AZSCI Systems, Energy, and Matter

Question 1

A scientist is studying the impact of pesticide runoff on a local river. To accurately analyze the effects, which of the following best defines the system under investigation?

Accepted Answer

The river, its surrounding watershed, the pesticides, and the aquatic organisms.

Answer

Only the water in the river.

Answer

The entire state's water supply.

Answer

Just the chemical composition of the pesticides.

Question 2

In a forest ecosystem, energy flows from sunlight to producers, then to primary consumers, and so on. At each transfer, a significant portion of energy is lost as heat. This phenomenon is best explained by which scientific principle?

Accepted Answer

Second Law of Thermodynamics.

Answer

Law of Conservation of Mass.

Answer

First Law of Thermodynamics.

Answer

Principle of uniformitarianism.

Question 3

Which process primarily removes carbon dioxide from the atmosphere and converts it into organic compounds within a terrestrial ecosystem?

Accepted Answer

Photosynthesis.

Answer

Respiration.

Answer

Decomposition.

Answer

Combustion.

Question 4

When 10 grams of magnesium reacts completely with 8 grams of oxygen to form magnesium oxide, what is the total mass of the magnesium oxide produced?

Accepted Answer

Exactly 18 grams.

Answer

Less than 18 grams.

Answer

More than 18 grams.

Answer

It depends on the reaction conditions.

Question 5

Earth is often described as a system that is largely closed with respect to matter but open with respect to energy. What does this statement imply?

Accepted Answer

Earth receives significant energy from the sun but exchanges very little matter with space.

Answer

Both matter and energy freely enter and leave Earth's atmosphere.

Answer

Earth's total energy content remains constant, but its matter changes significantly.

Answer

Matter is continuously created and destroyed on Earth, while energy is recycled.

Question 6

In a predator-prey system, an increase in the prey population often leads to an increase in the predator population, which then causes a decrease in the prey population. This dynamic is an example of a:

Accepted Answer

Negative feedback loop.

Answer

Positive feedback loop.

Answer

Linear progression.

Answer

Isolated system.

Question 7

A solar panel converts sunlight into electricity. This process is an example of:

Accepted Answer

Energy transformation.

Answer

Matter conservation.

Answer

Energy creation.

Answer

Energy destruction.