OHIO GRADUATION TESTS
Science
Scoring Guidelines and Samples of
Scored Student Responses
Spring 2008
© 2008 by Ohio Department of Education
TABLE OF CONTENTS
Item 6: Item and Scoring Guidelines ....................................................................1
Item 6: Samples of Scored Student Responses ....................................................3
Item 12: Item and Scoring Guidelines ................................................................19
Item12: Samples of Scored Student Responses .................................................22
Item 18: Item and Scoring Guidelines ................................................................32
Item 18: Samples of Scored Student Responses ................................................34
Item 29: Item and Scoring Guidelines ................................................................44
Item 29: Samples of Scored Student Responses ................................................47
Item 35: Item and Scoring Guidelines ................................................................57
Item 35: Samples of Scored Student Responses …………………………………....61
Item 40: Item and Scoring Guidelines ................................................................77
Item 40: Samples of Scored Student Responses ................................................79
Science
Item 6
Spring 2008
Item and Scoring Guidelines
1
Item
6.
Thousands of acres of tropical rainforests are cut down each year, primarily for
farming and wood products. Identify two negative environmental
consequences of rainforest destruction. Explain the negative impact of each
consequence.
Respond in the space provided in your Answer Document. (4 points)
Sample Response for Item 6 (Extended Response):
N
N
Oxygen loss — Tropical rainforests generate a large percentage of the world’s
atmospheric oxygen. Rainforest destruction has a large effect on the makeup
of Earth’s atmosphere.
Loss of animal species. The loss of key organisms in any food web can result in
a “domino” effect, which could devastate entire ecosystems.
Scoring Guidelines for Item 6
Score Point
Description
4 points
The student identifies two environmental consequences of rainforest
destruction and explains the results of each.
3 points
The student identifies two environmental consequences of rainforest
destruction and explains the result of one.
2 points
The student identifies two environmental consequences of rainforest
destruction.
OR
The student identifies one environmental consequence of rainforest
destruction and explains the result.
1 point
The student identifies one environmental consequence of rainforest
destruction.
0 points
The student response does not meet the criteria to earn one point.
The response indicates inadequate or no understanding of the task.
It may only repeat information from the passage or prompt or
provide incorrect or irrelevant information. The student may have
written on a different topic or written “I don’t know.”
2
Science
Item 6
Spring 2008
Samples of Scored Student Responses
3
Score Point: 0
The student response demonstrates no understanding of the task. The response does
not identify any negative environmental consequences of rainforest destruction and
provides no explanation for any environmental impact. The statement that “anybody
can’t see the tropical rainforests” is not an environmental consequence and “the
animal lost the rainforests” is too vague to be given credit because it does not
address the loss as a loss of habitat.
4
Score Point: 0
The student response demonstrates no understanding of the task. The response does
not identify any negative environmental consequences of rainforest destruction and
provides no explanation for any environmental impact. “It wouldn’t be a good thing
because of the animal’s” is too vague to receive credit. Also, mentioning that if the
land is used for farming “I don’t think the soil for what they are growing would be to
good for it” does not address a negative environmental consequence of the
rainforest destruction, but a negative consequence for subsequent farming.
5
Score Point: 0
The student response demonstrates no understanding of the task. The response does
not identify any negative environmental consequences of rainforest destruction and
provides no explanation for any environmental impact. The response that “People
use the wood for paper, landscaping, & lots more” and that “there are already
enough farming and crops out there” is irrelevant to the question being asked.
6
Score Point: 1
The student response demonstrates an unclear understanding of the task by
identifying only one negative environmental consequence of rainforest destruction
without explaining the environmental impact of the consequence (rainforest
destruction is “cutting down on the earths oxygen”).
7
Score Point: 1
The student response demonstrates an unclear understanding of the task by
identifying only one negative environmental consequence of rainforest destruction
without explaining the environmental impact of the consequence (“it might cut
down the wildlife in that area”).
8
Score Point: 1
The student response demonstrates an unclear understanding of the task by
identifying only one negative environmental consequence of rainforest destruction
without explaining the environmental impact of the consequence (“the habitats of
many animals are being destroyed”). The reference to “tropical atmosphere” is too
vague to receive credit.
9
Score Point: 2
The student response demonstrates a partial understanding of the task by identifying
two negative environmental consequences of rainforest destruction without
explaining the environmental impact of either consequence (“killing animals and
destroying erbal remidies”).
10
Score Point: 2
The student response demonstrates a partial understanding of the task by identifying
only one negative environmental consequence of rainforest destruction and
explaining its environmental impact (“the loss of habitat for many species ... can
create extinction and lessen species diversity”). The reference to “resources &
minerals” is too vague, and medicines are not found in the rainforest; they must be
manufactured.
11
Score Point: 2
The student response demonstrates a partial understanding of the task by identifying
only one negative environmental consequence of rainforest destruction and
explaining its environmental impact (“If people keep cutting down trees we will loose
the amount of oxygen we have”).
12
Score Point: 3
The student response demonstrates an understanding of the task by identifying two
negative environmental consequences of rainforest destruction but explains the
environmental impact of only one consequence. One consequence is the loss of
“certain plant-life that is native to the rainforests” with the explanation that this could
result in the loss of “valuable medicinal plants.” Another consequence is that the
destruction causes “extinction of endangered species” that are “native to the
rainforests. However, no explanation for the consequence is provided.
13
Score Point: 3
The student response demonstrates an understanding of the task by identifying two
negative environmental consequences of rainforest destruction but explains the
environmental impact of only one consequence. One consequence is the loss of
trees which “give off the oxygen people need to survive” with the explanation that
without trees, “the oxygen level would decrease and the population could die.”
Another consequence is the loss of habitat “for all of the animals that can only
survive in that type of envionment.” However, no explanation for the consequence is
provided.
14
Score Point: 3
The student response demonstrates an understanding of the task by identifying two
negative environmental consequences of rainforest destruction but explains the
environmental impact of only one consequence. One consequence is “the decrease
in species of plants,” with the explanation that “undiscovered specimen have been
destroyed, when it could have been put to a great use” as a possible benefit to
humans. Another consequence is “the decrease in species of ... animals.” However,
no explanation for the consequence is provided.
15
Score Point: 4
The student response demonstrates a complete understanding of the task by
identifying two negative environmental consequences of rainforest destruction and
explaining the environmental impact of each. One negative consequence “is on
animals” because the animals “now has no place to live and so some of them die,”
resulting in a loss of local biodiversity. Another negative consequence “is on
pollution,” with the explanation that “the wood tooken from the trees will be used as
fuel” and when burned “makes the pollution rate go higher.”
16
Score Point: 4
The student response demonstrates a complete understanding of the task by
identifying two negative environmental consequences of rainforest destruction and
explaining the environmental impact of each. When rainforest destruction occurs,
“we kill the animals in the rainforest along with it,” which is a negative consequence
because “the homes we have destroyed” reduces habitats, leaving the animals with
nowhere to live. Another consequence with explanation is that rainforest destruction
not only puts “the lives of the plants & animals at risk, but our lives also b/c we
receive oxygen from the rainforest.”
17
Score Point: 4
The student response demonstrates a complete understanding of the task by
identifying two negative environmental consequences of rainforest destruction and
explaining the environmental impact of each. One negative consequence with
explanation “is that the animals ... have to find a place elsewhere” to live because of
habitat loss. Another consequence with explanation is that the destruction of the
forest habitat may cause the animals “to die out.” If “another animal needs them to
live,” it will cause a “domino effect” on the food chain.
18
Science
Item 12
Spring 2008
Item and Scoring Guidelines
19
Use the information below to answer question 12.
A group of students designs an experiment to test how an herbicide affects
pepper plants and weeds. Eight plots are tested, each of which holds 25 pepper
plants and a variety of weeds. Plots 1 and 2 are not treated; plots 3 – 8 are treated
with varying amounts of weed-killing herbicide. The weeds are counted in each
plot during week 1. The herbicide is applied during week 2, and the weeds are
counted again in week 3. The data are shown in the table below.
Item
12.
In a follow-up study, a student allows weeds to grow in a previously cleared
plot for several weeks. The student counts the number of weeds and then
treats the plot with the recommended dose of herbicide. The student observes
that several weeds survive and their offspring soon replace the weeds that
were killed by the initial application of the herbicide. Propose a hypothesis to
explain why several of the weeds survived the herbicide application.
Explain how this hypothesis could be tested. Respond in the space provided in
your Answer Document. (2 points)
Sample Response for Item 12 (Short Answer):
Some weeds may have received a smaller amount of the herbicide than other weeds
(unequal application within the plot). The student could test this hypothesis by
determining the concentration of herbicide in the tissues of the live weeds and
comparing them to the concentrations in the dead weeds.
20
Scoring Guidelines for Item 12
Score Point
Description
2 points
The student proposes a logical hypothesis that could explain the
survival of the weeds and explains how this hypothesis could be
tested scientifically.
1 point
The student proposes a logical hypothesis that could explain the
survival of the weeds but the explanation of how to test the
hypothesis is flawed or illogical.
0 points
The student response demonstrates no understanding of the task.
The response may provide incorrect information or be irrelevant to
the task. The student may repeat information from the passage or
prompt or may have written “I don’t know.”
21
Science
Item 12
Spring 2008
Samples of Scored Student Responses
22
Score Point: 0
The student response demonstrates no understanding of the task. The hypothesis
(“The weeds could have survived from the herbicide because the application was
also taking effect on another plant, the peppers”) is not logical and does not explain
why several of the weeds survived herbicide application.
23
Score Point: 0
The student response demonstrates no understanding of the task. Neither hypothesis
is logical (“because bugs hadn’t got to them yet or they were’nt fully grown”) and
neither explains why several of the weeds survived herbicide application.
24
Score Point: 0
The student response demonstrates no understanding of the task. The hypothesis (“a
cuple of weeds surviving based on how much time passed and how long the
herbicide is good for”) does not explain why several of the weeds survived the
herbicide application.
25
Score Point: 1
The student response demonstrates a partial understanding of the task by providing
a logical hypothesis that could explain why several of the weeds survived the
herbicide application (“because they were not exposed to it as much as the other
ones were”), but it does not provide a clear explanation for how the hypothesis could
be tested.
26
Score Point: 1
The student response demonstrates a partial understanding of the task by providing
a logical hypothesis that could explain why several of the weeds survived the
herbicide application (“the plants where immune to the herbicide so it did not affect
them”), but it does not provide a clear explanation for how the hypothesis could be
tested.
27
Score Point: 1
The student response demonstrates a partial understanding of the task by providing
a logical hypothesis that could explain why several of the weeds survived the
herbicide application (“those weeds carry a gene for herbicide resistance”), but the
explanation of how to test the hypothesis is flawed because genes do not have a
karyotype.
28
Score Point: 2
The student response demonstrates a complete understanding of the task by
providing both a logical hypothesis that could explain why several of the weeds
survived the herbicide application (“those weeds that survived probably had a
resistence gene that the ones that died didnt have”) and a full explanation of how
the hypothesis could be tested (“taking the plants in for genetic test”).
29
Score Point: 2
The student response demonstrates a complete understanding of the task by
providing both a logical hypothesis that could explain why several of the weeds
survived the herbicide application (“Some of the weeds survived because there was
an uneven distribution of the herbicide”) and a full explanation of how the
hypothesis could be tested (“measuring the level of the chemicals in random
plants”).
30
Score Point: 2
The student response demonstrates a complete understanding of the task by
providing both a logical hypothesis that could explain why several of the weeds
survived the herbicide application (“The herbicide might have not been enough to
kill the weeds”) and a full explanation of how the hypothesis could be tested (“they
could of had 2 plots both with the same amount of weeds. The first plot with the
recommended amount and the second one with the amount of herbicide”).
31
Science
Item 18
Spring 2008
Item and Scoring Guidelines
32
Item
18.
Individuals suffering from debilitating and sometimes terminal diseases often
advocate a more rapid development cycle for approving new drug
treatments. If the development cycle is accelerated, describe one potential
benefit and one potential hazard of treating a disease.
Respond in the space provided in your Answer Document. (2 points)
Sample Response for Item 18 (Short Answer):
Benefits:
If new drug treatments are made available quickly:
N more lives might be saved.
N their effectiveness (or lack of effectiveness) can be more quickly evaluated
and if necessary, research into alternative treatments will ensue more
promptly.
N Other acceptable responses.
Hazards:
If new drug treatments are pushed through quickly and not adequately tested:
N side effects may be overlooked, which could result in complications or death
to the users.
N interactions with other medications may not be properly assessed, resulting in
complications.
N Long-term effects on many individuals may not be identified because of rapid
development.
N Other acceptable responses.
Scoring Guidelines for Item 18
Score Point
Description
2 points
The response demonstrates a complete understanding of the task by
describing one potential benefit AND one potential hazard of speeding
up the development cycle for new drugs.
1 point
The response demonstrates a partial understanding of the task by
describing one potential benefit OR one potential hazard of speeding
up the development cycle for new drugs.
0 points
The response demonstrates no understanding of the task. The response
may provide incorrect information or be irrelevant to the task.
33
34
Science
Item 18
Spring 2008
Samples of Scored Student Responses
35
Score Point: 0
The student response demonstrates no understanding of the task. The response
describes a benefit (“to get well and feel better sooner”) which does not receive
credit because the student is indicating accelerated treatment, not development.
The response describes a hazard (“you could become immune to the treatment
sooner”) of the patient becoming resistant to the drug. Both responses fail to
describe a benefit or a hazard of speeding up the drug development cycle.
36
Score Point: 0
The student response demonstrates no understanding of the task. The response
describes a benefit (“the disease might not kill them and it could go away”) of a
faster acting drug not a faster development process. The response describes a
hazard (“the body might not be used to the drug and it might not work”) that is too
vague to receive credit. Both responses fail to describe a benefit or a hazard of
speeding up the drug development cycle.
37
Score Point: 0
The student response demonstrates no understanding of the task. The response
describes a benefit (“they may come up with a treatment if they keep trying”) of
repeated attempts to develop a new drug. The response describes a hazard (“if they
don’t get the right treatment then they could kill someone or make things worst”) of a
new drug treatment. Both responses fail to describe a benefit or a hazard of
speeding up the drug development cycle.
38
Score Point: 1
The student response demonstrates a partial understanding of the task by describing
one benefit (“it makes the developement process faster, which means quicker
treatments”) of speeding up the development cycle for new drugs. An additional
detail (“the disease might not be all the way cured”) fails to describe a hazard of
speeding up the development cycle.
39
Score Point: 1
The student response demonstrates a partial understanding of the task by describing
one benefit (“the disease will get treated faster that it already was”) of speeding up
the development cycle for new drugs. A description of a hazard of speeding up the
development cycle for new drugs was not provided.
40
Score Point: 1
The student response demonstrates a partial understanding of the task by describing
one hazard (“a patient may receive a drug and might get a side effect that was not
know about because the cure wasn’t tested as thoroughly”) of speeding up the
development cycle for new drugs. An additional detail (“the patients can be treated
with the most-up-to-date cures”) fails to describe a benefit of speeding up the
development cycle.
41
Score Point: 2
The student response demonstrates a complete understanding of the task by
providing a description of a benefit (“more lives could be saved because more
people would be affected”) and a hazard (“drug treatment might not be tested
enough + so patients might be subjected to side effects”) of speeding up the
development cycle for new drugs.
42
Score Point: 2
The student response demonstrates a complete understanding of the task by
providing a description of a benefit (“help cure or reduce the effets of a certain
disease”) and a hazard (“they arent as well tested and could cause harm to
individuals”) of speeding up the development cycle for new drugs.
43
Score Point: 2
The student response demonstrates a complete understanding of the task by
providing a description of a benefit (“the drug would take an immediate role in
improving the health of the patient”) and a hazard (“negative side effects that result
from long term use of the drug might not appear in the short amount of time thats
being used to develop and test the drugs”) of speeding up the development cycle
for new drugs.
44
Science
Item 29
Spring 2008
Item and Scoring Guidelines
45
Item
29.
A sailboat is moving at a constant velocity of 8 km/h eastward as shown in the
picture below.
Describe two opposing forces acting on the boat and explain how each force
affects the boat.
Respond in the space provided in your Answer Document. (2 points)
Sample Response for Item 29 (Short Answer):
The two forces that are opposing are the force on the sail and the force of the water
on the moving boat. The wind pushes against the sail, which causes the boat to
move forward. As the boat moves forward through the water, friction is formed where
the water resists the moving boat.
Scoring Guidelines for Item 29
Score Point
Description
2 points
The student response demonstrates a complete understanding of the
task by describing two opposing forces acting on the boat and
explaining how the forces affect the boat’s motion.
46
1 point
The student response demonstrates a partial understanding of the task
by describing two opposing forces acting on the boat.
OR
The student describes one force acting on the boat and explains how
that force affects the boat’s motion.
0 points
The student response demonstrates no understanding of the task. The
response may provide incorrect information or be irrelevant to the task.
The student may only repeat information from the passage or prompt
without any supporting information responsive to the task. The student
may have written “I don’t know.”
47
Science
Item 29
Spring 2008
Samples of Scored Student Responses
48
Score Point: 0
The student response demonstrates no understanding of the task. Several forces are
identified, but because they are not opposing, the response does not receive credit.
In addition, no explanations of how any of the identified forces affect the motion of
the boat were provided.
49
Score Point: 0
The student response demonstrates no understanding of the task. Only one force is
identified, and the effect on the motion of the boat is incorrectly explained (“gravity
is pulling the boat back and forth”).
50
Score Point: 0
The student response demonstrates no understanding of the task. Only one force is
identified, and the effect of that force on the motion of the boat is not explained
(“the wind ... could be blowing in a different direction”).
51
Score Point: 1
The student response demonstrates a partial understanding of the task by identifying
two opposing forces acting on the boat without providing adequate explanations for
either force. The response identifies “water, wind” as two the opposing forces acting
on the boat.
52
Score Point: 1
The student response demonstrates a partial understanding of the task by identifying
two opposing forces acting on the boat without providing adequate explanations for
either force. The response identifies that the “wind is pushing the sail” and the “water
is floing at an opposite.” The explanation that the water force is “causing a smoother
ride” is too vague.
53
Score Point: 1
The student response demonstrates a partial understanding of the task by identifying
one force acting on the boat and explaining how that force affects the motion of the
boat. Even though the response provides two forces and explanations, because the
two forces do not oppose each other, the response receives credit for only one
identification and explanation. The response identifies and explains that “gravity is
pushing the boat down into the water.”
54
Score Point: 2
The student response demonstrates a complete understanding of the task by
identifying two opposing forces and explaining how each force affects the boat. The
opposing forces are “friction from the water” and “the forward pushing force on the
sails.” The response explains that friction from the water “attempts to hold the boat in
place” and the wind on the sail is “trying to move the boat.”
55
Score Point: 2
The student response demonstrates a complete understanding of the task by
identifying two opposing forces and explaining how each force affects the boat. The
response identifies “wind and the water current” as the two opposing forces. The
response explains that the wind “is blowing or pushing on the boat” and the water
current “is pulling on the boat.”
56
Score Point: 2
The student response demonstrates a complete understanding of the task by
identifying two opposing forces and explaining how each force affects the boat. The
response provides two identifications with explanations (“The wind is acting on the
boat causing it to move east” and “The water” is causing the boat “to go slower”).
57
Science
Item 35
Spring 2008
Item and Scoring Guidelines
58
Item
35.
Environmental monitoring of a lake located to the southeast of a factory has
shown a consistent decrease in pH over the period of a year. A researcher
investigating the pH change hypothesizes that either a factory or a farm along
the river is responsible for the pH change. The river flows into the lake.
The researcher collects a water sample from locations Y and Z in the diagram
and runs pH analyses on each sample. He finds that the pH in sample Z is
lower than the pH in sample Y and concludes that the factory is responsible for
the low pH values in the lake.
Based on the diagram and the researcher’s investigation, provide two reasons
why this may not be a valid conclusion. Describe how each reason could
invalidate the conclusion.
Respond in the space provided in your Answer Document. (4 points)
Sample Response for Item 35 (Extended Response):
The researcher's conclusion my not be valid because he did not measure the water
pH at point X. The water at this point may have a lower pH before it reaches the farm
or residential area. Another reason the conclusion may be invalid is that the
researcher did not measure the water near the residential area. Chemical from the
houses or from the lawns could runoff into the water and lower the pH.
59
Scoring Guidelines for Item 35
Score Point
Description
4 points
The response demonstrates a complete understanding of the task by
providing two reasons why the conclusion may not be valid, and by
describing how each reason could invalidate the conclusion. The
response is focused and relevant to the task.
3 points
The response demonstrates an understanding of the task by providing
two reasons why the conclusion may not be valid and describing how
one reason could invalidate the conclusion.
OR
The response provides one reason why the conclusion may not be valid
and describes how that reason could invalidate the conclusion and
describes one other way the conclusion could be invalidated without
providing a specific reason (e.g., “it could have just been an anomaly
in those samples”).
2 points
The response demonstrates a partial understanding of the task by
providing two reasons why the conclusion may not be valid.
OR
The response provides one reason why the conclusion may not be valid
and describes how that reason could invalidate the conclusion.
OR
The response describes two ways the conclusion could be invalidated
without providing a specific reason (e.g., “it could have just been an
anomaly in those samples” and “it would be impossible to tell where the
pollution came from”).
1 point
The response demonstrates an unclear understanding of the task by
providing one reason why the conclusion may not be valid.
OR
The response describes one way the conclusion could be invalidated
without providing a specific reason.
60
0 points
The response demonstrates no understanding of the task. The response
may provide incorrect information or be irrelevant to the task.
61
Science
Item 35
Spring 2008
Samples of Scored Student Responses
62
Score Point: 0
The student response demonstrates no understanding of the task. The response is not
relevant to the prompt.
63
Score Point: 0
The student response demonstrates no understanding of the task. The description of
“cleaning the water” is unclear and demonstrates no understanding of the task.
64
Score Point: 0
The student response demonstrates no understanding of the task. The description
“The factory burn stuff” is not relevant to the question.
65
Score Point: 1
The student response demonstrates an unclear understanding of the task by
providing a reason the conclusion may not be valid (“he never went to the top of the
river and looked at X”). The descriptions of the river (“Z is more open ...Y is really
closed in”) and the description of their effect on pH (“pH won’t fell the whole thing ...
has the most pH probally”) do not correctly address why the conclusion may not be
valid.
66
Score Point: 1
The student response demonstrates an unclear understanding of the task by
providing one reason (“one test cant be the answer ... more test need to be Ran!”).
The explanation, “their could be more water where Z is tha Y... would dulote (sp) the
PH in the water in Z” does not address a correct reason or description of how the
conclusion could be invalidated.
67
Score Point: 1
The student response demonstrates an unclear understanding of the task by
describing how the conclusion could be invalidated (“the equipment was broken”).
The response does not state why this description is an anomaly. The response also
fails to provide a second reason and description of how the conclusion could be
invalidated.
68
Score Point: 2
The student response demonstrates a partial understanding of the task by providing
one reason (“he didn’t test the pH level ... near the residential area”) and one
description (“residential area could have mixed with the test site ‘Y’ ”). The response
does not provide a second reason or a second description of how the conclusion
could be invalidated.
69
Score Point: 2
The student response demonstrates a partial understanding of the task by providing
one reason (“there is a residential across the river”) and one description (“they can’t
specify exactly if it was from the factory or from residential”). The response does not
provide a second reason or a second description of how the conclusion can be
invalidated.
70
Score Point: 2
The student response demonstrates a partial understanding of the task by providing
one reason (because “the water is flowing downwards”) and one description (“could
be decreasing because of the farm or even the residential area, but they wouldn’t
know”). The response does not provide a second reason or a second description
how the conclusion can be invalidated.
71
Score Point: 3
The student response demonstrates an understanding of the task by describing two
ways the conclusion could be invalidated (“the residential houses could play a roll”
and “the moving of the H2O moved [the pollution] down stream”) and giving one
reason (“Farm effected the Ph level”). The response does not provide a specific
description of how the residential houses or the farm could invalidate the conclusion.
72
Score Point: 3
The student response demonstrates an understanding of the task by describing two
reasons (“the researcher never analyzed location X” and “the river has gone by a
farm, homes, and a factory” and the researcher did not account for all of these
locations) and one way the conclusion could be invalidated (“all of those places
could be factors”). The response does not describe how not taking a sample at
location X could invalidate the conclusion.
73
Score Point: 3
The student response demonstrates an understanding of the task by describing two
ways the conclusion could be invalidated (“water at the farm could have the low pH
and just get increasingly worse as it flows toward location Y” and “The low pH could
also be coming from location X”) and giving one reason (“the River flows
southeast”). The response does not provide a reason that “The low pH could also be
coming from location X.”
74
Score Point: 4
The student response demonstrates a complete understanding of the task by
providing two reasons that the researcher’s conclusion may not be valid and
describing how each reason invalidates the conclusion. The first reason is “the
researcher did not test the ph in location X” with the explanation that “there could be
a substance ... eventually mixing with the other locations.” The second reason is “the
researcher should have considered the residential area also” with the explanation of
“the sewer system possibly running into the lake.”
75
Score Point: 4
The student response demonstrates a complete understanding of the task by
providing two reasons that the researcher’s conclusion may not be valid and
describing how each reason invalidates the conclusion. The first reason is “the
researcher did not take the residential area into consideration,” with the explanation
that “pollution from these homes could be the explanation.” The second reason the
conclusion may not be valid is “the farm,” with the explanation that “he was testing
water before it had time to mix thourghly with the chemicals.”
76
Score Point: 4
The student response demonstrates a complete understanding of the task by
providing two reasons that the researcher’s conclusion may not be valid and
describing how each reason invalidates the conclusion. The first reason is “the
researcher did not take a sample from point X,” with the explanation that if pH at
point X “is low then it is neither the farm nor the factories fault.” The second reason
the conclusion may not be valid is that the researcher failed to account for “the
residential area,” with the explanation that “he doesn’t know what part the residents
play in the river’s pH.”
77
Science
Item 40
Spring 2008
Item and Scoring Guidelines
78
Item
40.
Significant progress has been made in the development of oxygen-carrying
solutions that may replace whole blood. Describe two reasons why
researchers are so interested in developing artificial blood to replace the use
of whole blood.
Respond in the space provided in your Answer Document. (2 points)
Sample Response for Item 40 (Short Answer):
Sample Response:
N
N
N
N
N
N
N
Blood is perishable/has a short shelf-life.
Long- and short-term storage of blood is expensive.
Donors are not always available/dependable and supplies may run short,
especially during major disasters.
Purity issues, non-tainted blood supplies (e.g., hepatitis, HIV, etc.)
Certain blood-types are very rare.
Could eliminate the need for compatibility testing.
Other acceptable responses.
Scoring Guidelines for Item 40
Score Point
Description
2 points
The response demonstrates a complete understanding of the task by
describing two reasons why researchers are interested in developing
artificial blood.
1 point
The response demonstrates a partial understanding of the task by
describing one reason why researchers are interested in developing
artificial blood.
0 points
The response demonstrates no understanding of the task. The response
may provide incorrect information or be irrelevant to the task.
79
Science
Item 40
Spring 2008
Samples of Scored Student Responses
80
Score Point: 0
The student response demonstrates no understanding of the task. The response “to
save lives” is too vague to receive credit. The response “Maybe they could us this
artificial blood to clone people” is incorrect. The responses given are not reasons why
researchers are interested in developing artificial blood.
81
Score Point: 0
The student response demonstrates no understanding of the task. The response,
“someone might need a transplat or to help with the diseases” does not specify what
advantage artificial blood would have over whole blood for use in transplants or
treatment of diseases. The responses given are not reasons why researchers are
interested in developing artificial blood.
82
Score Point: 0
The student response demonstrates no understanding of the task. The response,
“researchers have significant progress that it is a better solution. It saves the whole
blood for people who need it the most. Artificial blood is good to use when
experimenting or any other involvements” is too vague to receive credit. The
responses given are not reasons why researchers are interested in developing
artificial blood.
83
Score Point: 1
The student response demonstrates a partial understanding of the task by describing
one reason why researchers are interested in developing artificial blood. The
response states that “oxygen carrying substances would be more efficient and easier
to get than regular blood (doners).”
84
Score Point: 1
The student response demonstrates a partial understanding of the task by describing
one reason why researchers are interested in developing artificial blood. The
response states that “you can produce the artificial blood so future blood donations
wouldn’t be necessary.”
85
Score Point: 1
The student response demonstrates a partial understanding of the task by describing
one reason why researchers are interested in developing artificial blood. The
response states that “some people need blood transplants and maybe there isnt a
doner for that blood type.”
86
Score Point: 2
The student response demonstrates a complete understanding of the task by
describing two reasons why researchers are interested in developing artificial blood.
The response lists many appropriate reasons, two of which are that there would be
less need for human donors (“it would get rid of the need for blood banks”) and that
blood could be more easily stored (“it could be stored in first-aid kits”).
87
Score Point: 2
The student response demonstrates a complete understanding of the task by
describing two reasons why researchers are interested in developing artificial blood.
The response states that “the artificial blood would always be available and there
would never be a shortage,” and that people “would not have to worry about
impurities or blood diseases in other people’s blood.”
88
Score Point: 2
The student response demonstrates a complete understanding of the task by
describing two reasons why researchers are interested in developing artificial blood.
The response states that “artificial blood would be more safe and wouldnt have any
harmful bacteries” and that it would increase blood supplies because “there is not
enough whole blood in the world for everyone to use.”
89