Chapter 59 & 60 Flashcards
(28 cards)
The species in an ecosystem are divided into ___ ___. They are different feeding levels.
trophic levels
The species that are at the base trophic level, the level that supports all others, are called ___ ___.
primary producers
Primary producers are usually ___ organisms such as plants or phytoplankton. Primary producers can also be ___.
photosynthetic
chemosynthetic
The next trophic level above that of primary producer consists of heterotrophs such as herbivorous animals, these organisms are called ___ ___
primary consumers
The next trophic level above primary consumer contains carnivores and these organisms are called ___ ___
secondary consumers
There can be ___ and ___ consumers as well.
tertiary
quaternary
The various trophic levels starting with primary producers form a ___ ___
food chain
Most ecosystems are quite complex and are called ___ ___
food webs
the total amount of light energy converted into chemical energy in a certain time period
Primary productivity
total primary productivity
Gross primary productivity
equal to the gross primary productivity minus the energy used by the producer for respiration
-50%-90% of gross primary productivity
Net primary productivity
Primary productivity is often expressed as ___ (weight) of vegetation (or other producers) added to the ecosystem per unit area per unit time.
-Typically g/m2/year
biomass
___ ___ is the rate consumers convert the chemical energy in their food into their own new biomass. Much energy is lost during the incorporation of the energy from food into a consumer’s biomass.
Secondary productivity
___ ___ is the percentage of energy transferred from one trophic level to another. This is usually highly variable.
Ecological efficiency
shows the loss of energy in a food chain
Pyramid of productivity
abundance of species at each trophic level
Pyramid of numbers
___ are cycled through an ecosystem. There are water cycles, carbon cycles, nitrogen cycles, phosphorus cycles, and other cycles.
Chemicals
biochemical cycles
___ lakes are filled with algae or aquatic plants. The abundance of algae or plants is often caused by fertilizer or sewage runoff. ___ and ___ are key nutrients contributing to these conditions.
Eutrophic
phosphorous
nitrogen
___ ___ study and are involved in preserving ___.
Conservation biologists
biodiversity
___ is the diversity of species found in an ecosystem.
Biodiversity
We are now in the midst of a ___ ___, a mass extinction event of our own doing. Threats to biodiversity include ___ destruction, ___, and competition from ___ ___.
biodiversity crisis
habitat
over-exploitation
exotic species
areas that contain unique species
Biodiversity hot spots
the smallest number of individuals needed to maintain a population
Minimum viable population size
the amount of habitat needed to maintain a population
Minimum dynamic area
