Chapters 1-3

Question 1

Dynamic equilibrium

Answer 1

Any system in which changes are continuously occurring but whose components have the ability to adjust to these changes without disturbing the entire system.

Question 2

What are the 3 basic zones of the biosphere?

Answer 2

Lithosphere (land). Hydrosphere (water). Atmosphere (air).

Question 3

What are biotic and abiotic components.

Answer 3

Biotic- the living components of the biosphere
Abiotic- the non-living components of the biosphere

Question 4

Whats the difference between populations, communities, and ecosystems?

Answer 4

Population is a group of individuals of the SAME SPECIES occupying a given area at a certain time. Community is the population of ALL SPECIES. Ecosystem is the functional unit of the biosphere. Including both biotic and abiotic components.

Question 5

What happens when the dynamic equilibrium becomes unbalanced?

Answer 5

When dynamic equilibrium becomes unbalanced, it can cause harm within the food web of an ecosystem. This will create a domino effect that negatively impacts many organisms within an ecosystem.

Question 6

Degree of risk labels. From least to most.

Answer 6

Special concern (declining numbers), threatened (likely to become endangered, extirpated (no longer exists in one part of the country), endangered (close to extinction in all parts of the country), extinct (no longer exist)

Question 7

Why are frogs an indicator species?

Answer 7

Because they belong to two food chains (land/aquatic). This means that if a change were to impact either food change, there will be a noticeable effect on the ecosystem.

Question 8

What are the 5 trophic levels?

Answer 8

1st (producers/plants), 2nd (PRIMARY), 3rd (SECONDARY), 4th (TERTIARY), apex predators

Question 9

Difference between food webs and chains?

Answer 9

Food chains follow a single path of energy flow through an ecosystem. A food web shows all the different paths of energy flow and multiple items organisms eat.

Question 10

Why do the most biodiverse ecosystems have the most stable food webs?

Answer 10

Biodiversity is important to the stability of food webs because it increases the complexity of interactions between organisms and makes them better able to handle disturbances.

Question 11

Define photosynthesis, cellular respiration, and chemosynthesis

Answer 11

Photosynthesis is the process in which plants use sunlight to synthesize food. Cellular respiration (opposite of Photosynthesis) involves glucose and oxygen as inputs and produces carbon dioxide, water, and energy. Chemosynthesis is the process in which food is made by bacteria or other living things using chemicals as the energy source.

Question 12

What does figure A represent?

Answer 12

Pyramid of energy

Question 13

What does figure C represent?

Answer 13

Pyramid of biomass

Question 14

What does figure B represent?

Answer 14

Pyramid of numbers

Question 15

Approximately how much energy passes from one level of a food chain to the next?

Answer 15

10%

Question 16

How have humans permanently altered ecosystems?

Answer 16

Humans’ use of energy in an ecosystem often changes the ecosystem itself. Most ecosystems can adapt to small changes. However, large-scale changes in ecosystems often permanently change the types and sizes of populations of organisms found in that ecosystem.

Question 17

What is the role of decomposers?

Answer 17

Decomposers break down the organic matter in dead bodies and feces into small inorgainc molecules. These small molecules pass into the soil or water, where they can become part of the living world at some future time.

Question 18

What is a polar molecule?

Answer 18

A molecule that has a positive ans negative end

Question 19

What is a hydrogen bond?

Answer 19

The type of bind that is formed between the positive end of one water molecule and the negative end of another water molecule.

Question 20

What is leaching? And why is it a problem?

Answer 20

As water seeps downward, it carries dossolved orgainic matter and minerals to the lower layers of the soil (leaching). Removing these chemicals from the upper layers of the soil is a serious problem because plants require these nutrients for growth and development.

Question 21

What is acid rain?

Answer 21

When SO² (burning fossil feuls containing sulfer) and nitrous oxides (combustion in vehicles and fossil feul burning plants as well as prosessing of nitrogen fertilizers) enter the atmosphere and combine woth H2O, they form acids that fall onto the earch as acid rain.

Question 22

What are the processes involved in the carbon cycle? How do humans impact the carbon cycle?

Answer 22

Mainly photosynthesis and cellular respiration. Humans emit huge amounts of carbon dioxide during processes including burning of fossil feuls. This means the carbon levels on earth are rapidly increasing.

Question 23

What is the albedo effect

Answer 23

Albedo is an expression of the ability of surfaces to reflect sunlight (heat from the sun). Light-coloured surfaces return a large part of the sunrays back to the atmosphere (high albedo). Dark surfaces absorb the rays from the sun (low albedo).

Question 24

What is nitrogen fixation

Answer 24

nitrogen fixation, any natural or industrial process that causes free nitrogen (N2), which is a relatively inert gas plentiful in air, to combine chemically with other elements to form more-reactive nitrogen compounds such as ammonia, nitrates, or nitrites. (Lightning, bacteria in plants like legumes).

Question 25

What is dentrification?

Answer 25

Opposite of nitrogen fixation. The process where nitrates are converted into nitrites, then into nitrogen gas. Carried out by bacteria that do not require oxygen. Dentrification acts to balance nitrates, nitrites, and atmospheric nitrogen in the soil and completes the nitrogen cycle.

Question 26

What are some drawbacks of fertilizers.

Answer 26

Fertilizers high in nitrogen can cause the soil to become highly acidic because of the high amount of nitrated, causing an increase in nitric acids. High acidity in soil is bad for certain more delicate crops like alfalfa and barley. These fertilizers also pose a problem because of spring runoff. When the runoff from fertilizer rich soil flows into rivers and eventually lakes, the nutrients in the water allow algae to grow more rapidly (algal bloom). Oxygen levels will rapidly decrease due to the decomposition of the dying algae, which in turn kills fish and other organisms, only making the problem worse. High nitrates also pose other problems when introduced to animals and humans through drinking water (attaches to the hemoglobin in blood, reducing its ability to carry oxygen to the tissues)

Question 27

What are the two cycles within the phosphorus cycle?

Answer 27

Long term and short term. Long term involves phosphorus in the earth’s crust. Short term involves living organisms.

Question 28

How do temperature and oxygen levels affect nutrient recycling?

Answer 28

Higher temperatue= increase in rate of recycling. Higher oxygen levels= increase in rate of recycli

Question 29

What is the difference between nitrates and nitrites

Answer 29

nitrates are the usable form for plants. nitrites and stable and are not useful to living organisms.