IB Biology SL 2007
1) The number of niches increases from pioneer species to climax species during succession.
2) Biodiversity increases from pioneer species to climax species during succession.
3) Pioneer Plants / Pioneer Species
4) Climax Community / Climax Species
5) Interspecies Competition occurs as one species replace another during succession.
6) Pioneer Plant Examples (Any type of weed mentioned: Dandylions, Clover, blackberries, scotsbroom) and others: moss, lupine, fireweed, etc…..
7) Pioneer plants of bare rock: Lichens and mosses
8) Mutualism
9) Niche
10) Eutrophication = buildup of nitrates, phosphate and other nutrients in rivers or lakes. These “fertilizers” cause a rapid growth of algae which consume all the oxygen in the water, killing everything.
11) CFCs (Chloroflurocarbons)
12) (2 damaging effects of UV light on life) 1) Damages cell DNA, causing mutations. 2) Causes cancers (especially of skin.) 3) Causes severe sunburn and eye cataracts. 4) Reduces photosynthesis rates in plants & algae, affecting food chains.
13) In situ conservation = conserving the species in its own habitat.
14) Ex situ conservation = conserving a species by removing the species from its habitat and preserving it in a zoo, game farm, garden, etc.
15) A) Lichen on a rock (an example of primary succession.
16) B) reforestation after a forest fire.
17) 2 examples of soil preparation here: 1) Organic matter added to soil by plants and animals. 2) Decay adds organic matter to deepen soil. 3) Water retention increases as organics are added. 4) Roots prevent erosion. 5) Amount of mineral recycling increases as the soil holds more nutrients.
18) Climax forests have more biodiversity (& niches) than a field.
19) 2 examples of Ex situ Conservation: a) captive breeding b) zoos c) seed banks d) botanical gardens
20) 2 examples of In situ Conservation: a) National Parks b) nature reserves c) urban greenspaces d) Wildlife Refuges
21) 2 advantages of insitu conservation: 1) Species remain adapted to their habitats 2) Greater genetic diversity is conserved. 3) Animals maintain natural behaviors 4) Species can still intereact, helping to conserve the whole ecosystem.
22) Recently extinct species: a) Passenger pigeon (hunted for feathers), b) dodo (easy to kill, hunted for food),
23) 1Ethical reason to conserve biodiversity: 1) Every species has a right to live. 2) Wrong to deprive future humans of the biodiversity seen today. 3) Wildlife have cultural importance to local human populations, so it is wrong to destroy it.
24) 1 ecological reason to conserve biodiversity: 1) Species are interdependent (part of food webs), so if 1 goes extinct, the others are impacted. 2) Native species are adapted to local conditions, whereas alien species that replace them are not as well adapted. 3) Damage to ecosystems can have wide effects, including erosion, flooding, changes to weather.
25) 1 economic argument to conserve biodiversity: 1) New crops, farm animals or pets may be developed from newly found species. 2) Many organisms might be a source of medicines. 3) Ecotourism may provide income for impoverished rural areas.
26) 1 esthetic argument to conserve biodiversity: 1) Natural ecosystems & species are beautiful or give us great enjoyment. 2) Painters, writers & composers have been inspired by nature.
27) Organisms are difficult to classify into 1 specific trophic level if they feed at different levels in different food chains (ex: omnivores).
28) There is so little biomass and low numbers of organisms at higher trophic levels of food chains because so little energy makes its way there (only 1% for a secondary consumer).
29) 2 factors affecting distribution of animal species: a) temperature, b) water, c) breeding sites, d) food supply, e) territory.
30) 2 factors affecting distribution of plant species: a) temperature, b) water, c) amount of sunlight. d) pH of soil, e) mineral nutrients. F) salinity of soil.
31) Intraspecific Competition (snow leopards are the same species)
32) Interspecific Competition (lions and hyaenas are 2 different species)
33) Competitive Exclusion Principle: Only 1 species can occupy a niche at a given time.
34) Carrying Capacity = The maximum number of members of a species the resources and predators in the ecosystem will support at a given time.
35) Random Sample = A method to sample populations randomly so each individual has an equal chance of being sampled. (Reduces error for the study)
36) Trophic Level = The level in a given food chain in which a specific species “feeds” or obtains its energy.
37) 2 methods to reduce CFCs level in atmosphere: 1) use CFC-free aerosols. 2) Use refrigerators, freezers & air conditioners with safe coolant. 3) Use food- or product- packaging free of CFCs.
38) 1 reason to conserve world’s fish: 1) Major food supply for humans. 2) Parts of major food chains, their loss means disruptions of these food chains.
39) 2 measures to protect fish species from overexploitation: 1) Monitor numbers of fish & their reproductive rates. 2) Set quotas (how many fish can be caught) for species with low numbers. 3) Prevent catch of endangered species. 4) Set minimum size of nets, so young are caught. 5) Ban drift nets which catch many unwanted species.
40) Nutrients can endlessly be recycled through food chains. Energy can move through a chain only once.
41) 2 consequences of acid precipiation: 1) Conifer trees are very sensitive to low pH (weakens trees). 2) Fish and aquatic insects are sensitive to changes in pH, killing them & disrupting food chains. 3) Acids leach key minerals from soil, making soil less fertile. 4) Acids leach aluminum out of soil. Aluminum in water becomes toxic to fish.
42) 2 methods to prevent acid precipitation: 1) Neutralize all chemical wastes before disposal. 2) Use catalytic converters on engines to prevent release of chemicals to air that can be converted to acids. 3) Convert from engines run on fossil fuels to solar, hydrogen, fuel cells, or wind as energy source.
43) One source of acid precipitation: 1) Burning produces CO2 which can be converted to carbonic acid. 2) Internal combustion engines (produces either sulfur dioxide which is converted to sulfuric acid or produces nitrogen oxides that are converted to nitric acid.)
44) Nitrogen fixation: Bacteria in soil convert free nitrogen (N2) in air into ammonia (NH3).
45) Ammonification: Saprotrophs convert amino acids back to ammonia (NH3) in soil.
46) B) Nitrification converts ammonia first to nitrites (NO2), then into nitrates (NO3).
47) Denitrification converts nitrates in soil to free nitrogen (N2) in air when there is no oxygen in the soil.
48) Nitrogen fixation converts nitrogen (N2) in air into ammonia (NH3).
49) Two methods to add nitrate to soil: a) Add nitrogen fertilizer (not natural). b) Compost (add plant wastes and animal wastes to soil. c) Plow / aerate soil to add oxygen (aids nitrification). d) Crop Rotation: Plant nitrogen fixing plants (legumes) on alternate years. e) Drain fields to improve aeration.
50) Nitrosomonas converts ammonia (NH3) to nitrite (NO2).
51) Nitrobacter converts nitrite (NO2) to nitrate (NO3).
52) Azotobacter converts nitrogen (N2) to ammonia (NH3). Rhizobacter does the same thing but is found in plant roots, not free in the soil.
53) Pseudamonas denitrificans converts nitrate (NO3) into nitrogen (N2) in the air when the soil is water-logged and contains low oxygen.
54) Nitrification converts ammonia first to nitrite(NO2), then into nitrate (NO3).
55) Ammonification (by saprotrophs) converts dead organisms back to ammonia in the soil.
56) Nitrogen fixation converts atmospheric nitrogen (N2) to ammonia (NH3) in the soil.
57) Denitrification converts nitrate (NO3) in oxygen poor soils back into atmospheric nitrogen (N2).
58) Many of the producers must be dieing as there is a large amount of energy in the saprotrophs & detritivores.
59) A pyramid of numbers may have a low number of producers when those producers are very large (like trees) and the herbivores are small (like insects).
60) In a pyramid of energy, the producers must always have the most energy, as about 90% of the energy is lost between the producers and the next level above it.
61) Herbivore = plant eater
62) Carnivore = meat eater
63) Omnivores eat roughly equal amounts of meat and plants
64) Detritivore
65) B) Autotroph
66) A) Chemotroph
67) C) Heterotroph
68) D) Saprotrophs
69) Sunlight (the sun)
70) Producer = green plants
71) Primary consumers = herbivores (plant eaters)
72) Secondary consumers = carnivores (meat eaters) - Omnivores are best used in food webs.
73. Food web = manyinterconnected food chains
74. Abiotic (nonliving) factors of environment = water, soil, air, rocks, pH, salinity, etc.
75. Biotic factors of the environment include all living things, plants, animals and fungi (etc.) that are part of the ecosystem.
76. Biosphere = the thin layer of all ecosystems that covers the surface of the earth.
77. Greenhouse gases = the main two are carbon dioxide (CO2) and methane (CH4). Others include sulfur dioxide (SO2), and water vapor.
78. Short wavelengths of light from sun pass thru the atmosphere and strike the earth, warming the earth’s surface. The earth emits heat of longer wavelength. Greenhouse gases act like a lid and trap the longer wavelength energy, heating the air.
79. Two consequences of increased greenhouse effect: a) global warming, b) melting glaciers and polar ice caps, c) rising sea level (expansion of water & melting of glaciers), d) flooding of coastal areas and coral atolls, e) more frequent (more energetic) storms, f) changes in weather patterns, g) diseases (like malaria) move further towards poles
80. One measure to reduce greenhouse effect: a) Restore forests, b) Change from fossil fuels to non-carbon based energy sources, c) Reduce energy consumption (fuel efficient vehicles, better home insulation, eat locally grown food, etc.), d) spread nutrients (iron) to oceans to promote growth of algae.
81. Parasitism
82. Mutualism
83. Two animal parasites: a) tapeworms, b) flukes, c) leeches, d) ticks, e) fleas, f) lice, g) ringworms, h) athletes foot, etc…..
84. Plant parasite: a) mistletoe, b) dodder, c) paintbrush
85. Example of a mutualistic relationship: a) clownfish & sea anemone, b) boxer crab & sea anemone, c) coral and calcium-fixing algae, d) termite & wood-digesting beasties in its gut, e) rhino and tick birds, f) other reasonable answer.
86. Homo = genus name.
87. For a population to increase, C) Natality + immigration > mortality + emigration
88. sapiens = species name.
89. Canis lupus = B) binomial nomenclature
90. Mice Population = 60 (10 X 30 / 5)
91. One benefit of classifying organisms: a) aids species identification, b) helps predict whether similar organisms will have similar traits. C) Predicts evolutionary trends.
92. Five kingdoms of life: 1) Prokaryotae, 2) Protoctista, 3) Fungi, 4) Animalia, 5) Plantae
93. Hierarchy of classification: b) kingdom, phylum, class, order, family, genus, species.
94. D) Prokaryotae (prokaryotic cells have no nucleus, no organelles and naked DNA.
95. C) Protoctista
96. B) Fungi