Environmental Science Mid-term Review
1. Biomes and diversity – Tropical Rain Forest – most diverse biome, biome with the most living organisms.
Desert/Tundra – least diversity due to drastic temperature and low precipitation.
2. Gasses in earth’s atmosphere (N, O, CO2) – Nitrogen (78%) MOST ABUNDANT in the atmosphere. Oxygen (2122%) Humans need for respiration (to breathe). Carbon Dioxide (CO2 – 2%) – Plants use for photosynthesis.
3. Autotrophs, heterotrophs, decomposers, scavengers – Autotrophs – make their own food (ex. Plants – use
sunlight and CO2 to perform photosynthesis). Heterotrophs – need to find/hunt for food. Decomposers – break
down dead things and put nutrients back into the soil. Scavengers – eat dead organisms.
4. Transpiration – The evaporation of water from the leaves of plants.
5. Biological Magnification – the increasing concentration of a pollutant in organisms in higher trophic levels in a
food web. Ex. Mercury in tuna.
6. Population growth
a. Density-dependent – a limiting factor that is dependent of population size. Ex. Lack of food, predation
and disease.
b. Density-independent – a limiting factor that affects the same percentage of a population regardless of
its size. Ex. Natural disasters such as hurricanes and fires.
7. Biotic vs. abiotic factors – Biotic - pertaining to life and living things. Abiotic – non-living things (ex. Sunlight,
water, precipitation, soil).
8. pH of water – pH of water is 7, almost neutral. Called the universal solvent because many things can be
dissolved in water.
9. Carrying capacity (bear hunt/deer hunt) – the number of individuals of a species that can be supported by an
ecosystem. Bear/deer hunt is allowed each year to lower the populations to prevent death by starvation, etc.
10. Predator/prey, competitive exclusion, keystone species (sea star). – Predator is hunter who actively seeks prey.
Prey is eaten by predator. If the predator population goes up the prey population goes down. If the prey
population goes up, the predator population goes up as well. Competitive exclusion – the extinction of a
population due to direct competition with another species for a particular resource in a niche. Keystone species
– a predator that causes a large increase in the diversity of its habitat. Ex. Sea star.
11. Niche – the role of an organism in an ecosystem.
12. Generalized (mouse, cockroaches) vs. specialized species (koala, panda) – Generalized species – a species that
occupies a wide niche (Ex. Mice/cockroaches – have a variety of foods and habitats, can adapt to many different
situations). Specialized species – an organism that occupies a small niche (ex. Giant panda – only eats bamboo,
does not adapt to changes in habitat easily).
13. Extinction and evolution – Species need to either adapt to changes in their habitats/ecosystems or they will die
out, eventually leading to species extinction.
14. Coevolution (milkweed plant/ monarch butterfly and ants/acacia tree) vs. convergent evolution (bees/bats/birds
and dolphin/ichthyosaur) – Coevolution – the process where species interact so closely with one another that
they adapt to one another. Convergent evolution – the independent development of similar adaptations in two
species with similar niches (ex. Bats and birds)
15. Habitat, population, community, ecosystem – Habitat – an environment where a particular species lives.
Population – all members of a particular species that live in the same area. Community – all the populations
that live and interact in the same environment. Ecosystem – all the communities that live in an area together
with the abiotic factors in the environment.
16. Hibernation – dormancy in some animals when the heart rate and breathing slow down, the body temperature
drops, and the animal enters a sleeplike state.
17. Food chains/ food webs/food pyramids (answers listed blow)
a. Energy comes from the sun
b. Producers (autotrophs are the 1st level, plants/photosynthesis)
c. Primary consumers (eat producers)
d. Secondary consumers (eat primary consumers)
e. Tertiary consumers (eat secondary consumers)
f. Trophic levels – (10% energy transfer)
18. Deserts:
a. Climate – temperature and rainfall – less than 10cm of precipitation a year. Drastic changes in
temperature from extreme heat during the day to extreme cold at night – due to lack of
humidity/moisture in the air to keep heat in.
b. Lack of moisture – limiting factor, causes day/night temperature change
c. Pavement – hardened dirt, rocks, minerals
d. Plants with special adaptations to store water (succulents) – ex. Cacti – store water in their spines.
e. Desertification vs. natural desert formation – Desertification – the process of changing semiarid land
into desert as a result of human activity. Can be reversed. Natural desert formation – caused by
changes in precipitation in a region, cannot be reversed.
f. Mountains force rain to the west side and make deserts to the east side – called the “rain shadow
effect” - occurs when warm, moist air cools and loses most of its moisture as precipitation over the
western side of mountainous regions, and the resulting cool, dry air picks up moisture from soil on the
eastern side of the mountains.
19. Legumes – specialized plants that contain a lot of protein (ex. Peanuts, beans, peas).
20. Pesticides – DDT/bald eagles – used to kill pests (usually insects), usually sprayed over a large area. Through
biological magnification pesticide increases in concentration as it is ingested by larger organisms. Caused the
shells of bald eagle eggs to be very fragile and many broke before eagles hatched.
21. Herbivore (eat veggies), carnivore (eat meat), detrivore (eat dead things), omnivore (eats all
22. Habitat destruction, loss of species, extinctions – If enough of a particular type of habitat is destroyed, the
species that live in the habitat can die out completely, or become extinct. When species become extinct,
biodiversity in the ecosystem is reduced.
23. Proteins – need to eat them to get nitrogen to make them
24. Landfills – most common type of waste, NIMBY – Not In My Back Yard – the human population continues to
grow, and garbage production continues to increase. We continue to make more and more garbage, but no one
wants it disposed of In their “back yard”, therefore we are left with the question of where do we dispose of it
25. Biodegradable waste – describes substances that decompose easily and enrich the soil.
26. Toxic chemicals and wastes – an element or molecule that is directly harmful to living things.
27. Superfund Law -
28. Infectious diseases in contaminated water – diseases that are easily passed from one organism to another and
get easily into the water systems, especially where poor water treatment occurs.
29. Eutrophication – the process in which lakes and ponds receive runoff rich in life supporting plant nutrients.
30. Pathogens – a parasite, bacteria, or virus that causes diseases in living things.
31. Mercury – mad hatter, Japan – excessive Mercury was dumped in MInamata bay in Japan. The first sign of the
problem was strange animal behavior. Ingestion of mercury can cause brain, liver, and kidney damage, as well
as coma and even death. The mercury came from a plastics factory that discharged mercury wastes into the
bay.
32. Inorganic vs. organic chemicals – Organic chemicals contain Carbon and came from once living things, inorganic
lack carbon and came from non-living things.
33. Radioactive elements – what are they used for? Why is it hard to get rid of them? – atoms that emit particles
and energy from their nuclei when they decay. They form hazardous wastes that give off radiation that is
harmful to people and other organisms. They are difficult to get rid of because they last very long in the
environment.
34. Thermal pollution – What is it? Where does it happen? Why is it harmful? – a large increase in water
temperature due to human pollution.
35. Politics and pollution – many politicians take a stand on pollution and try to create laws and ways of preventing
further pollution.
36. Clean water act – In response to environmental and political pressure, Congressed passed the Federal Water
Pollution Control Act of 1972. This was an attempt to set water-quality standards for all states. It provides a
vision of water quality standards and a means of measuring improvement.
37. Where do pollutants come from? – humans, factories, industries, etc.
38. Industrial society – a society in which the production of food and other products is performed by machines,
demands large amounts of energy and resources.
39. Ozone – What does it do? What organisms are affected by it? How does it affect humans? – oxygen gas
containing three oxygen atoms per molecule.
40. Ozone layer – why is it good? – Ozone layer prevents UV radiation from reaching earth.
41. CFC’s (chlorofluorocarbons) – a compound of carbon, chlorine, and fluorine once used in refrigerators, air
conditioners, aerosol cans, and in the production of Styrofoam.
42. Hydrocarbons – a compound made only of carbon and hydrogen.
43. Indoor air pollution – What is it? Where does it come from? – Caused by home products such as plastics,
insulation, and cleaners that give off harmful fumes. Air circulation in buildings is often poor, especially during
winter, when buildings are closed up to save energy.
44. Carbon monoxide – silent killer – a dangerous air pollutant. A gas that readily binds with hemoglobin in the
blood. Hemoglobin is the substance in red blood cells that carries oxygen. Carbon monoxide actually binds to
hemoglobin more easily than oxygen does. If carbon monoxide binds to a hemoglobin molecule, the
hemoglobin can no longer carry oxygen. The amount of oxygen carried to all the cells of the body is reduced.
High concentrations of carbon monoxide stress the heart and can cause headaches, dizziness, and even death.
45. 3 Major Air Pollution Problems – Acid precipitation, ozone depletion, global warming.
46. Burning of fossil fuels – releases what chemicals – releases carbon dioxide into the air at alarming rates,
damaging the ozone layer.
47. Acid Rain – precipitation that is more acidic than normal precipitation.
48. Greenhouse Effect – the trapping of radiated heat by gases in the atmosphere.
49. Precipitation – removes particulates
50. Pollution from cars – how to prevent – creation of electric/hybrid cars, more fuel-efficient vehicles.
51. Sound pollution – what decibels are dangerous? 70-80 decibels (dB) are annoying and can lead to hearing loss.
120-130dB can cause physical pain and serious hearing damage.
52. Corrosive wastes – a type of hazardous waste that can eat through steel and many other types of materials.
53.Ignitable wastes – hazardous waste substances that can burst into flames at relatively low temperatures.
53. Medical wastes – hazardous wastes such as old medicines, lab containers, and specimens, some of which are
considered toxic wastes.
54. Reactive wastes – an explosive type of hazardous waste.
55. Radioactive wastes – hazardous waste that give off radiation that is harmful to people and other organisms.
56. Toxic wastes – hazardous wastes made of chemicals that are poisonous to humans.
57. Photochemical smog – a yellow-brown haze that is formed when sunlight reacts with pollutants produced by
cars.
58. Air particulates – a type of air pollutant made of tiny solids suspended in the atmosphere.
59. Ozone layer – layer of the atmosphere that filters out most of the UV radiation given off by the sun.
60. Gaseous pollutants – oxides
61. Carbon dioxide – global warming
62. Predator/Prey relationships – know how to graph
Usually in balance
a. If something happens to decrease predator population – prey population will increase
If something happens to increase predator population – prey population will decrease
b. If something happens to decrease prey population – predator population will decrease
If something happens to increase prey population – predator population will increase