Test: Practice Test - 8 - Class 10 MCQ

Question is based on the following passage.

This passage is from Carlos Ruiz Zafón, The Angel’s Game. ©2008 by Dragonworks, S.L. Translation ©2009 by Lucia Graves. The narrator, a writer, recalls his childhood in early twentieth-century Barcelona.
Even then my only friends were made of paper
and ink. At school I had learned to read and write
long before the other children. Where my school
friends saw notches of ink on incomprehensible
5 pages, I saw light, streets, and people. Words and the
mystery of their hidden science fascinated me, and I
saw in them a key with which I could unlock a
boundless world, a safe haven from that home, those
streets, and those troubled days in which even I
10 could sense that only a limited fortune awaited me.
My father didn’t like to see books in the house.
There was something about them—apart from the
letters he could not decipher—that offended him.
He used to tell me that as soon as I was ten he would
15 send me off to work and that I’d better get rid of all
my scatterbrained ideas if I didn’t want to end up a
loser, a nobody. I used to hide my books under the
mattress and wait for him to go out or fall asleep so
that I could read. Once he caught me reading at night
20 and flew into a rage. He tore the book from my
hands and flung it out of the window.
“If I catch you wasting electricity again, reading
all this nonsense, you’ll be sorry.”
My father was not a miser and, despite the
25 hardships we suffered, whenever he could he gave me
a few coins so that I could buy myself some treats like
the other children. He was convinced that I spent
them on licorice sticks, sunflower seeds, or sweets,
but I would keep them in a coffee tin under the bed,
30 and when I’d collected four or five reales I’d secretly
rush out to buy myself a book.
My favorite place in the whole city was the
Sempere & Sons bookshop on Calle Santa Ana. It
smelled of old paper and dust and it was my
35 sanctuary, my refuge. The bookseller would let me sit
on a chair in a corner and read any book I liked to
my heart’s content. He hardly ever allowed me to pay
for the books he placed in my hands, but when he
wasn’t looking I’d leave the coins I’d managed to
40 collect on the counter before I left. It was only small
change—if I’d had to buy a book with that pittance, I
would probably have been able to afford only a
booklet of cigarette papers. When it was time for me
to leave, I would do so dragging my feet, a weight on
45 my soul. If it had been up to me, I would have stayed
there forever.
One Christmas Sempere gave me the best gift I
have ever received. It was an old volume, read and
experienced to the full.
50 “Great Expectations, by Charles Dickens,” I read
on the cover.
I was aware that Sempere knew a few authors who
frequented his establishment and, judging by the care
with which he handled the volume, I thought
55 perhaps this Mr. Dickens was one of them.
“A friend of yours?”
“A lifelong friend. And from now on, he’s your
friend too.”
That afternoon I took my new friend home,
60 hidden under my clothes so that my father wouldn’t
see it. It was a rainy winter, with days as gray as lead,
and I read Great Expectations about nine times,
partly because I had no other book at hand, partly
because I did not think there could be a better one in
65 the whole world and I was beginning to suspect that
Mr. Dickens had written it just for me. Soon I was
convinced that I didn’t want to do anything else in
life but learn to do what Mr. Dickens had done.

Q. Which choice provides the best evidence for the answer to the previous question?

Question is based on the following passage.

This passage is from Carlos Ruiz Zafón, The Angel’s Game. ©2008 by Dragonworks, S.L. Translation ©2009 by Lucia Graves. The narrator, a writer, recalls his childhood in early twentieth-century Barcelona.
Even then my only friends were made of paper
and ink. At school I had learned to read and write
long before the other children. Where my school
friends saw notches of ink on incomprehensible
5 pages, I saw light, streets, and people. Words and the
mystery of their hidden science fascinated me, and I
saw in them a key with which I could unlock a
boundless world, a safe haven from that home, those
streets, and those troubled days in which even I
10 could sense that only a limited fortune awaited me.
My father didn’t like to see books in the house.
There was something about them—apart from the
letters he could not decipher—that offended him.
He used to tell me that as soon as I was ten he would
15 send me off to work and that I’d better get rid of all
my scatterbrained ideas if I didn’t want to end up a
loser, a nobody. I used to hide my books under the
mattress and wait for him to go out or fall asleep so
that I could read. Once he caught me reading at night
20 and flew into a rage. He tore the book from my
hands and flung it out of the window.
“If I catch you wasting electricity again, reading
all this nonsense, you’ll be sorry.”
My father was not a miser and, despite the
25 hardships we suffered, whenever he could he gave me
a few coins so that I could buy myself some treats like
the other children. He was convinced that I spent
them on licorice sticks, sunflower seeds, or sweets,
but I would keep them in a coffee tin under the bed,
30 and when I’d collected four or five reales I’d secretly
rush out to buy myself a book.
My favorite place in the whole city was the
Sempere & Sons bookshop on Calle Santa Ana. It
smelled of old paper and dust and it was my
35 sanctuary, my refuge. The bookseller would let me sit
on a chair in a corner and read any book I liked to
my heart’s content. He hardly ever allowed me to pay
for the books he placed in my hands, but when he
wasn’t looking I’d leave the coins I’d managed to
40 collect on the counter before I left. It was only small
change—if I’d had to buy a book with that pittance, I
would probably have been able to afford only a
booklet of cigarette papers. When it was time for me
to leave, I would do so dragging my feet, a weight on
45 my soul. If it had been up to me, I would have stayed
there forever.
One Christmas Sempere gave me the best gift I
have ever received. It was an old volume, read and
experienced to the full.
50 “Great Expectations, by Charles Dickens,” I read
on the cover.
I was aware that Sempere knew a few authors who
frequented his establishment and, judging by the care
with which he handled the volume, I thought
55 perhaps this Mr. Dickens was one of them.
“A friend of yours?”
“A lifelong friend. And from now on, he’s your
friend too.”
That afternoon I took my new friend home,
60 hidden under my clothes so that my father wouldn’t
see it. It was a rainy winter, with days as gray as lead,
and I read Great Expectations about nine times,
partly because I had no other book at hand, partly
because I did not think there could be a better one in
65 the whole world and I was beginning to suspect that
Mr. Dickens had written it just for me. Soon I was
convinced that I didn’t want to do anything else in
life but learn to do what Mr. Dickens had done.

Q. It can reasonably be inferred from the passage that the main reason that the narrator considers Great Expectations to be the best gift he ever received is because

Question is based on the following passage.

This passage is from Carlos Ruiz Zafón, The Angel’s Game. ©2008 by Dragonworks, S.L. Translation ©2009 by Lucia Graves. The narrator, a writer, recalls his childhood in early twentieth-century Barcelona.
Even then my only friends were made of paper
and ink. At school I had learned to read and write
long before the other children. Where my school
friends saw notches of ink on incomprehensible
5 pages, I saw light, streets, and people. Words and the
mystery of their hidden science fascinated me, and I
saw in them a key with which I could unlock a
boundless world, a safe haven from that home, those
streets, and those troubled days in which even I
10 could sense that only a limited fortune awaited me.
My father didn’t like to see books in the house.
There was something about them—apart from the
letters he could not decipher—that offended him.
He used to tell me that as soon as I was ten he would
15 send me off to work and that I’d better get rid of all
my scatterbrained ideas if I didn’t want to end up a
loser, a nobody. I used to hide my books under the
mattress and wait for him to go out or fall asleep so
that I could read. Once he caught me reading at night
20 and flew into a rage. He tore the book from my
hands and flung it out of the window.
“If I catch you wasting electricity again, reading
all this nonsense, you’ll be sorry.”
My father was not a miser and, despite the
25 hardships we suffered, whenever he could he gave me
a few coins so that I could buy myself some treats like
the other children. He was convinced that I spent
them on licorice sticks, sunflower seeds, or sweets,
but I would keep them in a coffee tin under the bed,
30 and when I’d collected four or five reales I’d secretly
rush out to buy myself a book.
My favorite place in the whole city was the
Sempere & Sons bookshop on Calle Santa Ana. It
smelled of old paper and dust and it was my
35 sanctuary, my refuge. The bookseller would let me sit
on a chair in a corner and read any book I liked to
my heart’s content. He hardly ever allowed me to pay
for the books he placed in my hands, but when he
wasn’t looking I’d leave the coins I’d managed to
40 collect on the counter before I left. It was only small
change—if I’d had to buy a book with that pittance, I
would probably have been able to afford only a
booklet of cigarette papers. When it was time for me
to leave, I would do so dragging my feet, a weight on
45 my soul. If it had been up to me, I would have stayed
there forever.
One Christmas Sempere gave me the best gift I
have ever received. It was an old volume, read and
experienced to the full.
50 “Great Expectations, by Charles Dickens,” I read
on the cover.
I was aware that Sempere knew a few authors who
frequented his establishment and, judging by the care
with which he handled the volume, I thought
55 perhaps this Mr. Dickens was one of them.
“A friend of yours?”
“A lifelong friend. And from now on, he’s your
friend too.”
That afternoon I took my new friend home,
60 hidden under my clothes so that my father wouldn’t
see it. It was a rainy winter, with days as gray as lead,
and I read Great Expectations about nine times,
partly because I had no other book at hand, partly
because I did not think there could be a better one in
65 the whole world and I was beginning to suspect that
Mr. Dickens had written it just for me. Soon I was
convinced that I didn’t want to do anything else in
life but learn to do what Mr. Dickens had done.

Q. Which choice provides the best evidence for the answer to the previous question?

Question is based on the following passage.

This passage is from Carlos Ruiz Zafón, The Angel’s Game. ©2008 by Dragonworks, S.L. Translation ©2009 by Lucia Graves. The narrator, a writer, recalls his childhood in early twentieth-century Barcelona.
Even then my only friends were made of paper
and ink. At school I had learned to read and write
long before the other children. Where my school
friends saw notches of ink on incomprehensible
5 pages, I saw light, streets, and people. Words and the
mystery of their hidden science fascinated me, and I
saw in them a key with which I could unlock a
boundless world, a safe haven from that home, those
streets, and those troubled days in which even I
10 could sense that only a limited fortune awaited me.
My father didn’t like to see books in the house.
There was something about them—apart from the
letters he could not decipher—that offended him.
He used to tell me that as soon as I was ten he would
15 send me off to work and that I’d better get rid of all
my scatterbrained ideas if I didn’t want to end up a
loser, a nobody. I used to hide my books under the
mattress and wait for him to go out or fall asleep so
that I could read. Once he caught me reading at night
20 and flew into a rage. He tore the book from my
hands and flung it out of the window.
“If I catch you wasting electricity again, reading
all this nonsense, you’ll be sorry.”
My father was not a miser and, despite the
25 hardships we suffered, whenever he could he gave me
a few coins so that I could buy myself some treats like
the other children. He was convinced that I spent
them on licorice sticks, sunflower seeds, or sweets,
but I would keep them in a coffee tin under the bed,
30 and when I’d collected four or five reales I’d secretly
rush out to buy myself a book.
My favorite place in the whole city was the
Sempere & Sons bookshop on Calle Santa Ana. It
smelled of old paper and dust and it was my
35 sanctuary, my refuge. The bookseller would let me sit
on a chair in a corner and read any book I liked to
my heart’s content. He hardly ever allowed me to pay
for the books he placed in my hands, but when he
wasn’t looking I’d leave the coins I’d managed to
40 collect on the counter before I left. It was only small
change—if I’d had to buy a book with that pittance, I
would probably have been able to afford only a
booklet of cigarette papers. When it was time for me
to leave, I would do so dragging my feet, a weight on
45 my soul. If it had been up to me, I would have stayed
there forever.
One Christmas Sempere gave me the best gift I
have ever received. It was an old volume, read and
experienced to the full.
50 “Great Expectations, by Charles Dickens,” I read
on the cover.
I was aware that Sempere knew a few authors who
frequented his establishment and, judging by the care
with which he handled the volume, I thought
55 perhaps this Mr. Dickens was one of them.
“A friend of yours?”
“A lifelong friend. And from now on, he’s your
friend too.”
That afternoon I took my new friend home,
60 hidden under my clothes so that my father wouldn’t
see it. It was a rainy winter, with days as gray as lead,
and I read Great Expectations about nine times,
partly because I had no other book at hand, partly
because I did not think there could be a better one in
65 the whole world and I was beginning to suspect that
Mr. Dickens had written it just for me. Soon I was
convinced that I didn’t want to do anything else in
life but learn to do what Mr. Dickens had done.

Q. The narrator indicates that he pays Sempere

Question is based on the following passage.

This passage is from Carlos Ruiz Zafón, The Angel’s Game. ©2008 by Dragonworks, S.L. Translation ©2009 by Lucia Graves. The narrator, a writer, recalls his childhood in early twentieth-century Barcelona.
Even then my only friends were made of paper
and ink. At school I had learned to read and write
long before the other children. Where my school
friends saw notches of ink on incomprehensible
5 pages, I saw light, streets, and people. Words and the
mystery of their hidden science fascinated me, and I
saw in them a key with which I could unlock a
boundless world, a safe haven from that home, those
streets, and those troubled days in which even I
10 could sense that only a limited fortune awaited me.
My father didn’t like to see books in the house.
There was something about them—apart from the
letters he could not decipher—that offended him.
He used to tell me that as soon as I was ten he would
15 send me off to work and that I’d better get rid of all
my scatterbrained ideas if I didn’t want to end up a
loser, a nobody. I used to hide my books under the
mattress and wait for him to go out or fall asleep so
that I could read. Once he caught me reading at night
20 and flew into a rage. He tore the book from my
hands and flung it out of the window.
“If I catch you wasting electricity again, reading
all this nonsense, you’ll be sorry.”
My father was not a miser and, despite the
25 hardships we suffered, whenever he could he gave me
a few coins so that I could buy myself some treats like
the other children. He was convinced that I spent
them on licorice sticks, sunflower seeds, or sweets,
but I would keep them in a coffee tin under the bed,
30 and when I’d collected four or five reales I’d secretly
rush out to buy myself a book.
My favorite place in the whole city was the
Sempere & Sons bookshop on Calle Santa Ana. It
smelled of old paper and dust and it was my
35 sanctuary, my refuge. The bookseller would let me sit
on a chair in a corner and read any book I liked to
my heart’s content. He hardly ever allowed me to pay
for the books he placed in my hands, but when he
wasn’t looking I’d leave the coins I’d managed to
40 collect on the counter before I left. It was only small
change—if I’d had to buy a book with that pittance, I
would probably have been able to afford only a
booklet of cigarette papers. When it was time for me
to leave, I would do so dragging my feet, a weight on
45 my soul. If it had been up to me, I would have stayed
there forever.
One Christmas Sempere gave me the best gift I
have ever received. It was an old volume, read and
experienced to the full.
50 “Great Expectations, by Charles Dickens,” I read
on the cover.
I was aware that Sempere knew a few authors who
frequented his establishment and, judging by the care
with which he handled the volume, I thought
55 perhaps this Mr. Dickens was one of them.
“A friend of yours?”
“A lifelong friend. And from now on, he’s your
friend too.”
That afternoon I took my new friend home,
60 hidden under my clothes so that my father wouldn’t
see it. It was a rainy winter, with days as gray as lead,
and I read Great Expectations about nine times,
partly because I had no other book at hand, partly
because I did not think there could be a better one in
65 the whole world and I was beginning to suspect that
Mr. Dickens had written it just for me. Soon I was
convinced that I didn’t want to do anything else in
life but learn to do what Mr. Dickens had done.

Q. As used in line 44, “weight” most nearly means

Question is based on the following passage.

This passage is from Carlos Ruiz Zafón, The Angel’s Game. ©2008 by Dragonworks, S.L. Translation ©2009 by Lucia Graves. The narrator, a writer, recalls his childhood in early twentieth-century Barcelona.
Even then my only friends were made of paper
and ink. At school I had learned to read and write
long before the other children. Where my school
friends saw notches of ink on incomprehensible
5 pages, I saw light, streets, and people. Words and the
mystery of their hidden science fascinated me, and I
saw in them a key with which I could unlock a
boundless world, a safe haven from that home, those
streets, and those troubled days in which even I
10 could sense that only a limited fortune awaited me.
My father didn’t like to see books in the house.
There was something about them—apart from the
letters he could not decipher—that offended him.
He used to tell me that as soon as I was ten he would
15 send me off to work and that I’d better get rid of all
my scatterbrained ideas if I didn’t want to end up a
loser, a nobody. I used to hide my books under the
mattress and wait for him to go out or fall asleep so
that I could read. Once he caught me reading at night
20 and flew into a rage. He tore the book from my
hands and flung it out of the window.
“If I catch you wasting electricity again, reading
all this nonsense, you’ll be sorry.”
My father was not a miser and, despite the
25 hardships we suffered, whenever he could he gave me
a few coins so that I could buy myself some treats like
the other children. He was convinced that I spent
them on licorice sticks, sunflower seeds, or sweets,
but I would keep them in a coffee tin under the bed,
30 and when I’d collected four or five reales I’d secretly
rush out to buy myself a book.
My favorite place in the whole city was the
Sempere & Sons bookshop on Calle Santa Ana. It
smelled of old paper and dust and it was my
35 sanctuary, my refuge. The bookseller would let me sit
on a chair in a corner and read any book I liked to
my heart’s content. He hardly ever allowed me to pay
for the books he placed in my hands, but when he
wasn’t looking I’d leave the coins I’d managed to
40 collect on the counter before I left. It was only small
change—if I’d had to buy a book with that pittance, I
would probably have been able to afford only a
booklet of cigarette papers. When it was time for me
to leave, I would do so dragging my feet, a weight on
45 my soul. If it had been up to me, I would have stayed
there forever.
One Christmas Sempere gave me the best gift I
have ever received. It was an old volume, read and
experienced to the full.
50 “Great Expectations, by Charles Dickens,” I read
on the cover.
I was aware that Sempere knew a few authors who
frequented his establishment and, judging by the care
with which he handled the volume, I thought
55 perhaps this Mr. Dickens was one of them.
“A friend of yours?”
“A lifelong friend. And from now on, he’s your
friend too.”
That afternoon I took my new friend home,
60 hidden under my clothes so that my father wouldn’t
see it. It was a rainy winter, with days as gray as lead,
and I read Great Expectations about nine times,
partly because I had no other book at hand, partly
because I did not think there could be a better one in
65 the whole world and I was beginning to suspect that
Mr. Dickens had written it just for me. Soon I was
convinced that I didn’t want to do anything else in
life but learn to do what Mr. Dickens had done.

Q. The word “friend” is used twice in lines 57-58 to

Question is based on the following passage.

This passage is from Carlos Ruiz Zafón, The Angel’s Game. ©2008 by Dragonworks, S.L. Translation ©2009 by Lucia Graves. The narrator, a writer, recalls his childhood in early twentieth-century Barcelona.
Even then my only friends were made of paper
and ink. At school I had learned to read and write
long before the other children. Where my school
friends saw notches of ink on incomprehensible
5 pages, I saw light, streets, and people. Words and the
mystery of their hidden science fascinated me, and I
saw in them a key with which I could unlock a
boundless world, a safe haven from that home, those
streets, and those troubled days in which even I
10 could sense that only a limited fortune awaited me.
My father didn’t like to see books in the house.
There was something about them—apart from the
letters he could not decipher—that offended him.
He used to tell me that as soon as I was ten he would
15 send me off to work and that I’d better get rid of all
my scatterbrained ideas if I didn’t want to end up a
loser, a nobody. I used to hide my books under the
mattress and wait for him to go out or fall asleep so
that I could read. Once he caught me reading at night
20 and flew into a rage. He tore the book from my
hands and flung it out of the window.
“If I catch you wasting electricity again, reading
all this nonsense, you’ll be sorry.”
My father was not a miser and, despite the
25 hardships we suffered, whenever he could he gave me
a few coins so that I could buy myself some treats like
the other children. He was convinced that I spent
them on licorice sticks, sunflower seeds, or sweets,
but I would keep them in a coffee tin under the bed,
30 and when I’d collected four or five reales I’d secretly
rush out to buy myself a book.
My favorite place in the whole city was the
Sempere & Sons bookshop on Calle Santa Ana. It
smelled of old paper and dust and it was my
35 sanctuary, my refuge. The bookseller would let me sit
on a chair in a corner and read any book I liked to
my heart’s content. He hardly ever allowed me to pay
for the books he placed in my hands, but when he
wasn’t looking I’d leave the coins I’d managed to
40 collect on the counter before I left. It was only small
change—if I’d had to buy a book with that pittance, I
would probably have been able to afford only a
booklet of cigarette papers. When it was time for me
to leave, I would do so dragging my feet, a weight on
45 my soul. If it had been up to me, I would have stayed
there forever.
One Christmas Sempere gave me the best gift I
have ever received. It was an old volume, read and
experienced to the full.
50 “Great Expectations, by Charles Dickens,” I read
on the cover.
I was aware that Sempere knew a few authors who
frequented his establishment and, judging by the care
with which he handled the volume, I thought
55 perhaps this Mr. Dickens was one of them.
“A friend of yours?”
“A lifelong friend. And from now on, he’s your
friend too.”
That afternoon I took my new friend home,
60 hidden under my clothes so that my father wouldn’t
see it. It was a rainy winter, with days as gray as lead,
and I read Great Expectations about nine times,
partly because I had no other book at hand, partly
because I did not think there could be a better one in
65 the whole world and I was beginning to suspect that
Mr. Dickens had written it just for me. Soon I was
convinced that I didn’t want to do anything else in
life but learn to do what Mr. Dickens had done.

Q. Which statement best characterizes the relationship between Sempere and Charles Dickens?

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.

Q. The primary purpose of the passage is to

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.

Q. Based on the passage, a significant advantage of the Venus flytrap’s requirement for multiple triggers is that it

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.

Q. Which choice provides the best evidence for the answer to the previous question?

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.

Q. The use of the phrases “dawdling insect” (line 6), “happily meanders” (line 27), and “unassuming bug’s encounter” (lines 28-29) in the first two paragraphs establishes a tone that is

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.

Q. In the second paragraph (lines 15-31), the discussion of short-term memory primarily functions to

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.

Q. According to the passage, which statement best explains why the Venus flytrap requires a second trigger hair to be touched within a short amount of time in order for its trap to close?

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.

Q. Which choice describes a scenario in which Hodick and Sievers’s model predicts that a Venus flytrap will NOT close around an insect?

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.

Q. As used in line 67, “demonstrated” most nearly means

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.

Q. Based on the passage, what potential criticism might be made of Volkov’s testing of Hodick and Sievers’s model?

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.

Q. Which choice provides the best evidence for the answer to the previous question?