The whole of ecology Flashcards
(135 cards)
1
Q
Define biodiversity
A
Measure of variation found in the living world
2
Q
What is a habitat
A
Where a specific species lives
3
Q
What is a species?
A
A group of organisms that can reproduce to produce fertile offspring
4
Q
List the types of sampling
A
Random
Stratified
Opportunistic
Systematic
5
Q
What are some ways of sampling insects?
A
Sweep nets
pooter
pitfall traps
Tullgren funnel (leaf litter dries, small animals fall through mesh)
light trap
6
Q
How would you sample small animals?
A
Longworth trap
7
Q
How do you estimate population size?
A
Capture recapture
(Amount of insects captured in the first sample x Amount of insects captured in the second sample that haven’t been marked)/ Amount of insects captured in the second sample that have been marked
8
Q
Limitations of capture recapture?
A
Insects may learn to avoid the trap
Insects may deliberately go to trap when they learn there’s food
9
Q
What is species richness?
A
How many diff species are present
10
Q
what is species evenness?
A
How evenly represented the species are
11
Q
How do you calculate species evenness in a population?
A
Simpsons index of diversity
12
Q
How do you calculate species richness in a population?
A
Counting the species
13
Q
Other than simpsons index, how else would you measure genetic diversity?
A
percentage of gene loci with multiple alleles
14
Q
What is it called when a gene loci has more than one allele?
A
Polymorphic gene loci
15
Q
What is monoculture?
A
A crop consisting of one strain of species
16
Q
What are the factors affecting biodiversity?
A
Human population growth
Agriculture (selective breeding and monoculture)
Climate change
Extinction
17
Q
What are the reasons to protect biodiversity?
A
- Ecological: protecting keystone species
(interdependence of organisms) and
maintaining genetic resource. - Economic: reducing soil depletion (continuous
monoculture). - Aesthetic: protecting landscapes.
18
Q
What is a keystone species?
A
One that has a disproportionate effect on its environment relevant to its abundance
19
Q
What is soil depletion?
A
Loss of soil fertility from the loss of nutrients caused by continuous farming
20
Q
What is conservation in-situ?
A
Carrying out active management to maintain the biodiversity in the natural environment
21
Q
What are marine conservation zones?
A
areas of the sea set aside to conserve the diversity of species and habitats
22
Q
What are wildlife reserves?
A
areas set aside to conserve the diversity of species and habitats
23
Q
What are the methods of in-situ preservation?
A
marine conservation zones
wildlife reserves
legislations
24
Q
What is important to consider when choosing a wildlife reserve?
A
- Comprehensiveness: how many species are represented
- Adequacy: is it large enough for the long term survival of lots of species?
- Representativeness: Is there a full range of diversity within each species?
25
What is ex situ conservation?
Conservation outside the normal habitat for the species
26
What are the methods of ex-situ preservation?
seed banks
botanic gardens
zoos
27
What is CITES
The Convention on International Trade of Endangered Species
28
What is the countryside stewardship scheme?
A scheme encouragin farmers and landowners to preserve their land in a way that promotes biodiversity
29
What is the Rio Convention on Biological
Diversity
promotes sustainable development
30
What is a binomial system?
A system that uses the genus name and the species name to avoid confusion
31
What is the classification hierarchy?
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
32
What are the three domains?
Archea, Eubacteria, Eukaryotae
33
What are the five main kingdoms?
Plantae, Anamalia, Fungi, Protoctsta (eukaryotes)
and Prokaryotae
34
How did scientists previously classify organisms?
Looking at how similar they were
35
Features of Prokaryotae?
- No nucleus, loop of DNA
- No membrane bound organelles
- Smaller ribosomes
- Smaller cells than eukaryotes
- Free-living or parasitic
36
Features of Protoctista?
- Eukaryotes
- Mostly single-celled
- Basically things that don't qualify elsewhere
37
Features of Fungi?
- Eukaryotic
- Have a mycelium that consists of hyphae
- Cell walls made of chitin
- Multinucleate cytoplasm
- free-living and saprophytic (cause decay of organic matter)
38
Define saprophytic
Something that causes decay of organic matter
39
Features of Plantae?
- Eukaryotic
- Multicellular
- Cells surrounded by cellulose cell wall
- Autotrophic
- Contain chloroplasts
40
Features of Animalia?
- Eukaryotic
- Multicellular
- Heterotrophic ( Digest large organic molecules into smaller molecules for absorption)
41
What are the biological ways to measure evolution?
Cytochrome C amino acid sequencing
DNA sequencing
42
What did Carl Woese do?
Divided prokaryotae into two separate groups:
Bacteria (Eubacteria)
and Archaea
43
What is the difference between Bacteria and Archaea?
Different cell membrane structures
Bacteria don't have any protein bound to their genetic material
Different methods of DNA replication
44
Describe artificial classification
Based on only a few characteristics
Does not reflect any evolutionary characteristics
Provides limited explanations
45
Describe natural classification
Based on lots of characteristics
Reflects evolutionary characteristics
Provides detailed explanation
Changes with advancing knowledge
46
What is phylogeny?
The study of the relationship between species
47
What did Darwin and Wallace contribute to the theory of evolution?
- Offspring seem similar to their parents
- No two individuals are identical
- Organisms have the ability to produce large numbers of offspring
- Populations in nature tend to be stable in size
48
What is the evidence for evolution?
Fossil evidence
Biological molecules (cytochrome c)
49
What is continuous variation?
When there are two extremes and a range of variables in between
50
What is discontinuous variation?
Distinct categories and nothing in between
51
What is environmental variation?
Variation caused by environmental factors such as light intensity
52
What is genetic variation?
Variation caused by inheriting a different arrangement of alleles
53
What is interspecific variation?
Differences between species
54
What is intraspecific variation?
Differences between the members of the same species
55
What is adaptation?
A characteristic that enhances survival in the habitat
56
What is an anatomical adaptation?
Structural features
57
What is a behavioural adaptation?
Behaviour modified for survival
58
What is a physiological adaptation?
Change to processes
59
Why may species from different taxonomic groups show similar anatomical features?
If they live in a similar environment they may both evolve similarly to adapt (convergent evolution)
60
Steps of natural selection?
1. Mutation causes variation in allele
2. Creates intraspecific variation
3. Varied characteristic is advantageous
4. Survive and reproduce
5. Pass on genetic advantage
6. Next generation higher proportion of members with advantage
61
What are some of the implications of natural selection in organisms for humans?
- Insects become pesticide resistant
- Microorganisms evolve to become resistant to antibiotics
62
What is a biotic factor?
Environmental factors associated with living organisms in an ecosystem that affect each other
63
What is an abiotic factor?
non-living components of an ecosystem that affect other living organisms
64
What is an ecosystem?
community of animals, plants, and bacteria interrelated with the physical and chemical environment
65
What are the components of an ecosystem?
- Habitat (place where organism lives)
- Population (all the organisms of a species who live in the same place at the same time who can breed together)
- Community (all the populations of the different species who live in the same place at the same time, and who can interact with each other)
66
What is a community?
all the populations of the different species who live in the same place at the same time, and who can interact with each other)
67
What is a niche?
The role of each organism in an ecosystem
68
Name some biotic factors
- Producers: Plants which supply chemical energy to all other organisms
- Consumers: Primary (herbivores), Secondary (eat herbivores), Tertiary (eat secondary)
- Decomposers: feed on waste materials or dead organisms
69
Name some abiotic factors
- pH
- Humidity
- Temperature
70
Why are ecosystems referred to as dynamic?
Because they change
71
Name the types of change in an ecosystem
- Cyclical change: changes that repeat themselves in a rhythm (eg. tides)
- Directional changes: go in one direction and tend not to change back in a while
- Unpredictable/ erratic changes: No rhythm or constant direction (effects of lightning or hurricane)
72
What is a biomass transfer?
A transfer of biomass from one trophic level to the next
73
What is a trophic level?
Level at which an organism feeds in the food chain
74
How is biomass lost in transfer?
- Respiration converts organic molecules to heat]
- Lost from food chain in dead organisms, energy transferred over to decomposers
75
What does a pyramid of biomass represent?
The area at each level represents the dry mass and approximate biomass in a trophic level
76
How do we measure the transfer of biomass?
Using a pyramid of biomass
77
How do we calculate the efficiency of biomass transfer?
Heat species up to 80 degrees until water evaporated.
Efficiency= biomass at higher level/ biomass at lower level
78
How can we increase primary productivity?
- Manipulate light levels
- Irrigation or drought-resistant crops
- Grow plant in greenhouses to increase temperature
- Crop rotation (stops the reduction of certain inorganic ions in soil)
- Pesticides
79
Define productivity
The rate of production of new biomass by producers
80
What is gross primary productivity?
Rate at which plants convert light energy into chemical energy through photosynthesis
81
What is net primary productivity?
The actual amount of energy that remains in the food chain produced by a primary producer
82
How can we increase primary productivity?
- Killing animals while younger (less energy invested into growth)
- Selective breed animals with faster growth rate
- Treat animals with antibiotics to avoid energy loss when fighting bacteria
- Zero grazing reduces energy wasted walking around
83
What are the steps of saprotrophic decomposition?
1. Saprotrophs secrete enzymes onto dead and waste material
2. Enzymes digest the materials into small molecules to be absorbed into the body of the saprotroph
3. Molecules are stored or respired to be used for energy
84
List the steps of the Nitrogen cycle
1. Nitrogen fixation
2. Ammonification
3. Nitrification
4. Denitrification
85
Describe the process of nitrogen fixation
Nitrogen gas -> Nitrogen containing compounds
Azotobacter and Rhizobium bacteria contain nitrogenase enzyme to convert nitrogen and hydrogen into nitrogen containing compounds
86
What is the bacteria involved in Nitrogen fixation?
Azotobacter
87
Is Nitrogenation reduction or oxidation
Reduction
88
Describe the process of Ammonification
Production of ammonia from organic compounds e.g. urea, proteins, nucleic acids.
Saprobiotic microorganisms (bacteria & fungi) feed on these to release ammonia into the soil
89
Describe the process of Nitrification
Ammonium ions are converted into Nitrite ions (NO2-) by Nitrosomonas
Nitrite ions are oxidised into nitrate ions (NO3-) by Nitrobacters
90
What (other than the bacteria) is required for nitrification?
Oxygen
91
Describe the process of denitrification
Denitrification removes nitrates from the soil by denitrifying anaerobic bacteria, converting it into nitrogen gas
This stops plants accessing nitrates
92
How do we stop denitrification?
If it happens in anaerobic conditions...
We must
- Keep soil aerated
- Keep the soil well-drained so that water does not clog air pockets
93
What are the three main steps of the carbon cycle?
1. Respiration
2. Photosynthesis
3. Decomposition
94
Describe how respiration works in the carbon cycle
Plants and consumers will respire and release CO2 into the atmosphere
When they die, decomposers will also respire and release CO2 into the atmosphere
95
How does respiration work in the carbon cycle?
Plants absorb sunlight and photosynthesise, to do so, they also require CO2 from the atmosphere
96
How does decomposition work in the Carbon cycle?
Decomposers will break down dead organisms into smaller carbon-containing compounds (sedimentation)
These compounds become fossil fuels, that can be combusted to release energy, releasing CO2 into the environment
97
Outline the generic process of primary succession
1. The arrival of a resilient pioneer species in an abiotic environment
2. Decreases the hostility of the environment
3. Leading to colonisation of more complex species who further decrease the hostility of the environment
4. Gradually outcompeting and replacing the pioneer species
5. Until a stable 'climax community' is established
98
What is a climax community?
Final stable community achieved from resulting succession
99
What things increase when succession occurs from a pioneer species to a climax community?
- Abiotic/ environmental favourability
- Variety of habitats and niches
- Biodiversity
- Interdependence
- Productivity
100
What are the two types of succession?
Primary and secondary
101
What is primary succession?
Succession starting from perviously uninhabited environment
102
What is secondary succession?
Succession restarting from an interrupted ecosystem
103
What is deflected succession?
Succession to an alternative community as a result of human interference, biotic factors, or abiotic factors
104
What are the three things that lead to deflected succession?
- Human interference
- Biotic factors
- Abiotic factors
105
Examples of biotic factors leading to deflected succession?
Trampling, grazing
106
Examples of abiotic factors leading to deflected succession?
Wave action, fires
107
Define carrying capacity
The maximum stable population for a species in a habitat. It is reached in the stationary phase of the growth curve
108
What abiotic factors define carrying capacity?
Temperature
Light intensity
pH
Water availability
Oxygen concentration
CO2 concentration
109
In a growth curve, why may the growth phase slow down and enter the stationary phase?
- Waste product buildup
- Some nutrients limiting
- Abiotic factors may no longer be suitable
110
What is a k-strategist?
Population size determined by carrying capacity
111
What are r-strategists?
Population not determined by carrying capacity but their rate of reproduction
112
What are some of the characteristics of k-strategists?
- Slow reproduction
- Slow development
- Late maturity
- Extended parental care
- Larger
- Longer life
113
What are some of the characteristics of r-strategists?
- Fast reproduction
- Fast development
- Early maturity
- Little/no parental care
- Smaller
- Shorter life
114
What are the biotic factors that affect climax community?
- Interspecific selection
- Intraspecific selection
- Predator- prey interaction
- Pathogenic diseases
115
Define conservation
Active and dynamic interventions by humans to maintain or improve biodiversity
116
Define preservation
Maintenance of habitats and ecosystems in their present condition, minimising human impact
117
What are the three reasons we conserve biological resources?
- Economic
- Social
- Ethical
118
What are the ethical considerations made when conserving biological resources?
All living things have value and should be protected
119
What are the economic considerations made when conserving biological resources?
- Food crops need wide varieties to survive
- Plants and microbes might be sources of future medicines
- Pollinating animals increase crop reproduction
120
What are the social considerations made when conserving biological resources?
Tourism
121
What are some ways an timber can be conserved in a sustainable way?
- Pollarding
- Coppicing
122
What is pollarding?
Chop branches off: conserves wood stock and prevents grazing
123
What is coppicing?
When a tree is cut close to ground level, several new shoots grow from ground surface, process repeat
Rapid new stem growth
Varied light levels
Variety of habitats
Prevents soil erosion
124
What is the FSC?
The forest stewardship council
125
What are the aims of the FSC?
- Ending clear felling
- Re-forestation
- Ecological functionality
- Benefit local community
- Selective felling
- Sustainable forestry
126
What is the MSC?
Marine stewardship commitee
127
What are the aims of the MSC?
- Sustainability (maintain carrying capacity of fish)
- Ecosystem impacts (not damaging ecosystem)
- Good management (obeying legal restrictions)
128
What are some of the legal restrictions surrounding fishing?
Annual quotas
Mesh sizes
Restrict certain species
Boat sizes
Sailing duration
Monitoring / inspections
129
What are some of the criticisms of the MSC's laws?
- Fishing zones too large to monitor so not enforced
- Monitoring expensive
- False reporting of catch size
- Fish die when thrown back if over quota
130
Issues with fish farming?
Higher risk of parasites, ugly, pollutes waterways
131
What were some examples of human-animal conflicts
- Humans attacked by wildlife
- Cattle killed by wildlife
- Crop raids by wildlife
- Chemical fertiliser use
- Forest wood used as fuel
- Poverty driving behaviours like poaching
132
How were the issues in the human- animal conflicts resolved?
- People allowed to exploit forest, whilst also looking after it
- Solar-powered electric fences
- Wildlife corridors
- Anti-poaching patrols
- Tourist management
- Conservancies set up so humans can manage land. Benefits both domesticated and wild animals
133
What is a wildlife conservancy?
Collaborations between many land owners around the Maasai Mara and tourism companies.
Land owners receive incomes to promote conservation, de-fence, and sustainable land use.
134
What are some of the ways human activities effect the animal and plant population?
- Over-exploitation of resources
- Introduced species
- Drainage ditches -> poor water quality elsewhere
135
How are the effects of human activities on plant and animal populations controlled?
- Paid initiatives
- Reduce tourism
- Legal protections
