Ecosystems Flashcards
1
Q
Population
A
A group of one species living in a particular area. The number of organisms of a species in a habitat
2
Q
Community
A
All the different organisms that live and interact in an ecosystem
3
Q
Organism
A
An individual animal, plant or single celled life form
4
Q
Ecosystem
A
All organisms and the environment in which they live in along with the biotic and abiotic factors that affect them
5
Q
Trophic level
A
The number of steps an organism is from the start of the chain
6
Q
Interdependence
A
How individual species depend on each other for resources
7
Q
Food chain order
A
Producer (plant), primary consumer, secondary consumer, tertiary consumer
8
Q
What do the arrows on a food chain show
A
Energy transfer - NOT who eats who
9
Q
Abiotic
A
Non-living factors in an ecosystem which can affect the distribution of organisms e.g. water, temperature, weather, pollutants, light
10
Q
Biotic
A
Living organisms in an ecosystem which can affect the distribution of other organisms e.g. humans, habitat, predators, competition
11
Q
Temperature affecting polar bears
A
(Abiotic) Increased temperature means that the polar ice caps would melt, decreasing the space on land where they can live
12
Q
Water affecting plants
A
(Abiotic) Lack of water means that plants cannot photosynthesise meaning they can’t get glucose for respiration so the number of plants would decrease
13
Q
What do organisms compete for
A
(Biotic) Shelter, space, food, water, mates, light, territory
14
Q
Predator-prey relationship
A
As the number of prey increases, the number of predators also increases. This is because the large number of prey will be able to feed and support a large number of predators (not much competition)
15
Q
Importance of interdependence
A
In order to maintain a balanced food web, organisms must rely on each other. This is because, in a food web, changes in the population of one species can have an effect on the populations of other species in the same community
16
Q
Competition
A
Habitats have limited supplies of the resources needed by plants and animals. They compete, including by fighting, in order to survive (survival of the fittest)
17
Q
Food chain
A
A sequence of feeding relationships between organisms showing energy movement through trophic levels
18
Q
Producers
A
Organisms that make their own organic nutrients - usually using energy from sunlight. (Autotrophic)
19
Q
Consumers
A
Heterotrophic. Get energy from other organisms
20
Q
Decomposer
A
Feed off dead and decaying organisms (saprophytic)
21
Q
Food web
A
A network of interconnected food chains. Shows energy flow through an ecosystem
22
Q
Pyramid of numbers
A
Shows population at each stage (trophic level) of a food chain. Bars are stacked on top of each other with producers at the bottom (most energy)
23
Q
Environment
A
All the conditions that surround a living organism
24
Q
Biodiversity
A
A measure of the variety of different species living in a habitat
25
Why is it impractical to count the organisms in a population
Animals may move in or out of the area during counting, some may die, may be difficult to find all organisms
26
Quadrat
A square made of wire used to identify and count the number of organisms in a small area
27
How to use a quadrat
Count population in small area then times by how many squares fit into the whole area. Remember that the quadrat must be randomly placed (representative sample) e.g. random coordinates not biased. The validity (repeatable) and reproducibility (ability to be reproduced to increase validity) of the results increases as the results are analysed. Smaller boxes to know exactly where to take measurements e,g, temperature. Known size (usually 10x10) easy for percentages.
28
Capture mark recapture
A way to estimate the population size of an animal species. Trapped (pitfall). Marked then released. Traps used a few days later. Marked and unmarked counted and recorded.
29
Equation for capture mark recapture
2nd sample previously marked / 1st sample x 2nd sample
30
Assumptions made with capture mark recapture data
No death, immigration or emigration, no tags have taken off or marks rubbed off, marking has not affected survival rate of the animals
31
Belt Transects
A line across a (part of a) habitat e.g. A string or rope on the ground. The number of organisms of each species is recorded at regular intervals or estimating percentage cover (percentage area of a quadrat with a certain type of organism). Also study distribution of abiotic factors such as mean height of plants or light intensity along a gradient (change cross a habitat). Find mean for each quadrat. Plot graph to see if the changing abiotic factor is in correlation with a change in the distribution of the species. Good for finding out changes along a gradient
32
Zonation
A gradual change in the distribution of species across a habitat
33
Parasites
Organisms that live on or inside of or near o a host organism. The parasite benefits but the host does not and/or may be harmed
34
Mutualism
The relationship between organisms of different species where they both benefit (symbiosis)
35
Head lice
Parasites. Live in human hair. Feed by sucking blood from the scalp. Effect the the host by bites causing itching
36
Fleas
Parasites. Live on the fur and bedding of humans and animals. Feed on sucking blood. Bites cause a risk of infection and itching
37
Tapeworm
Parasite. Live inside another animal attaching itself to its gut. Feed by absorbing water and nutrients in the gut. Host suffers from malnutrition
38
Mistletoe
Parasite. Live on trees (especially oak and apple). Feed on the nutrients by the roots invading the bark. Caused deformities in the trees and branches or death
39
Cleaner fish
Mutualist. Live with or alongside other fish and avoid being eaten by other fish. Feed on dead skin and ectoparasites. Host gets pest control
40
Oxpecker
Mutualist. Live on the skin of buffalo, deer and other animals. Feed on ticks and larvae. Host gets pest control and warning of nearby predators
41
Nitrogen fixing bacteria
Mutualist. Live in the nodules of roots of legumes such as beans, clover and peas in the soil. Feed on constant supply of sugar. Host gets nitrates from the bacteria which are used for proteins
42
Chemosynthetic bacteria
Mutualist. Live inside giant tube worms or gills of molluscs in hydrothermal vents. Feed on chemicals from the seawater provider. Host uses the chemicals to synthesise food for them and the host
43
Prey-predator graph cycle
Prey population increases when predator numbers are low. More prey means more food for predators. Population of predators increase after a lag time. Prey eaten by predators means that the prey numbers decrease. Less food for predators meaning fewer survive and predator numbers decrease. Cycle repeats. More prey population in general
44
Light intensity affecting plants and algae
More light means more photosynthesis which means more growth and therefore an increased distribution
45
Water pollution affect on fish
Pollutants poison fish, killing them and decreasing their distribution
46
Adaptations of parasites (headline)
Sharp claws to grip to hair and skin. Sharp mouth parts to pierce skin. Eggs glued to hairs to prevent them falling off
47
Adaptations of parasites (tapeworm)
Hooks and suckers to attach he head firmly to the international wall. Flattened body allows nutrients to be absorbed over the whole body surface. Segments contain make and female sex organs for fertilisation
48
Fish farming - pos and neg
(15% of protein earn by humans is fish) Aims to produce more fish to reduce overfishing of wild fish. Kept in freshwater or seawater tanks and enclosures. Pos: provides for humans, controlled number of predators to fish (protection), more sustainable, fish fed frequently and better (rapid growth), disease can be treated, makes sure no harmful substances are in the fish (safe to eat), controls fish reproduction and fish fights. Neg: disrupts food chains, disease can be more easily spread as fish are closely together in a confined space, pesticides and antibiotics may be needed, eutrophication may be needed, uneaten food and faeces sink to bottom which can pollute the water, may cause adaptations that change the fish, predators are attracted to the nets and can get caught and die
49
Intraspecific competition
Competition between individuals of the same species
50
Interspecific competition
Competition between individuals of different species
51
Indigenous
An organism that has been in an area for a very long time (native)
52
Non-indigenous
An organism that has been introduced into an area they haven't been in before
53
Benefit and neg of non-indigenous species
Reduces number of another species which is out of control (invasive species) - pest control/predators. Provide more food for a species where food sources are scarce - prey. Neg: changes biodiversity of an ecosystem, disrupts food webs, may form adaptations in evolving in that area, may carry a disease that can infect and kill indigenous species, reducing biodiversity
54
Naturalised species
When a non-indigenous species becomes established in the new environment
55
Invasive species
When naturalised species spread quickly and outcompete native species
56
Eutrophication and neg
Excessive richness of nutrients in a body of water, caused by fertilisers washed into it, which causes a dense growth of plant life (phosphate and nitrates increases algae growth). This destroys the ecosystem as oxygen levels reach a point where no life is possible and all organisms die.
57
Process of eutrophication
Happens in a river or lake. It is full of excessive nutrients such as nitrates and phosphates from fertilisers which stimulates algae growth. The algae covers the water surface, absorbing sunlight preventing it from reaching other plants under the water which then die. The oxygen in the water is also depleted. Bacteria reproduce by consuming oxygen and feeding off dead plants, breaking them down and leaving the river anoxic (without oxygen)
58
Preserving biodiversity importance
Conservation and reforestation. Protects human food supply, ensures minimal damage to food chains, provide future medicines, cultural aspects, ecotourism, provide new jobs
59
Conservation and pos
When an effort is made to protect and preserve a rare or endangered species or habitat such as the rainforest or red squirrels. This helps the species population to survive and thrive, boosting the ecosystem and food webs
60
What does the habitat provide a source of?
Food, water, shelter, protection from predators, mates, minerals
61
Reforestation and pos
Replanting trees to protect a habitat. This serves as shelter, homes, safety and food for many organisms (from predators, weather, source of prey). Increases biodiversity.
62
Case Study. What was Kielder Forest like before?
(100years ago) Trees were gone and it was mostly open moorland. Animals such as deer and grouse lived there. It was once covered by trees.
63
Case Study. What was Kielder Forest originally planted with?
Conifer trees (pines) to provide wood
64
Case Study. How has Kielder Forest changed?
Both conifers and broad leaves trees are planted and some areas are left open to increases the range of habitats and number of species living there
65
Case Study. What rare species are occupying Kielder Forest?
Osprey, goshawk, red squirrel
66
Case Study. What has been done to protect endangered species in Kielder Forest?
Nesting platforms built in tall trees to encourage ospreys to nest
67
Case Study. How is squirrel conservation managed?
Grey squirrels caught and killed to protect the red squirrels
68
Importance of preserving biodiversity
Conserves individual species and communities. Also useful as it means that areas with greater biodiversity can recover faster from natural disasters such as flooding. Plants and animals are also used by humans for food and a source of medicine.
69
Food security
The ability of human populations to access food of sufficient quality and quantity (access, quality and quantity)
70
Increasing human population on food security
The rapid rise in human population has resulted in increasing demand for food worldwide. This is an issue for individuals, households and entire countries. More people want to consume more food
71
Temperature affecting birds
Rise in average temperatures cause the distribution of birds to change especially in Germany (e.g. European Bee Eater birds)
72
Water affecting daisies
Grow best in slightly damp soil. Waterlogged or too dry means they decrease
73
Light intensity on fungi
Thrive in dark conditions. Trees replaced by misses
74
Pollutants in air on lichen
Unable to survive if concentration of sulfureux dioxide is too high
75
Decreasing red squirrels
Grey are competing and winning by eating their food
76
Quadrat mean equation
Total number of organisms / number of quadrats
77
Estimate population size from quadrants
Mean number of organisms per m^2 x total area of habitat
78
Sustainable food production
Make sure enough food for future demands. Produce more food in same area of land, therefore increased plant productivity and manipulation of genetic diversity required.
79
Increasing animal/livestock farming on food security
Less efficient than growing crops due to loss of energy from ecosystem between trophic levels. Better yield with vegetables.
80
Impact of new pests and pathogens on food security
Diseases can spread to food (animals as well as plants) which can affect humans who eat it. Destroys crop and harvest. Can be controlled by developing pest-resistant or disease-resistant crops, biological pesticides, removing competition from weeds and diseases using fungicides and herbicides
81
Climate change on biodiversity
Species have to move to new areas with a possible increase in competition for food and shelter. Reduces biodiversity of the area
82
Biomass
Mass of a living material
83
Efficiency of energy transfer in food chains
Energy available to the next stage / energy that was available to the previous stage x 100
84
Importance of water cycle
Water can run out over future generations, living things need it to survive, it is used by humans for things other than drinking e.g. washing, cleaning
85
Process of water cycle
Evaporation from sea, condensation to clouds, precipitation to ground, interception by plants, transpiration from plants to sky, percolation in rock, infiltration in soil, surface run off on ground, ground water through flow in ground
86
Transpiration
Water being given off by plants through the stomata
87
Percolation
Water travelling into permeable rock
88
Desalination
Involves collecting sea water then distilling it by evaporating and condensing it to make it pure
89
Importance of desalination
Helps areas where there is not enough precipitation (droughts). Desalination will give them potable water to drink and use
90
Making potable water
Must be filtered to remove dirt and treated with chemicals such as chlorine to kill pathogens.
91
Detritus feeders
aka detritivores. Feed off dead or decaying material. E.g. woodlice, maggots. Break it up into smaller bits giving it a bigger surface area and speeds up decay
92
Saprophytes
Feed off dead or decaying material by extra cellular digestion. E.g. fungi. They secrete digestive enzymes on the material outside their cells to break it down into smaller bits
93
Food preservation methods to reduce rate of decay
Canning, cooking, freezing, drying, adding vinegar, adding salt or sugar
94
Effect of canning
Airtight. Decomposers kept out
95
Effect of cooling
Slows decay as it slows decomposer's reproduction rate
96
Effect of drying
Decomposers need water to carry out cell reactions
97
Effect of adding salt or sugar
High concentration means they lose water by osmosis which damages the decomposers
98
Effect of adding vinegar
Decomposers die in acid
99
Survival of the fittest in evolution
Evolution by natural selection brings about changes in a species as all organisms have variation: some are advantageous. They compete with others and are more likely to survive. They then reproduce with other organisms and their advantages are passed onto their offspring. This process happens over many generations.
100
Importance of nitrogen
Living organisms need it to make proteins for growth and repair. Plants need nitrates for amino acids to make proteins
101
How do plants take in nitrates?
Active transport through the root hair cells from an area of low concentration (soil) to high (hair cells). They get the energy to do this from respiration
102
Carbon compounds in living organisms
Glucose (respiration), protein (growth and repair), fat (stored energy)
103
Carbon cycle stages
Photosynthesis, respiration of plants, eating, respiration of animals, death, excretion, respiration of decomposers (detritus feeders), fossilisation (by heat and pressure), combustion
104
Carbon found in carbon cycle
Carbon dioxide in air, plants, animals, dead organisms, fossil fuels
105
Carbon in photosynthesis
Plants use carbon dioxide from the atmosphere. Used for molecules such as proteins, fats and carbohydrates
106
Carbon in eating
Stored in fats and proteins. Feed on waste or dead organisms. Passed on.
107
Carbon returning to atmosphere
Animals, plants and microorganisms respire. Combustion of wood, fossil fuels, materials.
108
Carbon in decay
Releases CO2. More in warm, moist conditions with lots of oxygen (involves microorganisms).
109
Nitrogen cycle
Proteins in cells. N2 in air converted to soluble ions absorbed by roots. Passed on to plant then other organisms. Returned to atmosphere as gas
110
Haber process
Industrial chemical process that makes ammonia by reacting nitrogen and hydrogen together (for fertilisers)
111
5 stages of nitrogen cycle
1. Fixation of nitrogen gas to soluble gases such as nitrates (lightning, Haber process to soil, bacteria in root nodules of legumes). 2. Absorbed to roots of plants and stored as proteins. 3. Passed on in food chains and excretion. 4. Death - decomposers break down urea and faeces returning them to the soil as ammonium ions. 5. Releases into atmosphere by denitrifying bacteria that break down nitrates to nitrogen gas
112
Nitrogen-fixing bacteria convert...
Nitrogen gas into soluble ions such as nitrates
113
Nitrifying bacteria covert...
Ammonium ions to nitrate ions
114
Denitrifying bacteria convert...
Nitrate ions to nitrogen gas
115
Nitrogen gas % in atmosphere
78%
116
Lightning fixation
Energy makes nitrogen react with oxygen to form nitrates
117
Decomposer bacteria convert...
Proteins and urea to ammonia
118
Indicator species def
Indicate levels of pollution
119
Indicator species - Air pollution
Black spot fungus (parasite, gains glucose from plant): infect roses in clean air, killed by sulphur pollution. Lichens (mutualist, algae living in fungus): leafy means low pol, crusty men's high pol of sulfur dioxide.
120
Indicator species - Water pollution
(Low in oxygen means polluted). Not polluted: stonefly, freshwater shrimp. Polluted: bloodworms, sludgeworms, mudworms
121
Positives of using indicator species
Easy, quick, cheap, natural (doesn't disrupt environment), doesn't require certain skills, indicates long term pollution levels
122
Negatives of indicator species
Might miss some out, not always present at that time, sensors give better quantitative values (more accurate)
123
Food chain pyramids show either...
Biomass or numbers in population. Biomass is the pyramid but population could be different
124
Calculating percentage of biomass
( Energy transferred to biomass / total energy supplied to organism ) x 100
125
How is energy lost?
Movement, reproduction, excretion
126
Calculate rate of change of decay
1000 / time OR change in volume / time
127
Decomposition def
The breaking down of organic substances (containing carbon) by decomposers such as fungi and bacteria
128
Optimum conditions for decomposers
Warm, moist, lots of oxygen
129
Irradiating food effect
Gamma rays kills decomposers by reducing reproduction rates
130
Stored in oil effect
Removes oxygen
131
Stored in unreactive gas effect
Reduces oxygen
132
Best conditions for composting
Warm (kept outside in sun for decomposers to reproduce, large piles of compost and bin walls insulates heat), moist (kept outside in rain for decomposers to reproduce), oxygen (gaps in compost heat to allow oxygen in so decomposers can reproduce
133
Decomposition def
The breaking down of organic substances (containing carbon) by decomposers such as fungi and bacteria
134
Optimum conditions for decomposers
Warm, moist, lots of oxygen
135
Irradiating food effect
Gamma rays kills decomposers by reducing reproduction rates
136
Stored in oil effect
Removes oxygen
137
Stored in unreactive gas effect
Reduces oxygen
138
Best conditions for composting
Warm (kept outside in sun for decomposers to reproduce, large piles of compost and bin walls insulates heat), moist (kept outside in rain for decomposers to reproduce), oxygen (gaps in compost heat to allow oxygen in so decomposers can reproduce
139
Carbon Cycle
Passed from one organism to the next in complex molecules then returned to the atmosphere as carbon dioxide
140
Where is carbon found?
Carbon dioxide in air. Carbon in animals. Carbon in plants. Carbon in dead organisms. Carbon in fossil fuels
141
Habitat
Where an organism lives
142
Using a quadrat to look at species richness, you would...
Count the total number of different species (not individuals within a species)
143
Using a quadrat to find out the percentage cover (to estimate plant frequencies)
Look at the percentage of a quadrat covered by one species
144
Sweep nets
Catch flying insects. Large nests used to sweep through grasses or leaves of trees
145
Kick sampling
Samples stream invertebrates. Nets are held downstream of an area of river bed and is gently disturbed by the person doing the sampling so the animals float into the net
146
Pitfall traps
Catch small mammals. A hole dug into the ground with food inside to attract them and has smooth sides to prevent mammals escaping
147
Pooters
Small devices used to sample small insects in trees by sucking them up safely without them getting into your mouth
148
Systematic sampling
Used if there is a trend or pattern across a habitat (abiotic factors e.g. temperature fluctuations, light intensity, immersion by water)
149
Kite diagrams
Present data from belt transects. Width of the bar from the middle shows how many individuals were observed at that point. Distance at x axis
