Bio 112 – Exam 1 Review
Introduction – Environmental science (8 questions)
Definition and scope of Environmental Science
Scientific assessment of environmental problems involves:
1) The Process of Science (see Fig. 1.13; Table 1.2)
Observations —> Questions
Hypothesis formation and testing (experiments, etc)
Reproducibility (replication of tests)
Report/Publish Conclusions (Accept or Reject Hypothesis – Never proven as true!)
2) Evaluation of Data —> Statistics (see “Exploring Science;” page 15)
3) Critical thinking has different components/aspects:
Analytical thinking (or) Logical thinking (or) Creative thinking (or) Reflective thinking
4) Inductive Reasoning: Collecting specific facts/observations lead to formulation of a general rule or model
5) Deductive Reasoning: Using a general rule or model to explain or predict specific conditions
4) Predictions & Theories —> Explanations & Paradigms
Scientific Consensus —> Solution to Problems <Versus> Pseudoscience & Baloney detection (Table 1.3)
History of Environmentalism & Environmental Science:
Resource conservation:
G.P. Marsh —> T. Roosevelt —> G. Pinchot (1864 – 1900s)
Nature preservation:
John Muir & Stephen Mather (1900s)
Environmental science leads to environmental movement:
Rachel Carson (“Silent Spring” – 1962)
Response to global environmental issues (Since 1980s)
United Nations:
Earth Summit (Sustainable Development/Biodiversity); Montreal (Ozone Depletion); Kyoto (Global warming)
Current Environmental Conditions & Issues <—> Human Development
Root causes:
Exponential human population growth
Finite Earth Capital
Developed vs. Developing Countries —> inequalities, issues (Know Table 1.1!)
Consumption & Sustainability
Each Day an American consumes 40 lbs of fossil fuels, 30 lbs of metals/minerals, 25 lbs of food,
20 lbs of wood, and 100+ gal of water
Environmental impacts determined by:
1) population size, 2) per capita resource use, & 3) environmental impact of resource use
Indigenous people as guardians of biodiversity
Text Coverage: Chapter 1 (all)
Ecology – General Intro & Ecosystems (10 questions)
Definition and scope of Ecology and ecological systems (p 28 & notes)
Ecological Hierarchy:
Organism —> Population —> Community —> Ecosystem —> Biosphere
System behavior
Definition and scope of Environment
(abiotic & biotic environment, compare/contrast with habitat & climate)
1) Energy Flow in Ecosystems (Fig 2.17 better than 2.15 – why?)
(Review: Kinetic & Potential Energy / 1st & 2nd Laws of Thermodynamics; p 33-35)
Primary Production comes from photosynthesis (converts electromagnetic energy to chemical bond energy)
6.H20 + 6.CO2 + sunlight –––> C6H12O6 + 6.O2
Trophic Structure of Ecosystem
1° Producers, 1° Consumers, 2° Consumers, 3° Consumers
plus Detritivores / Decomposers
Food chain (Fig. 2.17) & Food web (Fig. 2.16)
Starts with primary production
Great energy loss through food chain (see pp 42-43):
= Energy Pyramid (see Fig CL2.1 & CL2.4) [Fig CL2.2 demonstrates some specific causes of energy losses]
10% Rule = 10% of energy transferred at each step (90% Energy lost with each step)
2) Nutrient Cycling
Reservoirs and Flows between them
Atmospheric —> Global cycle
Sedimentary —> Local cycles
Examples: Carbon cycle, Nitrogen cycle, Sulfur cycle, Phosphorus cycle (each have their own attributes)
Know details of the Carbon Cycle (see Fig. 2.19):
Assimilation (plants absorb CO2) —> Animals (Feeding) —> Death & Litter —> Decomposition —>
(Resp. losses from all)
Know details of the Nitrogen Cycle (see Fig. 2.20 & page 33 for role of N):
N-fixation —> Nitrification —> Assimilation —> Ammonification —> Denitrification
(except for assimilation, these steps all involve bacteria!)
Text Coverage: Chapter 2 (but not Elements of Life - pp 29-32)
Ecological Communities (10 questions)
The Environment and Organism Distribution (tolerance limits & critical factors)
Limits for survival, growth, and reproduction differs between species, but also within a species (see Fig. 3.4)
Plant distributions limited mostly by abiotic factors:
Temperature, water, nutrients, (light)
Animal distributions determined mostly by plants, secondarily by temperature, water
Community Properties
Species diversity (abundance)
Complexity & Connectedness
Resilience & Stability
(Text includes Productivity, but this is more of an Ecosystem property)
Species diversity is result of Evolution and Speciation (see A Closer Look, pp 56-57)
Speciation results from many processes:
Some of the most important are among the species interactions within Community (e.g., niche partitioning)
Species interactions (—> Co-evolution!):
Predation, competition, symbiosis
Prey Defense (shells, spines, Avoiding predation (camouflage, mimicry, aposematic coloration)
Interactions can be within trophic levels (competition) or between trophic levels (predation, most symbioses)
Interactions can be beneficial or harmful to either species (Table 3.2)
Species Niches (Result of interactions ––> adaptations & speciation)
Resource partitioning to avoid competitive exclusion (Fig 3.8 & CL3.4)
Niche breadth (Specialist vs generalist species) (see Fig. 3.4, p57)
Niche differentiation leads to Species Diversity (one of the reasons Topical Forests have such high diversity)
Generalist vs. Niche specialists
Invasive species are usually generalists
Dominant species
Keystone species (e.g., Sea otters)
Community Structure & Dynamics
Patches, Edges (Fig. 3.26), Ecotones, Corridors, Vertical Stratification, (Fig. 3.24)
Succession:
Secondary succession follows a disturbance which destroys most of the vegetation, but not the soil:
Opportunistic species —> Mid stages —> Climax community
Primary succession follows a disturbance resulting in loss of soil (or in a new landscape):
Pioneer species —> Mid stages —> Climax community (see Fig. 3.28)
Text Coverage: Chapter 3 [excluding Section 3.3]
Example questions:
1.
Which statement is INCORRECT regarding quality of life differences between the least developed and most developed
countries, respectively?
a. Life expectancy of less than 45 years versus greater than 75 years
b. Total fertility rate of about 5 versus less than 2 children
c. Adult literacy of 60% versus 100%
d. CO2 emissions of less than 500 lbs per person per year versus more than 10 tons per person per year
e. Annual GDP of about $3,000 dollars per person versus more the $30,000 per person
2.
Which of the following would be a Community-level ecological study?
a. an animal and its physical environment
b. competition among plants having different niches
c. decomposition rates by a group of microorganisms
d. primary productivity of phytoplankton in an estuary
e. an analysis of energy obtained by herbivores consuming plants
3.
The main reservoir (pool) of nitrogen (N) in the biogeochemical nitrogen cycle is
, and the primary
organisms (or process) responsible for obtaining N from this main pool and thus making it available to all other organisms are
(is)
.