Ecology Test 1 Chapter 25 Flashcards
What is a food chain?
a linear depiction of energy flow with each organism feeding on and deriving energy from the preceding organism
What is a trophic level?
each feeding level in the chain
What are autotrophs and some examples of it?
they harvest light or chemical energy and store that energy in carbon compounds; plants, algae, and photosynthetic prokaryotes use sunlight for this process
What are primary producers?
form the base of the food chain, they produce the energy rich tissue upon which nearly all other organisms depend
What are heterotrophs?
organisms in trophic level above the primary producers, they receive their nutrition by eating other organisms
What are primary consumers?
organisms that obtain their food by consuming primary producers; many animals, most protist, and some plants
What are herbivores?
Organisms that eat plants and algae; some primary consumers like those that ear chemosynthetic organisms around black smokers are not herbivores
What are secondary consumers/carnivores?
Organisms that eat primary consumers that feed on the tissues of other organisms
What are tertiary consumers?
Organisms that feed on secondary consumers
What is detritus?
unconsumed plants die and decompose in place, this material along with animal waste products and remains
What are detritivores?
Consumers that get their energy from detritus break down organisms and fecal matter from all trophic levels
What is a food web?
draw relationships between these plants and animals not as a simple chain but more elaborate interwoven
What is a connectedness webs?
all known links are drawn and equal importance is attached to each link
What is an energy web?
where interaction strengths based on quantities of food consumed are indicated by the thickness of connecting links
What is a functional web?
One that identifies the most important feeding relationships
3 types of food webs
connectedness, energy, and functional food webs
What is trophic-level transfer efficiency?
the final measure of efficiency of consumers as energy transformers which is the amount of energy at one trophic level that is acquired by the trophic level above and incorporated into biomass
What is the pyramid of numbers ?
the number of individuals decreases at each trophic level, with a large number of individuals at the base and fewer individuals at the top
What is a pyramid of biomass?
one way to reconcile such exceptions is to weigh the organisms in each trophic level, usually measured as dry biomass
What is a standing crop?
the total biomass in an ecosystem at any one point in time, processes large amounts of energy
What is the pyramid of energy?
shows energy production rather than standing crop, is never inverted
What is linkage density?
another measure of food web complexity which is the number of links per species
What is a keystone species?
a species within a community that has a role out of proportion to its abundance
What is a dominant species?
one that has a large effect in a community because of its abundance or large biomass
What are umbrella species?
species whose habitat requirements are so large that protecting them would protect many other species existing in the same food web or habitat
What is a flagship species?
a single large or instantly recognizable species
Which of these organisms is a heterotroph?
Diatom, moss oak tree, corn plant, fish
Moss
Lions normally feed at which trophic level?
2
If there are 20 species in a food web, the potential number of links is?
190
If there are 20 species and 20 links in a food web the actual connectance is?
0.026
If there are 20 species and 40 links in a food web the linkage density?
20
Chemoautotrophic bacteria are?
Tertiary consumers
A species that has an effect out of all proportions to its commonness is called a?
Umbrella species
If production at trophic level n is 50 kcal/m^2 and production at trophic level n - 1 400 kcal/m^2 then trophic level transfer efficiency is?
20%
Which of the following organisms is not a keystone species?
Distemper virus
Polar bears are often though of as a(n) _______ species?
Invasive
