touched. If a small ant takes a while to getfrom one hair to the next, the trap will have forgottenthe first touch by the time the ant brushes up against25the next hair. In other words, it loses the storage ofthe information, doesn’t close, and the anthappily meanders on. How does the plant encodeand store the information from the unassumingbug’s encounter with the first hair? How does it30 remember the first touch in order to react upon thesecond?Scientists have been puzzled by these questionsever since John Burdon-Sanderson’s early report onthe physiology of the Venus flytrap in 1882. A35 century later, Dieter Hodick and Andreas Sievers atthe University of Bonn in Germany proposed thatthe flytrap stored information regarding how manyhairs have been touched in the electric charge of itsleaf. Their model is quite elegant in its simplicity.40In their studies, they discovered that touching atrigger hair on the Venus flytrap causes an electricaction potential [a temporary reversal in theelectrical polarity of a cell membrane] thatinduces calcium channels to open in the trap (this45coupling of action potentials and the opening ofcalcium channels is similar to the processes thatoccur during communication between humanneurons), thus causing a rapid increase in theconcentration of calcium ions.50They proposed that the trap requires a relativelyhigh concentration of calcium in order to closeand that a single action potential from just onetrigger hair being touched does not reach this level.Therefore, a second hair needs to be stimulated to55push the calcium concentration over this thresholdand spring the trap. The encoding of the informationrequires maintaining a high enough level of calciumso that a second increase (triggered by touching thesecond hair) pushes the total concentration of60calcium over the threshold. As the calcium ionconcentrations dissipate over time, if the secondtouch and potential don’t happen quickly, the finalconcentration after the second trigger won’t be highenough to close the trap, and the memory is lost.65Subsequent research supports this model.Alexander Volkov and his colleagues at OakwoodUniversity in Alabama first demonstrated that it isindeed electricity that causes the Venus flytrap toclose. To test the model they rigged up very fine70electrodes and applied an electrical current to theopen lobes of the trap. This made the trap closewithout any direct touch to its trigger hairs (whilethey didn’t measure calcium levels, the currentlikely led to increases). When they modified this75experiment by altering the amount of electricalcurrent, Volkov could determine the exact electricalcharge needed for the trap to close. As long asfourteen microcoulombs—a tiny bit more than thestatic electricity generated by rubbing two balloons80together—flowed between the two electrodes, thetrap closed. This could come as one large burst or asa series of smaller charges within twenty seconds. If ittook longer than twenty seconds to accumulate thetotal charge, the trap would remain open.Q. The primary purpose of the passage is toa)discuss findings that offer a scientificexplanation for the Venus flytrap’s closingaction.b)present research that suggests that the Venusflytrap’s predatory behavior is both complex andunique among plants.c)identify the process by which the Venus flytrap’sclosing action has evolved.d)provide a brief overview of the Venus flytrap andits predatory behavior.Correct answer is option 'A'. Can you explain this answer?, a detailed solution for Question is based on the following passage.This passage is adapted from Daniel Chamovitz, What a Plant Knows: A Field Guide to the Senses. ©2012 by Daniel Chamovitz.The Venus flytrap [Dionaea muscipula] needs toknow when an ideal meal is crawling across its leaves.Closing its trap requires a huge expense of energy,and reopening the trap can take several hours, so5 Dionaea only wants to spring closed when it’s surethat the dawdling insect visiting its surface is largeenough to be worth its time. The large black hairs ontheir lobes allow the Venus flytraps to literally feeltheir prey, and they act as triggers that spring the10 trap closed when the proper prey makes its wayacross the trap. If the insect touches just one hair, thetrap will not spring shut; but a large enough bug willlikely touch two hairs within about twenty seconds,and that signal springs the Venus flytrap into action.15 We can look at this system as analogous toshort-term memory. First, the flytrap encodes theinformation (forms the memory) that something (itdoesn’t know what) has touched one of its hairs.Then it stores this information for a number of20seconds (retains the memory) and finally retrievesthis information (recalls the memory) once a secondhair is touched. If a small ant takes a while to getfrom one hair to the next, the trap will have forgottenthe first touch by the time the ant brushes up against25the next hair. In other words, it loses the storage ofthe information, doesn’t close, and the anthappily meanders on. How does the plant encodeand store the information from the unassumingbug’s encounter with the first hair? How does it30 remember the first touch in order to react upon thesecond?Scientists have been puzzled by these questionsever since John Burdon-Sanderson’s early report onthe physiology of the Venus flytrap in 1882. A35 century later, Dieter Hodick and Andreas Sievers atthe University of Bonn in Germany proposed thatthe flytrap stored information regarding how manyhairs have been touched in the electric charge of itsleaf. Their model is quite elegant in its simplicity.40In their studies, they discovered that touching atrigger hair on the Venus flytrap causes an electricaction potential [a temporary reversal in theelectrical polarity of a cell membrane] thatinduces calcium channels to open in the trap (this45coupling of action potentials and the opening ofcalcium channels is similar to the processes thatoccur during communication between humanneurons), thus causing a rapid increase in theconcentration of calcium ions.50They proposed that the trap requires a relativelyhigh concentration of calcium in order to closeand that a single action potential from just onetrigger hair being touched does not reach this level.Therefore, a second hair needs to be stimulated to55push the calcium concentration over this thresholdand spring the trap. The encoding of the informationrequires maintaining a high enough level of calciumso that a second increase (triggered by touching thesecond hair) pushes the total concentration of60calcium over the threshold. As the calcium ionconcentrations dissipate over time, if the secondtouch and potential don’t happen quickly, the finalconcentration after the second trigger won’t be highenough to close the trap, and the memory is lost.65Subsequent research supports this model.Alexander Volkov and his colleagues at OakwoodUniversity in Alabama first demonstrated that it isindeed electricity that causes the Venus flytrap toclose. To test the model they rigged up very fine70electrodes and applied an electrical current to theopen lobes of the trap. This made the trap closewithout any direct touch to its trigger hairs (whilethey didn’t measure calcium levels, the currentlikely led to increases). When they modified this75experiment by altering the amount of electricalcurrent, Volkov could determine the exact electricalcharge needed for the trap to close. As long asfourteen microcoulombs—a tiny bit more than thestatic electricity generated by rubbing two balloons80together—flowed between the two electrodes, thetrap closed. This could come as one large burst or asa series of smaller charges within twenty seconds. If ittook longer than twenty seconds to accumulate thetotal charge, the trap would remain open.Q. The primary purpose of the passage is toa)discuss findings that offer a scientificexplanation for the Venus flytrap’s closingaction.b)present research that suggests that the Venusflytrap’s predatory behavior is both complex andunique among plants.c)identify the process by which the Venus flytrap’sclosing action has evolved.d)provide a brief overview of the Venus flytrap andits predatory behavior.Correct answer is option 'A'. Can you explain this answer? has been provided alongside types of Question is based on the following passage.This passage is adapted from Daniel Chamovitz, What a Plant Knows: A Field Guide to the Senses. ©2012 by Daniel Chamovitz.The Venus flytrap [Dionaea muscipula] needs toknow when an ideal meal is crawling across its leaves.Closing its trap requires a huge expense of energy,and reopening the trap can take several hours, so5 Dionaea only wants to spring closed when it’s surethat the dawdling insect visiting its surface is largeenough to be worth its time. The large black hairs ontheir lobes allow the Venus flytraps to literally feeltheir prey, and they act as triggers that spring the10 trap closed when the proper prey makes its wayacross the trap. If the insect touches just one hair, thetrap will not spring shut; but a large enough bug willlikely touch two hairs within about twenty seconds,and that signal springs the Venus flytrap into action.15 We can look at this system as analogous toshort-term memory. First, the flytrap encodes theinformation (forms the memory) that something (itdoesn’t know what) has touched one of its hairs.Then it stores this information for a number of20seconds (retains the memory) and finally retrievesthis information (recalls the memory) once a secondhair is touched. If a small ant takes a while to getfrom one hair to the next, the trap will have forgottenthe first touch by the time the ant brushes up against25the next hair. In other words, it loses the storage ofthe information, doesn’t close, and the anthappily meanders on. How does the plant encodeand store the information from the unassumingbug’s encounter with the first hair? How does it30 remember the first touch in order to react upon thesecond?Scientists have been puzzled by these questionsever since John Burdon-Sanderson’s early report onthe physiology of the Venus flytrap in 1882. A35 century later, Dieter Hodick and Andreas Sievers atthe University of Bonn in Germany proposed thatthe flytrap stored information regarding how manyhairs have been touched in the electric charge of itsleaf. Their model is quite elegant in its simplicity.40In their studies, they discovered that touching atrigger hair on the Venus flytrap causes an electricaction potential [a temporary reversal in theelectrical polarity of a cell membrane] thatinduces calcium channels to open in the trap (this45coupling of action potentials and the opening ofcalcium channels is similar to the processes thatoccur during communication between humanneurons), thus causing a rapid increase in theconcentration of calcium ions.50They proposed that the trap requires a relativelyhigh concentration of calcium in order to closeand that a single action potential from just onetrigger hair being touched does not reach this level.Therefore, a second hair needs to be stimulated to55push the calcium concentration over this thresholdand spring the trap. The encoding of the informationrequires maintaining a high enough level of calciumso that a second increase (triggered by touching thesecond hair) pushes the total concentration of60calcium over the threshold. As the calcium ionconcentrations dissipate over time, if the secondtouch and potential don’t happen quickly, the finalconcentration after the second trigger won’t be highenough to close the trap, and the memory is lost.65Subsequent research supports this model.Alexander Volkov and his colleagues at OakwoodUniversity in Alabama first demonstrated that it isindeed electricity that causes the Venus flytrap toclose. To test the model they rigged up very fine70electrodes and applied an electrical current to theopen lobes of the trap. This made the trap closewithout any direct touch to its trigger hairs (whilethey didn’t measure calcium levels, the currentlikely led to increases). When they modified this75experiment by altering the amount of electricalcurrent, Volkov could determine the exact electricalcharge needed for the trap to close. As long asfourteen microcoulombs—a tiny bit more than thestatic electricity generated by rubbing two balloons80together—flowed between the two electrodes, thetrap closed. This could come as one large burst or asa series of smaller charges within twenty seconds. If ittook longer than twenty seconds to accumulate thetotal charge, the trap would remain open.Q. The primary purpose of the passage is toa)discuss findings that offer a scientificexplanation for the Venus flytrap’s closingaction.b)present research that suggests that the Venusflytrap’s predatory behavior is both complex andunique among plants.c)identify the process by which the Venus flytrap’sclosing action has evolved.d)provide a brief overview of the Venus flytrap andits predatory behavior.Correct answer is option 'A'. Can you explain this answer? theory, EduRev gives you an
ample number of questions to practice Question is based on the following passage.This passage is adapted from Daniel Chamovitz, What a Plant Knows: A Field Guide to the Senses. ©2012 by Daniel Chamovitz.The Venus flytrap [Dionaea muscipula] needs toknow when an ideal meal is crawling across its leaves.Closing its trap requires a huge expense of energy,and reopening the trap can take several hours, so5 Dionaea only wants to spring closed when it’s surethat the dawdling insect visiting its surface is largeenough to be worth its time. The large black hairs ontheir lobes allow the Venus flytraps to literally feeltheir prey, and they act as triggers that spring the10 trap closed when the proper prey makes its wayacross the trap. If the insect touches just one hair, thetrap will not spring shut; but a large enough bug willlikely touch two hairs within about twenty seconds,and that signal springs the Venus flytrap into action.15 We can look at this system as analogous toshort-term memory. First, the flytrap encodes theinformation (forms the memory) that something (itdoesn’t know what) has touched one of its hairs.Then it stores this information for a number of20seconds (retains the memory) and finally retrievesthis information (recalls the memory) once a secondhair is touched. If a small ant takes a while to getfrom one hair to the next, the trap will have forgottenthe first touch by the time the ant brushes up against25the next hair. In other words, it loses the storage ofthe information, doesn’t close, and the anthappily meanders on. How does the plant encodeand store the information from the unassumingbug’s encounter with the first hair? How does it30 remember the first touch in order to react upon thesecond?Scientists have been puzzled by these questionsever since John Burdon-Sanderson’s early report onthe physiology of the Venus flytrap in 1882. A35 century later, Dieter Hodick and Andreas Sievers atthe University of Bonn in Germany proposed thatthe flytrap stored information regarding how manyhairs have been touched in the electric charge of itsleaf. Their model is quite elegant in its simplicity.40In their studies, they discovered that touching atrigger hair on the Venus flytrap causes an electricaction potential [a temporary reversal in theelectrical polarity of a cell membrane] thatinduces calcium channels to open in the trap (this45coupling of action potentials and the opening ofcalcium channels is similar to the processes thatoccur during communication between humanneurons), thus causing a rapid increase in theconcentration of calcium ions.50They proposed that the trap requires a relativelyhigh concentration of calcium in order to closeand that a single action potential from just onetrigger hair being touched does not reach this level.Therefore, a second hair needs to be stimulated to55push the calcium concentration over this thresholdand spring the trap. The encoding of the informationrequires maintaining a high enough level of calciumso that a second increase (triggered by touching thesecond hair) pushes the total concentration of60calcium over the threshold. As the calcium ionconcentrations dissipate over time, if the secondtouch and potential don’t happen quickly, the finalconcentration after the second trigger won’t be highenough to close the trap, and the memory is lost.65Subsequent research supports this model.Alexander Volkov and his colleagues at OakwoodUniversity in Alabama first demonstrated that it isindeed electricity that causes the Venus flytrap toclose. To test the model they rigged up very fine70electrodes and applied an electrical current to theopen lobes of the trap. This made the trap closewithout any direct touch to its trigger hairs (whilethey didn’t measure calcium levels, the currentlikely led to increases). When they modified this75experiment by altering the amount of electricalcurrent, Volkov could determine the exact electricalcharge needed for the trap to close. As long asfourteen microcoulombs—a tiny bit more than thestatic electricity generated by rubbing two balloons80together—flowed between the two electrodes, thetrap closed. This could come as one large burst or asa series of smaller charges within twenty seconds. If ittook longer than twenty seconds to accumulate thetotal charge, the trap would remain open.Q. The primary purpose of the passage is toa)discuss findings that offer a scientificexplanation for the Venus flytrap’s closingaction.b)present research that suggests that the Venusflytrap’s predatory behavior is both complex andunique among plants.c)identify the process by which the Venus flytrap’sclosing action has evolved.d)provide a brief overview of the Venus flytrap andits predatory behavior.Correct answer is option 'A'. Can you explain this answer? tests, examples and also practice SAT tests.
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