Chapter 2 - Energy flow and nutrient cycles support life in ecosystems

Question 1

(2.1) What is biomass?

Answer 1

the total mass of living plants, animals, fungi, and bacteria in a given area. Can also refer to the mass of particular types of organic matter such as trees, plant crops, manures, and other organic materials that may be used to manufacture biofuels such as biogas.

Question 2

(2.1) What is energy flow? How does it work?

Answer 2

the flow of energy from an ecosystem to an organism and from one organism to another.

(1) the organism obtains food energy from the ecosystem
(2) the organism contributes energy to the organism

Question 3

(2.1) What are producers?

Answer 3

organisms that produce food in the form of carbohydrates during photosynthesis.
ex. plants

Question 4

(2.1) What are consumers?

Answer 4

organisms that eat other organisms

ex. a bee feeding on a sunflower

Question 5

(2.1) What is decomposition?

Answer 5

the breaking down of organic wastes and dead organisms.

Question 6

(2.1) What is biodegradation?

Answer 6

living organisms such as bacteria breaking down dead organic matter.

Question 7

(2.1) What are decomposers?

Answer 7

organisms that break down wastes and dead organisms and change them into usable nutrients available to other organisms in soil and water.
ex. fungi and bacteria

Question 8

(2.1) What are food chains?

Answer 8

models that show the flow of energy from plant to animal and from animal to animal.

Question 9

(2.1) What are trophic levels?

Answer 9

steps in a food chain. they show the feeding and niche relationships among organisms.

ex. (1) primary producers
(2) primary consumers
(3) secondary consumers
(4) tertiary consumers

Question 10

(2.1) What are primary producers?

Answer 10

organisms in the first trophic level. They are the producers.
ex. plants and algae

Question 11

(2.1) What are primary consumers?

Answer 11

second trophic level. feed on primary producers to obtain energy.
ex. herbivores: grasshoppers

Question 12

(2.1) What are secondary consumers?

Answer 12

third trophic level. feed on primary consumers to obtain energy.
ex. carnivores: frogs and crabs

Question 13

(2.1) What are tertiary consumers?

Answer 13

fourth trophic level. feed on secondary consumers to obtain energy.
ex. top carnivores: hawks and sea otters

Question 14

(2.1) What are detrivores?

Answer 14

consumers that feed at every trophic level, obtaining their energy and nutrients by eating dead organic matter.
ex. earthworms and beetles

Question 15

(2.1) What are herbivores?

Answer 15

primary consumers that eat plants.

Question 16

(2.1) What are carnivores?

Answer 16

secondary consumers that eat primary consumers plans often other secondary consumers. They are often at the tertiary level of a food chain; also known as top carnivores.

Question 17

(2.1) What are omnivores?

Answer 17

consumers that eat both plants and animals.

Question 18

(2.1) What are food webs?

Answer 18

models of the feeding relationships within an ecosystem; formed from interconnected food chains.

Question 19

(2.1) What are food pyramids?

Answer 19

a model that shows the loss of energy from one trophic level to another; often called an ecological pyramid.

Question 20

(2.1) What are ecological pyramids?

Answer 20

food pyramids. There are three types of ecological pyramids: pyramid of biomass, pyramid of numbers, and pyramid energy.

Question 21

(2.2) What are nutrients?

Answer 21

substances such as the chemicals nitrogen and phosphorus that are required by plants and animals for energy, growth, development, repair, or maintenance; important components of nutrient cycles in the biosphere.

Question 22

(2.2) What are stores?

Answer 22

nutrients that are accumulated for short or long periods of time in Earth’s atmosphere, oceans, and land masses.

Question 23

(2.2) What are nutrient cycles?

Answer 23

the way nutrients are cycled in the biosphere; the continuous flows (exchanges) of nutrients in and out of stores.

Question 24

(2.2) What is the carbon cycle?

Answer 24

the nutrient cycle in which carbon is moved through the biosphere; maintains the balance of CO2 in the atmosphere.

Question 25

(2.2) What is the phosphorus cycle?

Answer 25

the nutrient cycle in which phosphorus is moved through the biosphere.

Question 26

(2.2) What is the nitrogen cycle?

Answer 26

the nutrient cycle in which nitrogen is moved through the biosphere.

Question 27

(2.2) What is sedimentation?

Answer 27

the process in which soil particles and decaying organic matter accumulate in layers on the ground or at the bottom of large bodies of water, contributing to the formation of sedimentary rock.

Question 28

(2.2) What is carbonate?

Answer 28

a combination of carbon and oxygen (CO3-2) that is dissolved in ocean water.

Question 29

(2.2) What is photosynthesis?

Answer 29

a process in which carbon dioxide enters the leaves of plants and reacts with water in the presence of sunlight to produce carbohydrates and oxygen; photosynthesis also occurs in some micro-organisms.
energy (sunlight) + 6CO2 + 6H2O => C6H12O6 + 6O2

Question 30

(2.2) What is cellular respiration?

Answer 30

the process in which both plants and animals release carbon dioxide back into the atmosphere by converting carbohydrates and oxygen into carbon dioxide and water.
C6H12O6 (carbohydrates) + 6O2 => 6CO2 + 6H2O + energy

Question 31

(2.2) What is nitrogen fixation?

Answer 31

the process in which nitrogen gas (N2) is converted into compounds that contain nitrate (NO3-) or ammonium (NH4+).

Question 32

(2.2) What are nitrogen-fixing bacteria?

Answer 32

bacteria that convert nitrogen gas (N2) into ammonium (NH4+) during decomposition, playing a significant role in nitrogen fixation.

Question 33

(2.2) What is nitrification?

Answer 33

the process in which ammonium (NH4-) is converted into nitrate (NO3+).

Question 34

(2.2) What is nitrifying bacteria?

Answer 34

soil bacteria involved in two stages of nitrification. In the first stage, certain species convert ammonium (NH4+) into nitrite (NO2-); in the second stage, different species convert nitrite (NO2-) into nitrate (NO3-).

Question 35

(2.2) What is denitrification?

Answer 35

the process in which nitrogen is returned to the atmosphere.

Question 36

(2.2) What are denitrifying bacteria?

Answer 36

bacteria that convert (NO3-) back into nitrogen gas (N2).

Question 37

(2.2) What is leaching?

Answer 37

removal by water of substances that have dissolved in moist soil.

Question 38

(2.2) What is eutrophication?

Answer 38

the process by which excess nutrients in aquatic ecosystems result in

Question 39

(2.2) What is geological uplift?

Answer 39

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