Earth Systems and Cycles

Question 1

What is an isolated system?

Answer 1

A system that does not exchange energy or matter with its surroundings. Not very common.

Question 2

What is a closed system?

Answer 2

A system where there is an exchange of energy but not mass (like a food cooler).

Question 3

What is an open system.

Answer 3

A system that has both the exchange of energy and mass (water cycle).

Question 4

What is feedback?

Answer 4

It is when there is a change in one part of the system which causes a change in another part of the system.

Question 5

What is a positive feedback loop? Give an example.

Answer 5

A loop in which a part of the system increases, leading to an increase in another part. Example would be temperature rising, causing ice to melt, leading the ocean to absorb more heat.

Question 6

What is a negative feedback loop? Give an example.

Answer 6

When there is an increase/decrease in one part of the system leading to an increase/decrease in another part of the system. Opposites. An example would be Lokta-Volterra- predator populations rise and prey population fall, leading to a decrease in prey food.

Question 7

What is the term used to describe a system balanced over time?

Answer 7

Steady State Equilibrium

Question 8

What is the term used to describe a system that fluctuates around an average?

Answer 8

Dynamic Equilibrium

Question 9

What is an ecological threshold?

Answer 9

The point at which a relatively small change or disturbance in external conditions causes a rapid change in an ecosystem.

Question 10

What happens when an ecological threshold has been passed?

Answer 10

The ecosystem can no longer return to the original threshold and reaches metastable equilibrium.

Question 11

What are the 5 threshold components?

Answer 11

1. Triggers
2. Structural Category
3. Species Loss Category
4. Functional Category
5. Property Extinction Category

Question 12

What is the 1st law of Thermodynamics?

Answer 12

Energy cannot be created or destroyed, only transformed.

Question 13

What is the 2nd law of Thermodynamics?

Answer 13

When energy is converted form one form to another, quality declines as entropy increases.

Question 14

What is a complex system? Give an example.

Answer 14

Any system including a large number of interacting components. Ex. Global climate

Question 15

What are the 5 different components of Earth?

Answer 15

1. Lithosphere
2. Biosphere
3. Atmosphere
4. Hydrosphere
5. Cryosphere

Question 16

Between 1968 and 2005, what percentage of wetland has been redacted?

Answer 16

21%

Question 17

Between 1968 and 2005, what percentage of wetland basins have been lost or degrated?

Answer 17

69%

Question 18

What is a scientific Experiment?

Answer 18

An organized and detailed series of steps to validate or reject a hypothesis.

Question 19

What is the Precautionary Principle?

Answer 19

Where there are threats of serious or irreversible damage, lack of full scientific certainty shall not be used as a reason for postponing cost-effective measure to prevent environmental degradation.