CONTENT TEST #2 QUESTIONS &
ANSWERS
While researching bacterial growth in 1928, Alexander Fleming observed that the presence of a
specific type of mold resulted in the death of bacterial colonies that came in contact with the
mold. This discovery led directly to which of the following advances? - Answers:the use of
antibiotics such as penicillin for the treatment of infection
As part of a unit about disease prevention, students are learning about how researchers link the
presence of a certain strain of bacteria to the occurrence of a specific disease. Which of the
following is the strongest evidence that a strain of bacterial is the cause of a particular disease? -
Answers:The bacteria can be isolated from all individuals exhibiting disease symptoms but not
from unaffected individuals.
A third grade teacher has developed an activity to support a unit on the water cycle. Stations
representing various components of the water cycle have been set up in different areas of the
classroom. Students will rotate through the different stations and "act out" each of the different
states of water using simple costumes and movements. Which additional action by the students
would most effectively promote their understanding of the water cycle? - Answers:charting their
paths as they move from station to station on a diagram of the water cycle
As shown in the diagram, maple trees produce double seeds with each seed attached to an
elongated flat structure. Which of the following explanations best describes the function of these
specialized structures? - Answers:dispersing the seeds across a large area
A second grade teacher plans to start a vegetable garden to help students learn about the
resources required for plant growth. The teacher uses stakes and string to mark a 5 foot by 5 foot
plot of ground, but determines it would only provide enough space for each student to grow one
plant. In order for each student to have enough space to grow two plants, the teacher plans to
double the area of the first plot. What will be the total area of the enlarged plot? - Answers:50
square feet
Second graders are observing plants and animals present in their school environment as part of a
life sciences unit. Which of the following activities utilizing educational technology would be
most appropriate for strengthening the students' understanding of these organisms? -
, Answers:having students photograph local plants and animals with digital cameras and using the
photos to create a class field guide that describes each organism
Two students have worked together to design a science fair project that examines the effect of
sugar concentration on the respiration rate of baker's yeast. They set up three test tubes, each
containing one tablespoon of yeast taken from the same package. They measure and add the
same amount of filtered apple juice to each test tube. they then add a half teaspoon of sugar to
the first test tube, a whole teaspoon of sugar to the second test tube, and two teaspoons of sugar
to the third test tube. The students know that respiration will produce gas, so they attach a
deflated balloon to the top of each test tube and plan to identify signs of respiration by observing
how long it takes the balloons to inflate enough to Stan erect. Each test tube is placed in the same
sunlit corner of the room to ensure that temperature and light conditions are the same. Which of
the following modifications would significantly increase the - Answers:adding a fourth test tube
containing only yeast and tap water
As part of a unit about matter, a fourth grade teacher provides students with a. recipe for
homemade play dough and sufficient amounts of flour, salt, food coloring, oil, and water to make
a batch of the dough. The teacher then asks students to develop a question that could be used as
the basis to further investigate the properties of the play dough. Which of the following is the
best example of a scientific question that achieves this objective? - Answers:"What happens if
the amount of oil is changed?"
Students are investigating how water affects plant growth. Each students has a total of five bean
seedlings. The seedlings are planted in five separate containers that are placed on a bookshelf
beneath a large window. Plants will be water every Monday, Wednesday, and Friday during a
two week period. During each watering, plant 1 will receive 0.5 mL of water, plant 2 will get 1.0
of water, plant 3- 1.5 water, plant 4-2.0 water, plant 5- no water. At the end of the two week
period, the amount of plant growth will be determined by subtracting the initial height of the
plant from the final height. the students will present the results with a line graph that has
dependent variable on y axis. Which variables should the students plot along the y-axis of their
graph? - Answers:plant height
Elementary school students are learning about the various classes of animals with backbones.
Their teacher also is trying to encourage the students science-reasoning skills. Which of the
following strategies is likely to be most effective in helping students learn to develop arguments
from evidence? - Answers:asking students to make a claim about an animals classification, and
to give the reasons for their assertion
ANSWERS
While researching bacterial growth in 1928, Alexander Fleming observed that the presence of a
specific type of mold resulted in the death of bacterial colonies that came in contact with the
mold. This discovery led directly to which of the following advances? - Answers:the use of
antibiotics such as penicillin for the treatment of infection
As part of a unit about disease prevention, students are learning about how researchers link the
presence of a certain strain of bacteria to the occurrence of a specific disease. Which of the
following is the strongest evidence that a strain of bacterial is the cause of a particular disease? -
Answers:The bacteria can be isolated from all individuals exhibiting disease symptoms but not
from unaffected individuals.
A third grade teacher has developed an activity to support a unit on the water cycle. Stations
representing various components of the water cycle have been set up in different areas of the
classroom. Students will rotate through the different stations and "act out" each of the different
states of water using simple costumes and movements. Which additional action by the students
would most effectively promote their understanding of the water cycle? - Answers:charting their
paths as they move from station to station on a diagram of the water cycle
As shown in the diagram, maple trees produce double seeds with each seed attached to an
elongated flat structure. Which of the following explanations best describes the function of these
specialized structures? - Answers:dispersing the seeds across a large area
A second grade teacher plans to start a vegetable garden to help students learn about the
resources required for plant growth. The teacher uses stakes and string to mark a 5 foot by 5 foot
plot of ground, but determines it would only provide enough space for each student to grow one
plant. In order for each student to have enough space to grow two plants, the teacher plans to
double the area of the first plot. What will be the total area of the enlarged plot? - Answers:50
square feet
Second graders are observing plants and animals present in their school environment as part of a
life sciences unit. Which of the following activities utilizing educational technology would be
most appropriate for strengthening the students' understanding of these organisms? -
, Answers:having students photograph local plants and animals with digital cameras and using the
photos to create a class field guide that describes each organism
Two students have worked together to design a science fair project that examines the effect of
sugar concentration on the respiration rate of baker's yeast. They set up three test tubes, each
containing one tablespoon of yeast taken from the same package. They measure and add the
same amount of filtered apple juice to each test tube. they then add a half teaspoon of sugar to
the first test tube, a whole teaspoon of sugar to the second test tube, and two teaspoons of sugar
to the third test tube. The students know that respiration will produce gas, so they attach a
deflated balloon to the top of each test tube and plan to identify signs of respiration by observing
how long it takes the balloons to inflate enough to Stan erect. Each test tube is placed in the same
sunlit corner of the room to ensure that temperature and light conditions are the same. Which of
the following modifications would significantly increase the - Answers:adding a fourth test tube
containing only yeast and tap water
As part of a unit about matter, a fourth grade teacher provides students with a. recipe for
homemade play dough and sufficient amounts of flour, salt, food coloring, oil, and water to make
a batch of the dough. The teacher then asks students to develop a question that could be used as
the basis to further investigate the properties of the play dough. Which of the following is the
best example of a scientific question that achieves this objective? - Answers:"What happens if
the amount of oil is changed?"
Students are investigating how water affects plant growth. Each students has a total of five bean
seedlings. The seedlings are planted in five separate containers that are placed on a bookshelf
beneath a large window. Plants will be water every Monday, Wednesday, and Friday during a
two week period. During each watering, plant 1 will receive 0.5 mL of water, plant 2 will get 1.0
of water, plant 3- 1.5 water, plant 4-2.0 water, plant 5- no water. At the end of the two week
period, the amount of plant growth will be determined by subtracting the initial height of the
plant from the final height. the students will present the results with a line graph that has
dependent variable on y axis. Which variables should the students plot along the y-axis of their
graph? - Answers:plant height
Elementary school students are learning about the various classes of animals with backbones.
Their teacher also is trying to encourage the students science-reasoning skills. Which of the
following strategies is likely to be most effective in helping students learn to develop arguments
from evidence? - Answers:asking students to make a claim about an animals classification, and
to give the reasons for their assertion
