CORRECT ANSWERS
Which of the following characteristics is most important in demonstrating that a hypothesis
should be called a theory?
A. It interprets an observation.
B. It applies to a narrow range of phenomena.
C. It summarizes the most recent work of a scientist.
D. It provides an explanation for the results of many experiments. - CORRECT
ANSWER D.
It provides an explanation for the results of many experiments.
Which of the following should a student select to correctly represent an isotope of K with
mass number 39 and atomic number 19?
A. K with a positive 1 charge, with mass number 39 and atomic number 19
B. K with mass number 40 and atomic number 19
C. K with mass number 39 and atomic number 20
D. K with mass number 40 and atomic number 20 - CORRECT ANSWER B.
K with mass number 40 and atomic number 19 40/19K
Which of the following is a function of mitosis in humans?
A. Synthesis of hormones
B. Production of gametes
C. Repair of damaged tissue
,D. Transmission of electrical signals - CORRECT ANSWER C.
Repair of damaged tissue
n animation of which of the following is most likely to be included in a lesson about how
stars are formed?
A. A cloud of gas contracting and heating up
B. The formation of black holes
C. Meteor showers against a night sky
D. The main asteroid belt orbiting the Sun - CORRECT ANSWER A.
A cloud of gas contracting and heating up
To probe whether students have misconceptions about mass and weight, a teacher asks them
to consider two identical objects, one on the surface of Earth and one on the surface of the
Moon. Which of the following student statements represents a correct understanding about
mass and weight?
A. Both the weight and mass of the object on Earth are greater than the weight and mass of
the object on the Moon.
B. There is no difference between the masses and weights of the objects on Earth and the
Moon.
C. The objects have the same mass, but the object on Earth weighs more than the object on
the Moon.
D. The weights of the objects are equal, but their masses are different. - CORRECT
ANSWER C.
The objects have the same mass, but the object on Earth weighs more than the object on the
Moon
Which of the following pieces of equipment would be most useful in a middle school
classroom activity with the goal of distinguishing the organisms in a drop of pond water?
A. A microscope
,B. A stopwatch
C. A balance
D. A centrifuge - CORRECT ANSWER A.
A microscope
Which of the following best explains how igneous rocks are formed?
A. Rocks are weathered, transported, deposited, and cemented into new rock.
B. Molten material cools and hardens.
C. Rocks are changed by shifting magnetic fields.
D. Rocks are changed by pressure into different kinds of rocks. - CORRECT
ANSWER B.
Molten material cools and hardens.
Which of the following best describes how forces produce tides?
A. Repulsive electrical forces between dissolved ions cause the ocean to increase in volume.
B. Earth's magnetic field exerts an attractive force on the water in the ocean.
C. The Coriolis force pushes water in the ocean toward landmasses.
D. The Moon exerts a gravitational force on the water in the ocean. - CORRECT
ANSWER D.
The Moon exerts a gravitational force on the water in the ocean.
The consequences of which of the following human activities would be the most reasonable
basis for a classroom discussion on the eutrophication of a body of water?
A. Use of fertilizers in agriculture
B. Burning of coal for electricity generation
C. Building of levees for flood control
D. Extraction of oil from shale - CORRECT ANSWER A.
Use of fertilizers in agriculture
, Five breeding pairs of guppies are placed in a large classroom aquarium that contains aquatic
plants, algae, and small invertebrates. The guppies are the only fish in the aquarium and have
plenty of food. If the guppies are given a constant amount of food daily, which of the
following is most likely to happen to the population of guppies in the tank?
A. The population size will remain constant as long as the aquarium is maintained, since the
guppies have enough food to eat.
B. The population size will initially increase rapidly, but eventually the population growth
rate will decrease as the guppies' food is consumed faster than it is replaced.
C. The population size will increase until a mutation results in guppies with different-colored
fins that will outcompete the original fish.
D. The population size will steadily decrease until there are no fish in the aquarium. -
CORRECT ANSWER B.
The population size will initially increase rapidly, but eventually the population growth rate
will decrease as the guppies' food is consumed faster than it is replaced.
The refraction of light underlies the operation of which THREE of the following?
A. A magnifying glass
B. A pair of binoculars
C. An incandescent lightbulb
D. A motion-picture projector - CORRECT ANSWER A. A magnifying glass
B. A pair of binoculars
D. A motion-picture projector
Which of the following statements best describes the heliocentric model?
A. The core of the Sun is composed of helium.
B. Earth and the other planets orbit the Sun.
C. Plants grow toward a source of light.
D. Helium is the most abundant element in the universe. - CORRECT ANSWER B.