Ecosystems and Conservation Flashcards
what is an ecosystem?
community + abiotic factors
1st law of thermodynamics
The Conservation of Energy
Energy cannot be created or destroyed, but only transferred or transformed
2nd law of thermodynnamics
Every exchange of energy in an isolated system increases the entropy of the universe
not all energy can be used/some energy becomes unavailable to do work and is often lost as heat
what is entropy?
a measure of disorder
Law of the conservation of matter
matter cannot be created or destroyed
what is matter?
anything that has mass and occupies volume
diff between energy and matter?
energy cannot be recycled, but matter/chemical elements are continually recycled
what is the ultimate driving energy source for most ecosystems?
solar radiation/ the sun
what are primary producers usually?
photosynthetic organisms that convert solar energy into chemical energy (used to make ATP)
where is the chemical energy made by primary producers stored?
bonds of sugars and other organic compounds
when are the sugars and organic compounds broken down?
in cellular respiration to fuel an organism’s metabolic needs such as growth
what are metabolic needs?
the sum of all chemical reactions in the body/ making and breaking of molecules
photosynthesis equation
6 CO2 + 6H2O + light energy —> C6H12O6 + 6O2
cellular respiration equation
6O2 + C6H12O6 —> 6 CO2 + 6H2O + 36 ATP
why is the “Blood Falls” glacier in Antarctica red? what are the bacteria in this example?
Bacteria that live off of sulfur compounds and iron-containing ions live there. The color is from Fe being oxidized
chemo autotrophs
what do all trophic levels depend (directly or indirectly)
primary producers - set budget for the entire ecosystem
name the term for all the teeth in mouth
incisors, canine/cuspid, premolar/bicuspids, 1st 2nd 3rd molars, wisdom tooth
how many teeth do adults have?
32 teeth
what do decomposers like bacteria and fungi secrete?
enzymes onto their food source/ substrate to digest and absorb the broken down products
what do decomposers play a critical role in?
recycling elements back for the primary producers
what is the name of the interwoven mat of the thread-like structures that fungi (like mushrooms) secrete from?
mycelium
what are the 4 most common elements of life?
CHON - carbon, hydrogen, oxygen, nitrogen
what are the 6 most common elements of life?
SPONCH - sulfur, phosphorus
We are not mostly SPONCH…what are we?
CaPONCH
for sake of simplicity, we didn’t include Ca as it’s an ionic bond
what molecule are humans primarily?
h20
what is gross primary productivity?
the amount of energy from light (or chemicals w chemoautotrophic systems) converted to chemical energy stored in organic molecules
net primary productivity
GPP minus the need of the primary producers to fuel their own energy needs for cellular respiration
what is available to be used by the ecosystem
often expressed as the amount of biomass added to an area over time
based on this graph, how does deforestation impact reflectance and climate chnage?
decrease vegetation=increase heat absorbance=increase global warming
which terrestrial biome has the greatest NPP?
rainforest
why do tropical forests have nutrient-poor topsoil?
due to immense biomass and vertical stratification, each layer has a high demand for nutrients
rapid recycling/decomposition is speed up which leads to poor soil
deforestation causes land to dry up and fewer nutrients are in the soil and increases erosion
why are nutrients in soil also a limiting factor?
they control a population’s growth and often must be added for increase increased primary productivity in terrestrail ecosystem
how does nitrogen and phosphorus affect plants?
N- limits plant growth
P - in older soils, phosphates are leached away by water
H2O, freshwater vs saltwater components
freshwater - limited amounts of PO4-3
saltwater - limited amounts of NO3-
what evolved mechanisms do plants have involving the uptake of limiting nutrients?
increase uptake; legume plants have a mutualistic relationship with nitrogen-fixing bacteria that live on their roots called Rhizobia
where do Rhizobia live?
nodules on legume plants
another mutualistic example of plant roots?
plant roots have mycorrhizae which is a fungus that supplies phosphate to the plants
how can we measure an animal’s efficiency at transforming energy?
production efficiency = net secondary production X 100%
——————————————–
Assimilation of primary production
what is net secondary production?
energy stored in the organism for growth and reproduction
birds and mammals typically have production efficiencies in the 1-3%, while fish have 10%?
warm blooded (endotherms) and takes a lot of cellular respiration making ATP to make constant body temp
what is trophic efficiency?
energy transferred to an entire trophic or feeding level in a food chain
explain how a biomass pyramid can be inverted?
when phytoplankton grow, reproduce, and get consumed quickly by the zooplankton/ they have a short turnover/generation time
eating what is an inefficient way of tapping into photosynthetic production?
eating meat
how could agriculture feed more people if we were what?
primary consumers
what are biogeochemical cycles?
life, earth, molecules cycles including both biotic and abiotic components
which mineral reservoirs cannot be involved in nutrient cycling?
minerals in rocks and in fossil fuels
what living organism was coal before when it was alive?
vegetation in swamps
what living organism was oil?
Protoplankton
why are fossil fuels so energy rich?
c-c and c-h bonds
what does percolation mean?
filter the way through porous material (soil)
what is transpiration?
water loss through leaves (stomata)
what is evapotranspiration?
what loss from the landscape
describe what ground water looks like?
water in porous/saturated sand/gravel
what do humans burn that releases co2 into the atmosphere?
fossil fuels and wood
through what process do plants and other autotrophs take in CO2?
photosynthesis
through what process do plants animals, and all aerobic organisms release CO2?
cellular respiration
do autotrophs do photosynthesis, cellular respiration, or both?
both
do plants have chloroplast, mitochondria, or both?
both
what inorganic form in the phosphorus cycle found in?
PO4-3
why does all life on Earth require phosphorus?
nucleic acids
cells have phospholipid bilayer
ATP
builds strong bones and teeth
since phosphate is a solid, how is it released from rocks?
weathering and geologic uplift
how do plants obtain phosphate?
absorbs from soil
how do animals obtain phosphate?
eat plants or eat animals
looking at the nitrogen cycle, what gaseous form does it travel around the atmosphere?
N2 (g) ~ 80% of atmosphere
how does nitrogen fixation occur? what is is
pulling N2 gas from the atmosphere
legumes, lightening, free living soil bacteria
what human practices releases a lot of nitrogen onto land and cause eutrophication?
fertilizers, sewage, factory farms
what is the process called of returning N2 gas back into the atmosphere?
denitrification
why does all life on earth require nitrogen?
amino acids
nucleic acids- nitrogenous bases
in the nitrogen cycle, what do nitrogen fixation? (3)
lightning
free-living nitrogen-fixing soil bacteria
rhizobia bacteria
if soil is acidic, what happens in the nitrogen cycle?
it releases protons, so N2 is converted into ammonia NH3
what does living soil bacteria do to NH3?
uses enzymes to convert NH3 into ammonium NH4+
what is the process of creating NH3 or NH4+
ammonification
what do free living nitrifying bacteria do to ammonium?
converts NH4+ to nitrite NO2-
what does free living nitrifying soil bacteria convert nitrite to?
nitrate NO3-
what is the process of creating NO2- or NO3- called?
nitrification
what two compounds can app plants assimilate/use?
ammonium and nitrate
how do decomposers contribute to ammonification?
break down waste and dead back into ammonium
what is bioremediation?
involves using organisms like bacteria, fungi, plants to detoxify and restore polluted ecosystems
fungus uses enzymes to degrade plastic in anaerobic environment
what is causing mass extinction?
anthropogenic activities
how many species are discovered? yet to be discovered?
2 million; 10-100 million more
what is conservation biology?
seeks to sustain ecosystems and preserve biodiversity
why is preserving genetic diversity important?
genetic variation enables evolutionary responses to environment change
benefits of preserving threatened and endangered species (3)
food, fiber, medicine
rosy periwinkle of madagascar benefit
contains alkaloids that inhibit cell growth
EO Wilsom reason to care for preserving biodiversity
biophilia - “life” “love”
belief that other species are entitled to life and we are all connected to nature
what is habitat fragmentation? what does it do? (3)
development causing organisms to live in small patch
threats to biodiversity as it causes habitat loss
leads to inbreeding, lowers genetic variation
solution to habitat fragmentation?
movement corridors to connect isolated patches that allow for gene flow
what is the threat of overharvesting?
overharvesting animals at a rate that exceeds the ability of the species to rebound causes that population to decline
what is a global change threat?
acid precipitation - rain, snow, sleet, or fog with a pH of less than 5.2
how does burning wood and fossil fuels add to acid precipitation?
it releases N and S which react with H2O to form acids like sulfuric acid (H2SO4) and nitric acid (HNO3)
what are some negative consequences of acidic precipitation?
development of eggs in spring (fish and frogs) decline, trees growth stunted, seed germination decline
when US burns fossil fuels, which neighboring country is most affected due to winds?
Canada
show reaction for sulfurous acid (H2SO3)
SO2 + H20 = H2SO3
what does lake michigan have that lessens the effects of acidic precipitation?
limestone (CaCO3) which is alkaline, so it helps buffer the acidic precipitation
what is alkaline mean?
basic
limestone buffer equation
CaCO3 + H2SO4 —-> CaSO4+H2CO3 —> H2O + CO2
what is limestone comprised of? what is it turned into when it is put under greater pressure for more time?
mostly shells; marble
what is biological magnification?
when toxic chemicals become more concentrated in successive trophic levels of a food web
different names from biological magnification? (2)
biomagnification; bioaccumulation
whose book brought attention to biomagnification? of what pesticide?
Rachel Carson’s Silent Spring; DDT - used to control mosquitos
How did Carson describe the accumulation of DDT?
makes its way up the food chain and affects the high-level carnivores the most
it accumulates in the fat tissues and interfers with calcium in eggshells
how did DDT affect eagles?
weight of parent incubating eggs broke the shells
is DDT banned?
in US, but tropics still use to control mosquito to stop spread malaria
What is PCB? What were they used in?
chlorinated hydrocarbon; coolants, electrical insulation - now banned
why are herring gulls the most affected by PCB?
eat mainly lake trout and smelts which have a high amount of PCB
how does PCB affect the body?
endocrine system (hormones) - more imitation estrogen=more chances of getting breat cancer
how does PCB affect the body?
endocrine system (hormones) - more imitation estrogen=higher chance of breast cancer
what is another example of biomagnification? how is it made?
mercury; by-product of plastic production and coal-fired power generation
how does mercury accumulate in fish?
it gets into rivers and the sea and it is picked up by bacteria that covert it into an extremely toxic water-soluble compound (methylmercury CH3HG+)
effects of mercury poisoning in humans?
neurological symptoms - numbness, muscle weakness, hearing, vision, speech problems, insanity, paralysis, coma, and death
why were English people in the hat making industry in the 18th and 19th centuries going insane/developing dementia?
mercury was used in the felt tophats and absorbs through the skin
does having mercury filling dental fillings negatively affect one’s health?
CDC says no evidence that people with amalgams have compromised health
what is the ozone layer (O3)
layer in the stratosphere that protects life on Earth from UV radiation
what has happened to the ozone?
satellite images show that springtime (Sept-Dec) ozone thinned over Antarctica since the 1970s
how large does the hole get in the ozone?
3 times the size of US
Increased UV radiation leads to DNA damage, what else?
melanoma
cataracts
what is thinning the ozone layer?
CFC - chloroflurocarbons
what are CFCs?
used in air conditioning and refrigerators. Styrofoam, aerosol cans
are CFCs produced in the US today?
no, but they will continue to react for the next 50 years
what part of the CFCs does the most damage to the ozone layer?
Chlorine
what do CFCs turn O3 into?
O2
what is sustainable develpoment?
involves meeting the needs of people today without limiting the ability of the future generations to meet their needs
what soes systaibable develpoment involve?
developing, managing, and conserving Earth’s resources as responsibly as possible
