Unit 2 Quiz 1 Flashcards
everything after unit 1 till Chapter 6 succession slides
Define producers/autotrophs
organisms that can convert inorganic substances to nutrition/energy, providing organic substances
Describe the process by which producers convert solar energy into chemical energy and how the energy is accessed and utilized by most plants
photosynthesis
cellular respiration
Define consumers/heterotrophs
an organism that obtains its nutritional requirements through consumption of complex organic substances
Understand primary, secondary, and tertiary consumers
primary consumes producers
secondary consumes primary
tertiary consumes secondary
etc.
Trophic level?
the position an organism occupies on a food web
Food web vs. food chain
why are food webs important
Chain: linear pathway of energy transfer
web: interconnected food chains
webs allow scientists to understand how a change in 1 species can affect others
scavenger?
animal that feeds on dead animals or decaying OM
detritivore?
animal that feeds on dead OM, in particular plant detritus
decomposer?
breaks down OM into simpler substances
Ecology Definition
Study of interactions between organisms and their environment (Abiotic and biotic)
Ecosystem:
area distinguished by a particular mix of biotic and abiotic factors. Can have a wide variety of scales
Ecosystem ecology:
studies flow of energy and matter within and between ecosystems
What is Gross Primary product? What is net primary productivity? Ecological significance of NPP?
GPP is total energy captured through photosynthesizer in an ecosystem. NPP is the remaining energy after producer cellular respiration.
GPP - respiration = NPP
NPP is significant because it is the energy available to contribute to the biomass of producers, and therefore the energy available to consumers
What happens to energy as it moves through food web?
Rule of 10?
consumers must expend energy for various reasons. Some energy will also be lost as heat whenever energy transformations take place.
Only about 10% of energy contained in prey a predator consumes contributes to biomass
3 steps to flows of matter:
- producers use resources to produce biomass
- matter moves through biotic components of ecosystem through consumption and use
- ultimately all of this matter is recycled by detritovores and decomposes
distinguish between detritovores and decomposers, give examples
detritovore: mechanically break down OM. Examples are worms or soil insects
decomposer: chemically break down OM like bacteria or fungi
Biosphere:
sum of all ecosystems; largest level of biological organization
Reservoirs vs. Flows:
Reservoirs: components that contain matter in an ecosystem (water, air, OM)
Flows: processes that move matter between reservoirs
WATER CYCLE
-Reservoirs?
-Flows?
know general idea
anthropogenic impacts?
-reservoirs: bodies of water, soil, plants, atmosphere, ice and snow
-flows: evaporation & evapotranspiration, condensation/precipitation, runoff, and melting
Glacier, ice caps, and snow pack release water very slowly allowing for greater soil uptake. Global warming is accelerating this and this causes soil to become saturated and runoff to build up, causing flow into ocean. This decreases our freshwater availability and contributes to sea level rise.
CARBON CYCLE
-Reservoirs?
-Flows?
Explain an image of it
Anthropogenic impacts?
-reservoirs: atmosphere (CO2), Bodies of water (Dissolved CO2) ,living things, soil and ocean floor (OM), and earth’s crust (hydrocarbons/fossil fuels)
-flows: Exchange between bodies of water and atmosphere, photosynthesis/carbon fixation, respiration, burial and sedimentation, extraction & combustion
-Human activities are disrupting long term sinks of carbon and returning it to the atmosphere. Leads to global warming & ocean acidification
NITROGEN CYCLE
-Nitrogen tends to be a ___ nutrient. Explain
-What is nitrogen fixation?
-What do nitrogen fixing bacteria do with plants?
-What do nitrifying bacteria do?
-Once N is available to plants…
- Under anaerobic conditions bacteria ____
-anthropogenic impacts?
-limiting nutrient. This means that organisms require a large amount of this to grow
-Nitrogen fixation is a process by which N2 in atm is converted to a usable form via natural or synthetic abiotic processes, and mostly biologically
-Nitrogen fixing bacteria form symbiotic relationships with certain plants and exchange N for sugars
-Nitrifying bacteria in soil convert fixed nitrogen and other nitrogen forms into nitrate, which is easily accessed by plants.
-Once plants have it N cycles through trophic levels and is returned to environment (N assimilation & mineralization)
-under those conditions denitrifying bacteria return fixed N to atm as N2
-excess N in soil form fertilizers moves into waterways via runoff and leaching (Groundwater) which contributes to eutrophication (too many nutrients) an algal blooms can result
PHOSPHOROUS CYCLE
-P is also a ____ nutrient which means…
-The P cycle is usually __
-Describe __ parts of phosphorous cycle
-Anthropogenic impacts
-limiting
-slow. Releases via weathering (and now mining)
-STEPS
1. P released from weathering of applied as fertilizer is either taken up by producers and cycles through food web or enters waterways. All will enter waterway eventually.
2. phosphorous cycles through food web and is slowly returning to ocean
3. P deposits in ocean floor and can be incorporated into sedimentary rock
4. geologic cycles return rock to surface (hence why it is slow)
-impacts are similar to N cycle. Eutrophication can occur.
What is an ecological disturbance?
Examples?
a temporary change in environmental conditions that causes significant change in an ecosystem
Examples in nature are droughts, fires, blizzards, etc.
Examples from people are development, invasive species, air pollution, etc.
Anthropogenic effects on natural disturbances
people tend to influence severity, frequency, and duration of these disturbances.