Ecology

Question 1

species

Answer 1

group of organisms that can interbreed + produce fertile offspring

Question 2

population

Answer 2

group of organisms of same species who live in same are at same time

Question 3

community

Answer 3

group of populations living and interacting in same area

Question 4

ecosystem

Answer 4

community and abiotic environment

Question 5

abiotic

Answer 5

elements like weather, water, geology

Question 6

environment

Answer 6

surrounding conditions where organism lives

Question 7

producer

Answer 7

organism that makes own food (mostly using sunlight)

Question 8

consumer

Answer 8

organism that ingests organic matter that’s alive or recently killed (not already decomposed)

Question 9

decomposer

Answer 9

organism that breaks down dead organic matter into smaller pieces

Question 10

saprotroph (and example)

Answer 10

organism that lives on or in non-living matter, secreting digestive enzymes into it and absorbing the product (digest outside of body)
Ex: mushrooms

Question 11

detritivore (and example)

Answer 11

organisms that ingest non-living matter (already decomposed)
Ex: earthworms

Question 12

autotroph

Answer 12

organisms that synthesize their organic molecules from simpler inorganic substances (like plants): aka producers (self-feeding)

Question 13

hetertroph

Answer 13

organisms that obtain organic molecules from other organisms (not photosynthesis): feed on others

Question 14

what 3 thins are necessary for sustainability

Answer 14

nutrient availability, detoxification of waste products, energy availability (sun)

Question 15

what is a mesocosm

Answer 15

a small experimental area set up as ecological experiments (often sealed with variables manipulated)

Question 16

what is a trophic level

Answer 16

an organisms position on the food chain (producers, primary, secondary, tertiary…)

Question 17

what is an energy pyramid

Answer 17

diagram showing the amount of energy flow through each trophic level

Question 18

what is carbon fixation

Answer 18

autotrophs (plants) convert CO2 into organic carbon compounds through photosynthesis (aka plants absorb carbon into their biomass)

Question 19

what is methanogenesis

Answer 19

methane produces in anaerobic conditions (swaps etc) by methanogenic archaeans, then methane can be oxidized into CO2 + water vapor in atmosphere.

Question 20

what is peat

Answer 20

forms when anaerobic and acidic conditions prevent organic matter from fully decomposing ( can form coal and contain fossils), often in waterlogged soils

Question 21

what is combustion

Answer 21

a reaction between carbon compounds and O2 to produce CO2 + water, like forest fires and burning of fossil fuels

Question 22

what is a carbon flux

Answer 22

the transfer of carbon from one pool to another (CO2 goes from cell respiration to atmosphere to photosynthesis)

Question 23

what is a carbon pool

Answer 23

where carbon gets detained in the cycle (in atmosphere, organic compounds, dead organic matter etc)

Question 24

what is a greenhouse gas

Answer 24

CO2, water vapor, methane, nitrous oxide
- ability to absorb long wave radiation + abundance determine impact

Question 25

what is the precautionary principle

Answer 25

companies planning to do something first must prove it will not cause harm: puts burden on company polluting

Question 26

how do greenhouse gasses cause warming of the earth?

Answer 26

• short-wave radiation (~400 nm) comes from sun and strikes earth (20-30% of short length first absorbed by ozone)
• earth absorbs light and re-emits at much longer peak wavelength of ~10,000 nm
• as the longer wavelength radiation goes back, about 75-80% is absorbed by GG’s like water vapor, CO2, and methane
• methane can absorb more radiation/molecule than CO2, but CO2 is much more abundant
• GG’s re-emit radiation is all directions, some go back to earth causing it to warm
• the “greenhouse effect” keeps the earth warm enough for human habitation (it would be -18 degrees without)

Question 27

what evidence supports human-caused climate change?

Answer 27

• greenhouse gases have been on the rise since industrialization in 1850
• temps have been rising too, but have really taken off since 1950 (hockey stick graph)
• global temps have rise 1.1 degrees C since industrialization
• 7 hottest years on record have occurred since 2015, expected to rise more this century

Question 28

what is biomagnification

Answer 28

as you go up in the energy pyramid, levels of some toxins increase to dangerous levels (mercury in tuna)

Question 29

what is limestone

Answer 29

calcium carbonate of coral and mollusks that is fossilized

Question 30

outline reasons why energy is lost in on energy pyramid

Answer 30

• organisms die before before consumption
• some parts not eaten or passed in feces
• cellular respiration energy transferred out as heat

Question 31

outline the calculations necessary for a chi-squared test

Answer 31

• expected frequency = row totals x columns total / grand total
• degrees of freedom = (m-1)(n-1) [m is columns, n is rows]
• if chi-squared is LESS than critical, there is NOT association (less than 5%)
• if chi-squared is MORE than critical, there IS association (more than 95%) from sun nutrients, symbiotic