Chapter 46 - Ecology of Ecosystems

Question 1

Define Ecology

Answer 1

the study of interactions between living organisms and their environment, such as competition for limited resources and components of the physical environment

Question 2

What can change an ecosystem?

Answer 2

Disturbances

Question 3

What are the 2 types of Disturbances?

Answer 3

• Natural, cyclic: fire, rain, drought
• Unnatural, anthropogenic (human-caused): deforestation, pollution, burning fossil fuels

Question 4

How can an ecosystem be healthy?

Answer 4

when it’s in equilibrium with all organisms and is in balance with the abiotic and biotic components

Question 5

Ecologists measure what 2 things in response to a disturbance?

Answer 5

• Resistance - the ability to remain in equilibrium despite disturbance
• Resilience - the speed of recovery after a disturbance

Question 6

What is a Food Chain

Answer 6

a linear sequence of energy movement through organisms

Question 7

What makes up a Food Chain?

Answer 7

Primary Producers (photosynthetic organisms) → Primary Consumers (herbivores) → Secondary Consumers (carnivores) → Tertiary Consumers

Question 8

The length of a food chain is limited by what?

Answer 8

energy

Question 9

Energy is ______ as heat at each trophic level, which results in fewer top predators because the amount of energy available is ________.

Answer 9

lost; reduced

Question 10

A ________ model is more descriptive

Answer 10

holistic (food webs)

Question 11

What are the 2 different types of Food Webs?

Answer 11

• Grazing - photosynthetic organisms at the base
• Detrital - decomposers at the base

Question 12

A ________ accounts for all interactions between different species within the ecosystem and is more accurate and descriptive

Answer 12

Food web

Question 13

Ecosystem Dynamics is the study of what?

Answer 13

studies the changes in ecosystems due to disturbances

Question 14

What are the 3 types of Ecosystem Dynamic Models?

Answer 14

• Holistic Model - quantifies competition, interactions, and dynamics of an ecosystem
• Mesocosm Model - partitions off part of the ecosystem
• Microcosm Model - recreates ecosystem

Question 15

What are the 3 types of Ecosystem modeling?

Answer 15

• Conceptual - flow charts to show the interaction between organisms and the environment
• Analytical - uses mathematical formulas to predict how an ecosystem will respond to disturbances
• Simulation - uses complex computer algorithms to model ecosystem

Question 16

Energy is acquired in 3 ways:

Answer 16

• Photosynthesis - solar energy to chemical energy
• Chemosynthesis - inorganic molecules to chemical energy
• Heterotrophy - consuming in order to obtain energy

Question 17

What is Ecosystem Productivity?

Answer 17

the percent of energy entering the ecosystem as biomass at each trophic level

Question 18

What is biomass?

Answer 18

the measurement of living and dead organisms within a trophic level

Question 19

________ bring energy into an ecosystem

Answer 19

primary producers
(gross primary productivity)

Question 20

What is net primary productivity?

Answer 20

the amount of energy available to the next trophic level after accounting for energy requirements of the current level

Question 21

What is Biological Magnification?

Answer 21

the increasing concentration of toxic substances in organisms at each trophic level
Higher trophic level → greater concentration of toxic substances (bioaccumulation)

Question 22

What are the chemicals that make up living organisms cycles through their ecosystem?

Answer 22

• Carbon
• Oxygen
• Hydrogen
• Nitrogen
• Phosphorous
• Sulfur

Question 23

______ and ______ play a role in ______ ______ between biotic and abiotic components

Answer 23

chemistry | geology | nutrient recycling

Question 24

_____% of water on Earth is saltwater
Of the remaining ____%, 99% is unavailable as ____________ and only ____% is available as _______ _______ on the surface of the Earth

Answer 24

97.5%
2.5%
ice or groundwater
1%
liquid water

Question 25

What is one of the most important biogeographical cycles?

Answer 25

hydrologic (water) cycles

Question 26

What 5 processes affect the Earth’s hydrology?

Answer 26

• Evaporation/Sublimation
• Condensation/Precipitation
• Subsurface water flow
• Surface runoff
• Streamflow

Question 27

What are the 2 interconnected carbon sub-cycles?

Answer 27

• Carbon exchange between living organisms
• Carbon cycling through geologic processes

Question 28

How does carbon naturally enters the atmosphere?

Answer 28

through volcanic eruptions and respiration of animals