Unit A – Biosphere Flashcards
What is a closed system?
In a closed system, energy can move in and out but matter cannot, therefore all matter has to be recycled, changed, and reused
Is the earth a closed or open system?
The earth is a closed system
What help sustain life on earth?
Incoming solar energy and the cycling of matter
What is the biosphere?
A narrow zone around the earth in which all life exists (10 km below ground level to 30 km above)
What is dynamic equilibrium?
The steady-state of ecosystems; Adjustments are continually made to the ever-changing earth, without disturbing the entire system
Where is 99% of life on earth found?
1 km up and 1 m down
What are the three parts that make up the biosphere?
Atmosphere, lithosphere, hydrosphere
What is the atmosphere?
What is the lithosphere?
What is the hydrosphere?
Air
Land
Water
What are ecologists?
People who study the interactions among living things and the relations they have with their nonliving environment
What does abiotic mean?
What does biotic mean?
Abiotic – nonliving
Biotic – living
What are ecosystems?
Regions of the biosphere wherw biotic and abiotic factors interrelate to the flow of energy and cycling of matter
What is biodiversity?
The number of species in an ecosystem
What is extinction?
What is extirpation?
Extinction is total elimination
Extirpation is when a species is eliminated from a certain area
How is the biosphere maintained?
The biosphere is maintained by a constant flow of energy, originating at the sun
Solar radiation hits the earth, some is absorbed, some is reflected back into space as heat
Why does the earth heat unevenly?
What does this cause?
The earth heats unevenly because of its curvature
This results in weather systems and climatic differences
The sun is at an angle. What happens when you change the angle?
Change the angle and the same amount of radiation is spread out over a larger area (think of a shining flashlight on a ball)
Radiation from the sun strikes the earth at ___°
What does this do?
90°
This delivers much more energy per-unit area and radiation striking the earth at higher latitudes
The earths axis is tilted at ___°
23.5°
Why doesn’t the equator experience seasons?
Because it always receives the same amount of solar radiation
Where does the earth receive energy?
The earths core, tidal energy, the sun
What is albedo?
Degree to which materials reflect solar radiation
Does a lighter color mean higher albedo or lower albedo?
Lighter color – higher albedo
What are the properties of something with higher albedo
Greater reflection and less energy available for organisms
How is albedo represented?
Using a decimal number, telling you the percent of reflected radiation
How is solar energy absorbed?
Absorbed by abiotic components, and eventually reradiating back into space
Absorbed by photosynthetic organisms during photosynthesis
List some facts about photosynthesis
Provides the energy required by the entire system
Stores energy in the chemical bonds of glucose
Carbon dioxide and water and energy turn into glucose and oxygen
List facts about cellular respiration
Releases energy stored in glucose
A process that all organisms must undergo, including plants
Glucose and oxygen turn into carbon dioxide and water and energy
True/false are there organisms that can live in extreme environments at lack sunlight?
True
What are chemoautotrophs?
Chemoautotroph’s are bacteria and producers that use chemosynthesis to produce food
They use carbon dioxide and water and extract chemical energy from certain inorganic compounds
What inorganic compounds do chemoautotrophs use?
H2S
NH3
Fe2+
Sulfur
What can happen if an ecosystems dynamic equilibrium becomes unbalanced?
Species can become threatened or endangered
Habitat can be lost
What is an indicator species?
A species that acts as a warning sign that something is wrong with the ecosystem
What are some causes of imbalance in an ecosystem?
Habitat loss, seasonal changes, climate change, poor air and water quality, increased UV radiation, and introduction of exotic species
Are organisms able to adapt well to changes in their environment?
No, organisms are highly adapted to their environment and are under pressure when there are changes… It can cause extinction or extirpation
How can seasonal changes affect organisms?
Seasonal changes can cause precipitation changes and drastic landscape changes, which displace organisms
What does poor air and water quality result from?
Burning toxic products and fossil fuels, dumping toxins, acid rain, and untreated wastewater emptied into rivers or lakes
What is climate change?
Change in temperature, sunlight, wind, and precipitation
What does an organisms habitat depend on?
The temperature annual amount of precipitation
What is an exotic species?
How may have been introduced?
What are the problems with introducing exotic species
An exotic species is a species not normally found at the habitat
It may have been introduced by wind, animals, or humans
Has no natural predators in its new location, outcompete the native species
What is the first law of thermodynamics?
Give an example
Energy can’t be created or destroyed, it can only change forms
For example solar energy enters the biosphere and is then converted into different forms
What is the second law of thermodynamics?
Give an example
During every energy conversion some energy is lost as heat
For example, during cellular respiration some energy is lost in the form of heat and you use this to maintain your body temperature
What is a food chain?
A step-by-step sequence of who eats who in the biosphere
Describe the order within a food chain
Begin with producers (plants), then first order consumer (herbivores), then second order consumers (carnivores and sometimes omnivores)
Where do producers get energy?
Where do first order consumers get energy?
Where do second-order consumers get energy?
Producers make their own food
First order consumers eat producers
Second order consumers eat first-order consumers
What are trophic levels?
How does energy flow in the tropic levels?
The feeding levels (first, second, third, fourth, etc.)
Energy is transferred from one trophic level to the next one organisms each other
Energy is always lost as heat in each transfer
What are the two types of food chains?
Grazing- Producer eaten by herbivore eaten by carnivore
Detritus/decomposer- Detrius (dead and decaying plant/animal matter) decomposed by decomposers eaten by earthworms eaten by birds
What are food webs?
Food web show the complex feeding patterns of the entire ecosystem and they are more accurate representation of feeding in an ecosystem because they show how organisms are interconnected
What are some limits on energy transfer in trophic levels?
Each time that there is an energy transfer, the amount of energy available in the next trophic level is reduced
Only 10% of the energy is passed on to the next level, the rest is lost as heat
Due to energy loss, fewer animals can be supported as the trophic level increases
What is a pyramid of numbers
A pyramid graph that represents the number of organisms in that environment
It can take on an inverted shapes depending on the relative size of producers to herbivores
What is a pyramid of biomass
A pyramid graph representing the amount of biomass (dry tissue mass)
What is a pyramid of energy
A pyramid graph representing the amount of energy available at each trophic level
Loses one “0” each level up
Is the most accurate representation of a food chain
What are disturbance causing factors in the ecosystem?
- Small-scale changes
- Large-scale changes
- Overhunting/fishing
- Monocultures
- Bioaccumulation
What are small-scale changes in ecosystems?
Seasonal variations, results in less biomass in winter
Example: bird migration, hibernation, lake freezing, tree dormancy
What are large-scale changes in ecosystems?
Permanently changes populations, natural or artificial causes
Example: forest fires, volcanoes, earthquakes
What are the effects of overhunting and fishing on the ecosystem?
Leads to extirpation
Sample: bison
What are the effects of monocultures in ecosystems?
Growing only one type of plant, excluding others, depletes nitrogen and phosphorus in soil
Lots of fertilizer used, excess fertilizer contaminates water systems, less pesticide resistance
What is bioaccumulation in the ecosystem?
Toxins moving up the food chain
List some properties of matter
- Matter must be recycled in the biosphere in order to maintain a steady state
- Matter cannot be created or destroyed
- Matter is cycled in biogeochemical cycles
- Six elements responsible for 95% biomass: Carbon, hydrogen, oxygen, nitrogen, phosphorus, sulfur
What are some properties of water?
Polar molecule, Unique properties to help sustain life, and essential role in global heat balance, moderates climate of nearby land, allows nutrients to be Drawn up into the point, makes up 60% of the cells mass, solvent, supplies hydrogen atoms for photosynthesis, supplies oxygen Adams for cellular respiration
What are the unique properties of water that help it to sustain life?
Why does it have these unique properties?
It has a high specific heat capacity, high surface tension, solid form less dense than liquid, high heat of vaporization fusion, high melting and boiling points
Has these unique properties because of hydrogen bonding
How does water help moderate climate?
Oceans and large lakes moderate climate of nearby land, and regional variations are caused by proximity to large bodies of water
How does water affect nutrients in plants?
The capillary action allows nutrients to be drawn up into the plant from the root system
What is the hydrological cycle?
Movement of water throughout the biosphere
Where is most water stored?
In the ocean and polar ice caps
How does water leave the ecosystem?
Evaporation, transpiration, combustion, cellular respiration, and perspiration
Why does water return to the ecosystem?
What does this do?
A decrease in atmospheric temperature. Returns as precipitation
Water bodies are replenished, land absorbs water, supplying plant roots and replenishing water table
What is percolation?
The movement of a liquid through a porous material
What is leaching?
What Does this do?
Organic matter and minerals at the surface are moved to lower soil layers
Provides nutrients to organisms at lower levels
What are some factors affecting the hydrological cycle?
Deforestation, human consumption, biomagnification, acid deposition
How does deforestation affect the hydrological cycle?
Forests are large holding tanks of water, the roots prevent soil erosion by holding the soil together
Fallen leaves supply nutrients to soil when decomposed
They shade the soil, preventing the evaporation of water
When forests are logged, land becomes nutrient poor, dry, and eventually unusable. Logging displaces organisms
How does human consumption affect the hydrological cycle?
Our consumption of water has increased, so more demand for clean drinking water, and water to be used in industrial processes
How does biomagnification affect the hydrological cycle?
Having metals enter water systems from improper waste disposal. They become stored in the adipose tissues of organisms
How does acid deposition affect the hydrological cycle?
SO2, CO2, and an NOX result from the burning of fossil fuel. These molecules can combine with water in the atmosphere to form acids
These acids return to earth as acid precipitation, which lowers the pH of lakes and ponds, changes pH of the soil
What is the impact of acid precipitation?
Kills fish, soil bacteria, aquatic and terrestrial plants
Increased erosion as rocks degrade
Rusts metal, damage to stonework
Can combine with moisture in your respiratory tract
What is the carbon cycle?
The cycle of matter in which carbon atoms moves from inorganic to organic and back to inorganic
What is the key element for all living organisms?
Carbon
How is carbon dioxide released by?
Burning of fossil fuels, animals and plants during cellular respiration, forest fires, volcanic eruptions
When and why do plants (autotrophs) use this carbon dioxide?
During photosynthesis to make glucose
What is a carbon reservoir?
Carbon storing natural feature that exchanges carbon with other reservoirs
What are the biggest carbon reservoirs?
The atmosphere, oceans, The Earth’s crust
What is dissolved carbon dioxide?
Dissolved carbon dioxide in the ocean is available for plants for photosynthesis
What can be created when dissolved carbon dioxide reacts with water?
CO3 2-
HCO3 -
CaCO3 (if it reacts with calcium)
Where does most of the carbon in oceans end up?
As sediment, forming limestone and sedimentary rock
What has industrialization done to the atmosphere?
Industrialization has meant there’s an increase in burning fossil fuels, increase in population, Less trees to take up carbon emission
What is the greenhouse effect?
Excess carbon dioxide and CH4 inside the atmosphere, warming the earth
How does the greenhouse effect work?
Short wavelength into the atmosphere, objects, are converted into longer wavelengths
Longer wavelengths reradiate back into space
Carbon dioxide prevents the longer wavelengths from escaping, and then reradiates them towards the earths surface resulting in high global temperature
What will be the negative effects of global warming?
An increase in Earth’s average temperature, ice caps melt, melting of permafrost, increase in diseases
Describe the oxygen cycle
Oxygen is produced by plants, taken up by organisms, used up by cells in cellular respiration, found in living organisms, water, the atmosphere, and many rocks
What element is essential to make proteins and nucleic acids?
Nitrogen
What are nitrates?
Usable form of nitrogen for living organisms. Formed by lightning or bacteria in soil
How do plants get nitrogen?
How did humans get nitrogen?
Plants depend on the microorganisms
Humans eat plants or animals
What is denitrification?
Denitrifying bacteria returns nitrogen into the atmosphere
What is nitrogen fixation?
Two processes where atmospheric or dissolved nitrogen is converted into nitrogen ions
What is nitrification?
Nitrifying bacteria convert ammonia into nitrites, then nitrates
What are the two ways nitrogen can leave the system?
Decomposition and denitrification
What is decomposition in reference to the nitrogen cycle?
Bacteria or fungi break down protein in dead organisms into ammonia components. Then nitrifying bacteria can change the ammonia into usable nitrates
What is denitrification in reference to the nitrogen cycle?
Denitrifying bacteria returns nitrogen into the atmosphere. The process speeds up if the soil is acidic, low in oxygen, or waterlogged
What are some problems within the nitrogen cycle?
Fertilizers I did too much nitrogen to the system. Excess nitrogen runs off the fields and into aquatic ecosystems. This causes Algae bloom
What is Algae bloom?
Fertilizers runoff fields and enter the water system. Fertilizer causes rapid Algae growth in water systems. Algae blocks sun for underwater plants. Plants begin to die. As they die, bacteria feed on the remains and bacteria numbers increase. Better use of more oxygen, dissolved oxygen levels decrease. Low dissolved oxygen levels means more dead organisms
What is phosphorous needed for?
Cell membranes, ATP, DNA, and bones
How is phosphorous absorbed and used?
Absorbed groundwater by plants, used by animals
It is the only cycle that doesn’t have __________
An atmospheric component
What kind of cycles are there in the phosphorus cycle?
Two cycles, short and long
What is the short cycle in the phosphorus cycle?
What is the long cycle in the phosphorus cycle?
Biotic, stored in living tissue
Abiotic, trapped in rocks
What kind of environmental effects does phosphorous have?
The same environmental effects as nitrogen
What is ozone depletion?
Destruction of O3 in upper atmosphere
What is nitrate/phosphate pollution?
Adding lots of fertilizer to water systems
