A camper hiking in the forest observed that
moss and lichen growth was found on the north
side of most forest trees. However, the trees
along a forest stream had moss and lichens on
the side facing the stream, regardless of
compass direction. Which statement BEST
explains the location of growth of moss and
lichens on forest trees?
The body responds to some situations by
releasing blood into the muscles, increasing
heartbeat, and becoming more alert. This
response would be MOST useful to a person
who is
When a person is startled, blood vessels in the
muscles widen, allowing blood to flow away
from the body's organs. This response is
MOST useful because the blood is then able to
Which response to a low blood sugar level
helps the body maintain its internal balance?
Which response to dehydration helps the body
maintain its internal balance?
Which of these stimulates a person to feel
thirsty?
A person's blood sugar level starts to drop
below the normal level. The person will
probably respond by wanting to
These are the distances from the planets to
the sun:
Mercury: 58,000,000 km,
Venus: 110,000,000 km,
Earth: 150,000,000 km,
Mars: 230,000,000 km,
Jupiter: 780,000,000 km,
Saturn: 1,400,000,000 km,
Uranus: 2,900,000,000 km,
Neptune: 4,500,000,000 km,
Pluto: 5,900,000,000 km.
Some students are preparing a report on our
solar system. Which of the following would be
the MOST effective way to present the data
above?
A team of students heated 5 beakers of water,
each to a different temperature. They recorded
the greatest amount of salt that would dissolve
in each beaker. Which of the following would
help the students display the relationship
between temperature and the amount of salt
dissolved?
A student mixed two clear liquids in a beaker,
then covered the beaker and let it sit. White
crystals formed at the bottom of the beaker.
The student concluded that the crystals are a
new substance formed by the two liquids.
Which of the following observations, if made
by the student, MOST strengthen the student's
conclusion?
Some students wanted to compare the usable
energy of several types of energy used in space
heating. The students gathered the following
data:
Passive solar — 5.8 billion BTU (British
Thermal Unit)
Natural gas — 4.9 billion BTU
Oil — 4.5 billion BTU
Active solar — 1.9 billion BTU
Electric heating (coal-fired plant) — 0.4 billion
BTU
Electric heating (nuclear plant) — 0.3 billion
BTU
Which is the MOST effective way for students
to display their data?
A scientist wants to carry out an experiment to
learn how acid rain affects living organisms.
Which of the following would be the BEST
hypothesis to test for this experiment?
Some students riding bicycles coasted down a
large hill. Later in their trip, they coasted down
a small hill. Their speed at the bottom of the
large hill was greater than their speed at the
bottom of the small hill. Which of the
following statements MOST likely explains
why their final speed on the large hill was
greater?
Students measured 500 mL of water into a
plastic beaker that had a tight-fitting lid. They
recorded the mass of the water in the sealed
beaker, and then placed the beaker in the
freezer overnight. They observed that the ice
had a larger volume than the water, but the
mass stayed the same. Which of these is the
BEST explanation of these observations?
Some students were studying the effects of
friction on the motion of objects. They slid a
block down a 1-meter long wooden ramp three
times and recorded the time it took to travel the
length of the ramp. The students repeated the
procedure with the ramp covered with cloth,
and then again with the ramp covered with
carpet. Their data are in the chart below.
Which conclusion MOST completely describes
the results of this experiment?
John hypothesized that dissolving salt into
water produced a chemical reaction because
the salt completely disappeared in the water.
He dissolved 10 g of salt into 500 mL of pure
water. After leaving the beaker in the sunlight
for a few days, the water completely
disappeared, and salt crystals were left in the
bottom of the beaker. Based on this
observation, John knew his hypothesis was
incorrect because
A farm gets all of its water from a well on the
farm. The farmer notices that the water level in
the well is 2 meters lower than at the same time
the year before. Which of the following would
MOST likely explain this change?
A scientist studied 700 children with colds.
One half of the students were given a new cold
medicine. The other half of the children had no
medicine. It took all of the children about 10
days to get over their colds. About 7% of the
children taking the medicine got a mild rash.
About 3% of the children not taking the
medicine got a mild rash.
The information above best supports the
conclusion that the new medicine
probably
The following information is included on a
label for a product containing aloe vera, a plant
extract, that can be swallowed:
Most doctors agree that our brand of freezedried
aloe vera is by far the best form to take
for the best healing benefits. Our research has
shown that our brand is far more scientifically
advanced and has more healing benefits than
any other brand.
Which inference does the advertiser MOST
likely want a person to draw?
Michael Faraday thought that because an
electric current could create a magnetic field, a
magnetic field should be able to create an
electric current. Faraday's research proved his
idea correct and laid the groundwork for the
invention of the —
To demonstrate how limited food supply
affects animal populations, a teacher did an
activity with her class. The teacher used small
paper discs to represent food and the students
represented the animal population. The teacher
took the small discs and placed them around
the room and had the students walk around and
collect them. Any student who gathered five
discs had enough food to eat. The teacher
repeated the activity several times, decreasing
the number of discs each time to show how as
the food supply decreases, it is harder for
animals to find enough food.
Which of the following is a limitation of this
model?
Scientists often study examples in nature when
designing future technology. A scientist studies
bacteria that live near fuel tanks and feed on
materials that are toxic to ocean birds. This
research will MOST likely lead to
A scientist studies how lung cells react to
different human-made chemicals. What the
scientist learns will be MOST helpful
to a
A scientist studies home water use in his
community and graphs the results of his study.
The scientist lives in a community that uses an
aquifer for its water source. To conserve the
most water in private homes, the city council is
MOST likely to pass a law that encourages
people to
A student slides two slabs of clay on a table to
model Earth's tectonic plates. Which of the
following would be hardest to show using this
model?
Solar cells convert energy in sunlight into
electricity. Today, solar cells can be very
expensive. Suppose researchers learn how to
make solar cells that most people can afford to
buy. This research would MOST likely result
in
The production of useful energy from nonuseful
energy is an important part of all human
societies. Which of these types of
transformation of energy was used first by
humans?
Gregor Mendel (1822-1884) is called the father
of genetics. He spent many years crossing
different garden-variety pea plants, until he
was able to predict what type of peas could
grow from a single cross. With which of these
was Mendel probably familiar?
The sun-earth system might be modeled on a
desk-top using a basketball for the sun and a
softball for the earth. A person can move the
softball around the basketball to show how the
earth moves around the sun. Which of the
following is a limit of using a softball to
represent earth in this model?
Long ago people believed Earth was flat.
Which of these would have been the best
observation to use to show the people that this
hypothesis was wrong?
A student is using a balance to measure 50
grams of powdered starch for an experiment.
The student accidentally pours too much starch
from the bottle onto the balance. What should
the student do with the extra starch?
Which of the following data would be MOST
suitable to show in a line graph?
A mixture of powdered sulfur and iron filings
could be MOST easily separated by using a
A group of students is determining the density
of a solid cube of plastic. The MOST
appropriate set of tools for this activity would
be a
Students experimenting with chemical changes
need to measure 15 mL of vinegar. Which
graduated cylinder below contains 15 mL of
vinegar?
Some students are investigating the similarities
and differences between plant and animal cells.
Which of the following sets of equipment
would be MOST useful for this investigation?
Some students are experimenting to test
whether plants need fertilizer for growth. How
should they treat the control plant in this
experiment?
Students must do the following four things
after finishing an experiment. The steps are
shown out of order.
1. Wash beaker
2. Put away unused chemicals
3. Wash hands
4. Wipe off lab bench
Which of the steps should the students do last?
Students use a thermometer to measure the
temperatures of four different types of light
bulbs. Which of these should be used to show
their results?
Which of these is the best way to show the
shapes of the organs of the digestive system?
Which of the following is a major role of genes
found in the nucleus of cells?
Normally, offspring of flies are produced from
fertilized eggs. If the genes in a fly's egg cell
are changed, which of the following is most
likely to happen?
Tridacna clams are found in shallow pools of
the Great Barrier Reef. The clams have a soft
layer of tissue, called the mantle, that opens
outward when the two parts of the clam shell
open. Many different types of algae are living
in the mantle. Since different species of algae
and different amounts of algae live in different
clams, the clams have different mantle color
patterns. The algae help the clam by producing
food for the clams. The clam in turn protects
the algae which is not as exposed to hungry
algae-eating organisms.
Which of the following is most likely an
inherited characteristic of the clam?
Seed banks have been established around the
world to save rare endangered plant species.
The seed banks take up large amounts of room.
What is the smallest part of the seed that could
contain all of the genetic information of the
plant?
Cattle have been kept by humans for many
years. Which of these characteristics in cattle is
most likely to have occurred because ranchers
have used selective breeding?
The sweet potato is a common crop plant found
in most warm areas of the world. The plant
rarely flowers and more rarely makes seeds.
However, the roots and potato vines spread
rapidly, and new plants are easily grown from
the roots and vines of old plants. Some
scientists would like to grow new types of
sweet potatoes that parasites will not attack.
Which of these processes is most difficult in
developing new types of sweet potatoes?