Week #8 Flashcards
What are trophic levels?
Group of organisms which occupy same level in food chain | Each level differs in nutritional relationship with primary energy source
What are autotrophs?
Primary producers | “Self-feeders;”
What are photoautotrophs?
Energy from light
What are chemoautotrophs?
Energy from inorganic molecules
What are heterotrophs?
Consumers | Obtain organic compounds by consuming other organisms
T/F - A Venus fly trap is a heterotroph?
False - A Venus fly trap is considered an autotroph because it primarily gets it food from photosynthesis
What are the types of consumers?
Herbivores, primary carnivores, secondary carnivores, detritivores, decomposers
What are herbivores?
1st consumer level
What are primary carnivores?
Eat herbivores
What are secondary carnivores?
Eat primary carnivores or herbivores
What are detritivores?
Eat decaying matter
What are decomposers?
Microbes that break up dead matter
How are the trophic levels organized?
Primary producers —> primary consumers —> secondary consumers —> tertiary consumers –> decomposer
What are limiting nutrients?
Nutrients in shortest supply and put a limit on growth
What are limiting nutrients for terrestrial and aquatic ecosystems?
Nitrogen and phosphorus
What are limiting nutrients for algal populations in ~1/3 of world’s oceans?
Iron
What is primary productivity?
Synthesis of organic compounds from atmospheric or aqueous carbon dioxide | rate at which energy is stored as biomass (organic material from plants and animals that can be used as a renewable energy source)
What is Gross Primary Productivity (GPP)?
Rate at which primary producers incorporate energy from the sun
What is Net Primary Productivity (NPP)?
Energy that remains in primary producers after respiration and heat loss
About what percent per year of incoming solar radiant energy is captured by primary producers?
~1%/year (in chemical bond energy) | allows respiration to be carried out, some is lost to heat | This is the energy lost in food chains, the energy left after these processes
T/F - Heterotrophs only have chemical-bond energy left in primary producers
True
T/F - Amount of chemical-bond energy decreases as energy is passed from one trophic level to the next
True (think caterpillar and energy lost to feces, cellular respiration, and growth (new biomass)
How much energy is stored as biomass as energy transfers down trophic levels?
10%
T/F - The # of trophic levels is limited by energy availability
True
T/F - The 10% rule is the same as the 1% sun rule
False, 1% is the amount of energy primary producers get from the sun (autotrophs), 10% is the amount of energy passed onto and between consumers (heterotrophs)
