egg

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egg

by jainrahul1985 » Sat Aug 28, 2010 6:38 am
When a caterpillar emerges from the egg on a tree branch, it immediately climbs upward until it finds a leaf bud to eat. Biologists thought that this behavior displayed an innate tendency to move in the direction opposite to the pull of gravity. In a recent experiment, a strong light source was placed at the bottom of a tree, and caterpillars, after hatching, climbed downward.

Which of the following hypotheses is best supported by the statements given?

(A) Caterpillars have an innate tendency to move in the direction of gravity.
(B) Newly hatched caterpillars are unable to see in the dark.
(C) Newly hatched caterpillars move towards the strongest light source in the environment.
(D) Newly hatched caterpillars move toward the leaf bud nearest to them.
(E) The eyes of newly hatched caterpillars become less sensitive to light over time

Why is the OA C . Please suggest

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by ashish2104 » Sat Aug 28, 2010 6:59 am
jainrahul1985 wrote:When a caterpillar emerges from the egg on a tree branch, it immediately climbs upward until it finds a leaf bud to eat. Biologists thought that this behavior displayed an innate tendency to move in the direction opposite to the pull of gravity. In a recent experiment, a strong light source was placed at the bottom of a tree, and caterpillars, after hatching, climbed downward.

Which of the following hypotheses is best supported by the statements given?

(A) Caterpillars have an innate tendency to move in the direction of gravity.
(B) Newly hatched caterpillars are unable to see in the dark.
(C) Newly hatched caterpillars move towards the strongest light source in the environment.
(D) Newly hatched caterpillars move toward the leaf bud nearest to them.
(E) The eyes of newly hatched caterpillars become less sensitive to light over time

Why is the OA C . Please suggest
When natural light is present, caterpillars move upward. When artificial light is present, they move downward.
Note that, it is not mentioned when the tests were conduted ie during day or night. SI the best hypothetisi that can be derived is that new ctaerpillars are attracted to strongest light source.

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by diebeatsthegmat » Sat Aug 28, 2010 6:34 pm
jainrahul1985 wrote:When a caterpillar emerges from the egg on a tree branch, it immediately climbs upward until it finds a leaf bud to eat. Biologists thought that this behavior displayed an innate tendency to move in the direction opposite to the pull of gravity. In a recent experiment, a strong light source was placed at the bottom of a tree, and caterpillars, after hatching, climbed downward.

Which of the following hypotheses is best supported by the statements given?

(A) Caterpillars have an innate tendency to move in the direction of gravity.
(B) Newly hatched caterpillars are unable to see in the dark.
(C) Newly hatched caterpillars move towards the strongest light source in the environment.
(D) Newly hatched caterpillars move toward the leaf bud nearest to them.
(E) The eyes of newly hatched caterpillars become less sensitive to light over time

Why is the OA C . Please suggest
]

yeah i also dont understand why the OA is C . i selected A because the scientist wanted to check if that caterpillar move in derection opposite to the pull of gravity, thats why there is an experiment. i dont know why its C?

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by reply2spg » Sat Aug 28, 2010 7:27 pm
You are correct in your explanation buddy. I eliminated B because of the same reason. Other than B and C all other are not relevant
ashish2104 wrote:
jainrahul1985 wrote:When a caterpillar emerges from the egg on a tree branch, it immediately climbs upward until it finds a leaf bud to eat. Biologists thought that this behavior displayed an innate tendency to move in the direction opposite to the pull of gravity. In a recent experiment, a strong light source was placed at the bottom of a tree, and caterpillars, after hatching, climbed downward.

Which of the following hypotheses is best supported by the statements given?

(A) Caterpillars have an innate tendency to move in the direction of gravity.
(B) Newly hatched caterpillars are unable to see in the dark.
(C) Newly hatched caterpillars move towards the strongest light source in the environment.
(D) Newly hatched caterpillars move toward the leaf bud nearest to them.
(E) The eyes of newly hatched caterpillars become less sensitive to light over time

Why is the OA C . Please suggest
When natural light is present, caterpillars move upward. When artificial light is present, they move downward.
Note that, it is not mentioned when the tests were conduted ie during day or night. SI the best hypothetisi that can be derived is that new ctaerpillars are attracted to strongest light source.
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by puneetdua » Sun Aug 29, 2010 4:33 am
Hey Ashish -


Earlier i thought answer is B, but after viewing the OA and your explanation , am bit confused.

According to you - If the reasoning is - caterpiller moves towards the strongest source of light -
then mentioning - it moves till it finds a leaf to eat (in absence of artificial light ) doesnt make much sense to me.

Can you please explain that.

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by Whitney Garner » Mon Oct 18, 2010 9:04 am
Received a PM asking me to respond. Don't see a source. Please cite the source (author) of the problem so I can respond!
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by rooster » Tue Oct 19, 2010 8:46 am
diebeatsthegmat wrote:
jainrahul1985 wrote:When a caterpillar emerges from the egg on a tree branch, it immediately climbs upward until it finds a leaf bud to eat. Biologists thought that this behavior displayed an innate tendency to move in the direction opposite to the pull of gravity. In a recent experiment, a strong light source was placed at the bottom of a tree, and caterpillars, after hatching, climbed downward.

Which of the following hypotheses is best supported by the statements given?

(A) Caterpillars have an innate tendency to move in the direction of gravity.
(B) Newly hatched caterpillars are unable to see in the dark.
(C) Newly hatched caterpillars move towards the strongest light source in the environment.
(D) Newly hatched caterpillars move toward the leaf bud nearest to them.
(E) The eyes of newly hatched caterpillars become less sensitive to light over time

Why is the OA C . Please suggest
]

yeah i also dont understand why the OA is C . i selected A because the scientist wanted to check if that caterpillar move in derection opposite to the pull of gravity, thats why there is an experiment. i dont know why its C?
The statement mentions that caterpillars naturally move up to find a leaflet, however, scientists had a study where the caterpillar moved down towards a light. If the caterpillar innately moves up, then it wouldn't be affected by the light source located at the bottom of the tree. This narrows your options to B and C, but the statement says nothing about caterpillars not seeing in the dark, so C is the viable choice.

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by ov25 » Thu Oct 21, 2010 12:34 pm
I think the answer is C.

However, it is interesting to note that "scientist's theory' in the passage is a misnomer. Just want to add that it can be inferred that the larvae are travelling toward sunlight (large source of light). And that the artificial source would be even more significant for them