Unit A Flashcards
What does Ecology mean?
The study of the relationship between living organisms with each other and their environment.
What is the Gaia hypothesis?
“proposes that all organisms and their inorganic surroundings on Earth are closely integrated to form a single and self-regulating complex system, maintaining the conditions for life on the planet.”
What is a Dynamic (changing) Equilibrium (state of balance)?
System with constant change in which the components can adjust to the changes without disturbing the entire system
What is a Biosphere and Biodiversity?
Biosphere:
Where living organisms are found
Biodiversity:
Number of species in an ecosystem. The greater the biodiversity the greater the resiliency of the ecosystem
What does Endangered, Extirpated, Threatened, and Special Concern mean?
Endangered:
close to extinction in all or a significant large area
Extirpated:
no longer exists in one part of the country but found in others
Threatened:
likely to become endangered due to factors
Special Concern:
any species that is at risk because of low or declining numbers in areas of its range
What is an Indicator Species and a Keystone Species?
Indicator Species:
a species sensitive to small changes in environmental conditions. ex: the disappearance of frogs
Keystone Species:
a species that has a disproportionately large effect on the environment relative to its abundance. ex: the gray wolf in Yellow Stone National Park
What are Direct Rays, Indirect Rays, Insolation, Inclination?
Direct Rays:
energy is concentrated and covers less surface area
Indirect Rays:
energy is less concentrated and is spread out over more area
Insolation:
amount of solar energy received by a region’s surface; is dependent on latitude, composition of spheres and earth’s surface
Inclination:
degree by which earth’s poles are tilted from perpendicular
What is an Equinox, Solstices, Orbit, and Rotation?
Equinox:
hemispheres receive equal amounts of day and night (Spring and Fall)
Solstices:
hemisphere receives most hours and least hours of day light (Summer and Winter)
Orbit:
earth travels around the sun (~365 days) Contributes to seasons
Rotation:
earth spins on axis (1 rotation = ~ 24 hours)
What is a Autotroph, Photosynthetic Autotrophs, Chemosynthetic Autotrophs, and Heterotrophs?
Autotrophs: (first trophic level)
“Self Feeders” – produces their own nutrients from radiant energy and abiotic factors
Photosynthetic Autotrophs:
An organism that is capable of using light energy to synthesize sugars from carbon dioxide. Green plants, algae, and cyanobacteria are examples.
Chemosynthetic Autotrophs:
use the energy released by chemical reactions to make a sugar.
Heterotrophs: (2nd, 3rd, 4th trophic levels)
“Other Feeders” – consumes organic molecules from other organisms
What is the difference between a Food Chain and a Food Web?
Food Chain:
A step by step sequence linking organisms that feed on another.
Note: Ecosystems are more complex as organisms depend on several organisms for survival
Food Web:
Interconnecting food chains. Shows the complexity of an ecosystem
Note: Arrows show direction
of energy flow
What are the Laws of Thermodynamics?
First Law:
Energy is neither created nor destroyed but transferred from one form to another.
Second Law:
As energy is transferred it loses thermal energy to the surroundings.
What is an Ecological Pyramid?
Ecological Pyramids:
Represents interaction of trophic levels in an ecosystem
- Loss of Energy
- Growth and metabolism in each tier (thermal energy loss)
- Incomplete digestion of material of previous tier
- Not all matter is consumed from previous tier
What are the different types of Ecological Pyramids?
Pyramid of Numbers:
Measures the number of organisms at each trophic level
Pyramid of Biomass:
Measures the amount of biomass of the organisms at each trophic level
Pyramid of Energy:
Measures the amount of energy at each trophic level
What is Biomagnification / Bioamplification and Bioaccumulation?
Biomagnification / Bioamplification:
The increase in concentration of a substance (pollutant) that occurs in the food chain from one link to the next
Bioaccumulation:
The increase in concentration of a substance (pollutant) in tissues of an organism
