Ecosystems Flashcards
1
Q
What is an adaptation?
A
How the organism is suited to a particular condition
2
Q
What is an ecosystem?
A
All the organisms and the environment they live
3
Q
What is community?
A
All the different organisms that live in an ecosystem
4
Q
What is population?
A
The number of one type of species
5
Q
What is distribution?
A
Where the organisms are found in an ecosystem
6
Q
What is abundance?
A
How common something is in an area
7
Q
What is a habitat?
A
A place in which an organism lives e.g. forest
8
Q
What is a food web?
A
Shows the feeding relationship between organisms in an community
9
Q
What is a producer?
A
An organism that produces its own food I.e. plants
10
Q
What is a resource?
A
The things an organisms need to stay alive I.e water, food, shelter and light
11
Q
What is a consumer?
A
Needs to eat other organisms to survive
12
Q
What does the arrow show in a food web?
A
The flow of energy
13
Q
What is a tropic level?
A
Any class of organisms that occupy the same position in a food chain, as primary consumers, secondary consumers and tertiary consumers.
14
Q
What is interdependence?
A
When organisms need each other for resources
15
Q
What measures the abundance of plants?
A
A quadrat
16
Q
How is it placed along the transect?
A
At regular intervals and count number of species
17
Q
How is the whole population estimated?
A
Estimated =. Average number. X. Total area
population of species Being studied
18
Q
What is energy from the sun transferred into?
A
Plant biomss
19
Q
Where is it then transferred?
A
To consumers when they eat it
20
Q
How is energy lost at every stage(wasted along food web)
A
By heat, kinetic energy, lost through fasces and urine e.t.c, transferred to surroundings
21
Q
How do you calculate efficiency?
A
Efficiency =. Total useful energy transferred
—————————————
Total energy supplied
22
Q
What are abiotic factors?
A
Non-living factors or conditions that can influence a plant or animal distribution.
23
Q
What are some examples of abiotic factors?
A
Light intensity pH Amount of rainfall/water Nutrient level Temperature Pollutions
24
Q
How does low temperature affect plant growth?
A
Enzyme controlled reactions are slower
25
How does a low mineral ion content of soil, affect plant growth
Reduces the amount of some substances e.g. proteins, that the plant can make
26
How does a low water content of soil affect plant growth?
Reduces reaction rates because most reactions in cells take place in solution
27
How do low light levels affect plant growth?
Reduces the amount of energy the plant receives for photosynthesis
28
How can drought (in an ecosystem) have a long-term effect on the animals in a community
Lack of water reduces reaction rates because most reactions in cells take place in a solution.
This prevents animals from growing
They can’t be independent
This disrupts the food web and leaves little food for carnivores
29
How can you measure:
- Light Intensity
- Soil moisture
- Temperature?
Light intensity - light probe (stuck in ground)
Soil moisture - put soil pH in ground
Temperature - use a thermometer
30
What is the method for the Core Practical: Quadrats and transects
1) Put a long tap measure along the ground starting where there is no shade until there is a lot of shade. (This is the transect line)
2) Make Measurements at regular intervals along the transect line
3) Place the top left-hand corner of the quadrat at a measurement point on the transect line
4) Measure the abiotic factors at that point and record them
5) Record the abundance of your selected plants in the quadrat
6) Repeat steps 3 to 5 at each measurement along the transect
31
What are biotic factors?
Organisms in an ecosystem that affect other living organisms
32
What can introducing a new predator affect?
It increases competition for other predators animals
| Abundance in prey will decrease because there is a new predator to kill and eat them as a result of predation
33
What is a predator-prey cycle?
When (in small communities) the number of predators and it’s prey are closely related
34
How can new habitats increase biodiversity?
New habitats allow new species to grow in the area, increasing the biodiversity (number of different species)
35
How can some lichens be used as an indicator species for pollution?
Only the lichen can tolerate air that is polluted with sulfur (that contains gases from burning fossil fuels)
Therefore, they can indicate when there is sulfur dioxide pollution
36
What is Blackspot Fungus?
A pathogen of roses and doesn’t survive well when there is a lot of sulfur pollution. Therefore, a lot of roses rarely suffer from blackspot fungus in the city. (A lot of pollution in city)
37
What can cause water pollution?
Poisonous substances released by factories e.g detergents or fertilisers and sewage
38
What does eutrophication encourage?
Rapid growth of algae
39
What indicator species are adapted to water with low pollution levels?
Stonefly nymph and dragonfly nymph
40
What indicator species are adapted to high levels of pollution?
Bloodworm and sludge worm
41
How is pollution measured?
Using sensors
42
What is a parasite?
An organism that feeds on another organism (called a host) The host is always harmed in the relationship whereas the parasite benefits I.e. get food from the blood whereas the host loses blood.
43
What are examples of parasites?
Flea
Tapeworm
Hookworm
44
How are mistletoe and tapeworms parasites?
Mistletoe: Attach to host plants (tree) and absorb nutrients from the branches
Tapeworm: Live inside host body and absorb nutrients from the intestines
45
What is a mutualistic relationship?
When both organisms benefit from the relationship
46
How are nitrogen fixing bacteria and plants a mutualistic relationship?
.
Bacteria gets a home and the plant gets nitrogen
47
What is biodiversity?
The variety of organisms or species in an environment
48
How can we affect biodiversity?
```
Hunting/poaching
Deforestation
Pollution
Building on land
Introducing new species
Genetically modifying species
```
49
What has overfishing done?
Damaged ecosystems
50
What are some benefits of fish farming?
Helps the wild fish to recover
They’re better fed and grow faster
The fish are protected against predators and disease
51
What are some problems of farm fishing?
Uneaten food and faeces sink to bottoms and can change conditions or harm wild organisms
Therefore, oxygen levels can drop
Parasites and disease spread a lot more easier
52
What is a biological control?
Introducing a species into an area to help control pests or weeds
53
What is an example of a biological control?
The cane toad was introduced to control the cane beetle.
| But these toads have killed native animals and are poisonous
54
What is eutrophication?
When you add more nutrients (fertilisers) to an ecosystem than it normally has
55
How can eutrophication harm an ecosystem ?
1) Farmers use fertilisers on fields
2) Rain can wash off the excess nitrate into streams or rivers and lakes
3) High levels of nitrate causes high levels of algal growth on the surface of the water
4) Plants in the lake can no longer photosynthesise because light is being blocked form the algae on surface which causes the plant to die.
5) Bacteria/fungi decompose the dead plants
6) The Bacteria and fungi use the oxygen which cause the oxygen levels to drop, which causes the fish to die and there is no longer enough oxygen available for the fish/animals.
56
What is conservation?
When an effort is made to protect an endangered or rare species o habitats e.g. breeding programs in zoos, reforestation
57
How do habitats help preserve biodiversity?
Rebuilding them and protecting them
| Linking the habitats to their species allow them to roam and find a mate
58
What can good biodiversity help do?
Areas with greater biodiversity recover faster from natural disasters
Plants and animals can be used for food and medicine
59
What does food security mean?
Means having access to enough safe and healthy food at all times
60
Why is food security getting worse/bad in poorer countries?
There’s not enough food available because the population is increasing at a non-renewable rate
61
Why is growing food from crops causing problems (especially with agricultural inputs)?
To make crops grow bigger, fertiliser is used. Over the last few years, more and more fertiliser is being used.
Fertilisers are made with chemical processes that release carbon dioxide and need energy. This can harm the environment so people don’t think this is sustainable
62
What is sustainability?
If a process is sustainable, it is possible to continue it at the same level without causing harm to the environment or food security
63
What can increasing carbon emissions lead to?
Climate change
64
What can climate change cause considering pests?
Some vectors/pests like midgets get killed by cold temperatures. So, due to climate change the world will get warmer so less midges are being killed so more cows and sheep e.t.c are at risk of bluetounge disease
65
What is one ideas on how to reduce carbon emissions?
Growing plants for biofuel to replace fossil fuels
66
Why are biofuels more sustainable?
We can supply them at a rate of us using them. Aka they are renewable compared to fossils fuels which are non renewable
67
What is the water cycle?
The sun uses energy to heat up the water and sea, causing it to evaporate. The clouds collect the water vapour and condense the water, causing precipitation. The precipitation/rain collects in rivers and streams.
68
What is potable water?
Water that is clean and safe for drinking
69
How can we use fog harvesting to obtain potable water?
Nets are used to catch water droplets/condensate from clouds or mist in some desert areas. As long as the equipment is clean, the water needs no treatment to make it potable.
70
How do you use a solar still to obtain potable water?
Impure water is contained outside the collector, where it is evaporated by energy from the sun which shines through clear plastic or glass. The pure water vapour condensed on the cool inside surface, and drips down where it is collected and removed.
71
How is desalination used to obtain potable water?
Desalination is where they removes salts and other minerals (by distillation) to create fresh, drinkable water where fresh water is limited but have a big supply of seas water.
It uses a lot of energy.
72
What can increase carbon dioxide levels?
Deforestation
Pollution
Burning fossil fuels = combustion
73
What can decrease carbon dioxide levels?
Photosynthesis
74
What is the equation for combustion?
Fuel + oxygen ———> Carbon dioxide + water
75
What is the equation for respiration?
Oxygen + glucose ———> Carbon dioxide + water
76
What is the carbon cycle?
Carbon is found in the atmosphere at 0.04%
This carbon is absorbed into a plant by photosynthesis
The plant is then consumed (turns into biomass) by insects and small animals.
Their faeces are also eaten by decomposers like fungi, insects e.t.c which puts carbon into the atmosphere again
The plants and animals can also respire, putting carbon back into the atmosphere.
Also, the plant can be turned into fossil fuels which is combusted, releasing more carbon into the atmosphere
77
What is nitrogen used in?
In amino acids and making protein
| Also used in DNA
78
What does it mean if a plant is deficient in nitrogen?
It doesn’t have enough/is lacking some
79
How much nitrogen is in the air?
78%
80
What is nitrogen needed as?
Nitrates and ammonia for plants to use
81
What are the roles of bacteria in the nitrogen cycle?
Bacteria are found in the soil as decomposers
The bacteria release nitrogen compounds when they decompose with dead plants and animals and their waste
Nitrogen-fixing bacteria can convert nitrogen gas to nitrogen compounds
The bacteria provides the plants with nitrogen compounds
In return, the plant provides protection -> mutualistic relationship I.e legume plants
Denitrifying bacteria
Break down urea and proteins into nitrates in the soil
82
What is decomposition?
Process of rotting (breaking down)
83
What decomposes stuff?
Decomposers e.g. bacteria and fungi
84
What are the best conditions for decomposers?
Warm
Damp + moist
Oxygen
85
How can we preserve food?
Reduce the temperature
Reduce the moisture + water content (salting and drying)
Irradiation of packed foods
Reducing oxygen e.g. nitrogen packaging
86
What is the rate of decomposition?
Mass lost
—————
Time
87
Why must a compost be moist?
It’s the best condition for decomposers
88
Why must a compost have layers of soil between the different layers?
Allows decomposers to release nitrogen compounds when they decompose with the plant material as worms and fungi is already in
89
Why must compost be sprinkled with composting agent?
Allows compost to gain nitrogen which helps plants to grow bigger
90
Why must you cover the compost?
It keeps heat in and avoids rain which is good as high temperatures are the best conditions for decomposers as it doesn’t dry out the bacteria
91
Why must you turn the compost over every now and again?
Turning over oxidase the whole pile, compost is used which adds nutrients
