Ch 55 Ecosystem Ecology

Question 1

ecosystem

Answer 1

the sum of all the organisms living in a given area and the abiotic factors with which they interact

Question 2

ecosystems are ____ systems

Answer 2

open

Question 3

autotrophs

Answer 3

an organism that is able to form nutritional organic substances from simple inorganic substances such as carbon dioxide.

Question 4

heterotrophs

Answer 4

an organism deriving its nutritional requirements from complex organic substances

Question 5

heterotrophs are:

Answer 5

consumers

Question 6

primary consumer

Answer 6

herbivore

Question 7

secondary consumer

Answer 7

largely comprised of carnivores that feed on the primary consumers or herbivores

Question 8

tertiary consumer

Answer 8

carnivores that eat other carnivores

Question 9

detritivore

Answer 9

an animal which feeds on dead organic material, especially plant detritus.

Question 10

Only ____ energy is usable as you move up each level

Answer 10

10%

Question 11

biological magnification

Answer 11

the increasing buildup of toxic substances within organisms that happens at each stage of the food chain

Question 12

Carbon is stored in four main reservoirs

Answer 12

1. oceans (the largest reservoir)
2. geological reserves of fossil fuels
3. the terrestrial surface (plants and soil, mainly)
4. the atmosphere

Question 13

Nitrogen is a component of:

Answer 13

Amino acids
Proteins
Nucleic acids

Question 14

Main reservoir of nitrogen

Answer 14

Atmosphere

Question 15

N2 fixed by

Answer 15

bacteria - incorporated into plant biomass

Question 16

Organic matter converted to _____ by bacteria

Answer 16

NH4

Question 17

Some NH4 converted to _____ by bacteria

Answer 17

NO3

Question 18

Inorganic Nitrogen taken up by:

Answer 18

Plants

Question 19

Some NO3 converted back to

Answer 19

N2

Question 20

What mediates the transformations in the N cycle?

Answer 20

Bacteria

Question 21

____ essential to all organisms and ecosystems

Answer 21

Water