Ecology Flashcards
1
Q
What is meant by the term ‘habitat’?
A
the place where an organism lives
2
Q
What is meant by the term ‘population’?
A
all the organisms of one species living in a habitat
3
Q
What is meant by the term ‘Community’?
A
The populations of different species living in a habitat
4
Q
What is meant by the term ‘abiotic factors’?
A
Non-living factors of the environment
5
Q
What is meant by the term ‘biotic factors’?
A
living factors of the environment
6
Q
What is meant by the term ‘ecosystem’?
A
the interaction of a community of living organisms with abiotic parts of their environment
7
Q
What do plants compete for?
A
light, space, water, mineral ions
8
Q
What do animals compete for?
A
territory, food, water, mates
9
Q
True of false: No change in any environment can have a knock-on effect.
A
False, any change in any environment can have a knock-on effect
10
Q
What are stable communities?
A
when all of the species and environmental factors are in balance so that the population sizes are roughly constant
11
Q
What two changes in abiotic factors could affect plant populations?
A
- A decrease in light intensity, temperature or CO2 concentration would decrease the rate of photosynthesis. This could affect plant growth and cause a decrease in population size
- A decrease in mineral content of the soil could cause nutrient deficiencies, affecting plant growth
12
Q
What is interdependence?
A
In a community, each species depends on other species for things such as food, shelter, pollination and seed dispersal
13
Q
What biotic factors may affect organisms in an ecosystem?
A
- New predators
- Competition
- New pathogens
- Availability of food
14
Q
Complete the sentence: Adaptations allow organisms to __________.
A
survive
15
Q
What are the three types of adaptations?
A
Structural
Behavioural
Functional
16
Q
What are structural adaptations?
A
Features of an organism’s body structure.
E.g.
- camouflage fur/skin
- thick skin to trap heat
- thin layer of fat to reduce heat
- surface area to volume ratio
17
Q
What are behavioural adaptations?
A
The way organisms behave
E.g.
- many species migrate in response to climates changing throughout the year
18
Q
What are functional adaptations?
A
Adaptations on the inside of an organism’s body that can be related to processes such as reproduction and metabolism.
E.g.
- animals that conserve water produce little sweat and small amounts of urine
- some animals hibernate and lower their metabolism to conserve energy
19
Q
Why do microorganisms have a huge variety of adaptations?
A
so that they can live in a wide range of environments
20
Q
What are microorganisms that are adapted to live in very extreme conditions called?
A
extremophiles
21
Q
What do food chains show?
A
What is eaten by what in an ecosystem
22
Q
What do food chains always start with?
A
A producer
23
Q
What are producers?
A
Organisms that make their own food using energy from the Sun.
They are often green plants or algae that make glucose by photosynthesis.
24
Q
What is glucose used to make in plants?
A
Other biological molecules in the plant
25
What is biomass?
The mass of living material
26
When is energy transferred through living organisms in an ecosystem?
When organisms eat other organisms
27
What are producers eaten by?
Primary consumers
28
What are primary consumers eaten by?
Secondary consumers
29
What are secondary consumers eaten by?
Tertiary consumers
30
What is the population of any species usually limited by?
The amount of food available
31
If the population of the prey increases, what else will increase?
The population of the predators
32
As the population of predators increases, what will decrease?
The number of prey
33
True or false – Predator-prey
cycles are always out of phase with each other.
True
34
Why are predator-prey cycles always out of phase with each other?
It takes a while for one population to respond to changes in the other population.
35
What does environmental variation affect?
The distribution of organisms
36
What is the distribution of an organism?
Where an organism is found
37
What are the two ways to study the distribution of an organism?
1. Measure how common an organism is into sample areas and compare them
2. Study how the distribution changes across an area (by placing quadrat along a transect)
38
What did the two ways to study the distribution of an organism give?
Quantitative data
39
Describe how a quadrat can be used to study the distribution of small organisms.
1. Use two 10m tape measures and place them perpendicular to each other at one end. Divide the area into a grid.
2. Use a random number generator to pick coordinates.
3. Place the 1 m² quadrat at the coordinates and count all the organisms within the quadrat.
4. Repeat steps 2 and 3 as many times as you can.
5. Work out the main number of organisms per quadrat within the first sample area.
6. Calculate the population size of an organism by multiplying the mean by the total area of the habitat.
7. Repeat in a second sample area and then finally compare the two population sizes.
40
Describe how a transect can be used to study the distribution of organisms.
1. Mark out a line in the area you want to study with a 10m tape measure.
2. Collect data along the line by using a quadrat at regular intervals.
3. Compare the number of organisms in each quadrat.
41
Describe how you can estimate the percentage cover of a quadrat.
1. Count the number of squares covered by organism A.
2. Make this into a percentage by dividing the number of squares covered by the organism by the total number of squares in the quadrat then multiply the result by 100.
3. Do the same for organism B.
42
What are three environmental changes that affect the distribution of organisms?
1. Temperature.
2. Availability of water.
3. Composition of atmospheric gases.
43
How can temperature affect the distribution of organisms?
A rise in average temperature could cause species to migrate to other areas.
44
How can availability of water affect the distribution of organisms?
The distribution of some animal and plants species change between the wet and dry seasons.
45
How can the composition of atmosphere gases affect the distribution of organisms?
In areas of high air pollution, some species cannot grow or the distribution of species changes.
46
What can environmental changes be caused by?
Seasonal factors
Geographic factors
Human interaction
Global warming
47
What is the water cycle?
How water is endlessly recycled.
48
Describe the process of the water cycle.
1. Energy from the Sun makes water evaporate from the land and see turning it into water vapour water also operates by transpiration.
2. Water vapour is carried upwards. When it gets higher up, it cools down and condenses to form clouds.
3. What a fools from clouds as precipitation onto land where it provides freshwater for plants and animals.
4. It then drains into the sea before the whole process starts again.
49
What are the four key terms involved in the water cycle?
Evaporation
Transpiration
Condensation
Precipitation
50
What are elements cycled back to the start of the food chain by?
Decay
51
How is biomass returned to the environment?
In waste products when the organisms die and decay
52
How is biomass returned to the environment?
In waste products when the organisms die and decay
53
What conditions increase the rate of decay?
Warm, moist aerobic condition because microorganisms are more active in these conditions.
54
What is the constant cycling of carbon called?
The carbon cycle
55
What is carbon dioxide removed from the atmosphere by?
Green plants and algae during photosynthesis
56
What is carbon dioxide removed from the atmosphere by?
Green plants and algae during photosynthesis
57
When the plants and algae are eaten by animals, what becomes a part of the fat and proteins in the bodies?
Carbon
58
What are detritus feeders?
Animals that feed on the remains of animals or plants
59
What gas does respiration release?
Carbon dioxide
60
What is animal waste broken down by?
Detritus feeders and microorganisms
61
What does the combustion of wood and fossil fossil fuels release?
Carbon dioxide
62
What is compost?
Decomposed organic matter that is used as a natural fertiliser for crops and garden plants
63
What can produce compost?
Decomposition
64
What is the process of decay also called?
Decomposition
65
What is the rate of decay affected by?
Temperature
Water availability
Oxygen availability
Number of decay organisms
66
What is responsible for decomposition?
Microorganisms such as bacteria and fungi as well as the detritus feeders.
67
Why do rainforest ecosystems usually have a very high rate of decay?
Because they have high temperatures and moist environments
68
How does temperature affect the rate of decay?
Warm temperatures increase the rate the enzymes involved in decomposition work at.
If temperatures are too high, decomposition slows down as enzymes are denatured and the organisms die.
Cold temperatures slow the rate of decomposition .
69
How does water availability affect the rate of decay?
Moist environments result in a faster rate of decay as the organisms involved need water to carry out biological processes.
70
How does oxygen availability affect the rate of decay?
In aerobic decay microorganisms need oxygen to respire.
71
How does the number of decay organisms affect the rate of decay?
The more microorganisms and detritus feeders there are faster decomposition happens
72
What is biogas made by?
Anaerobic decay of waste material.
73
What produces biogas?
Many different microorgansims
74
What does anaerobic decay produce?
methane
75
What is biogas made in?
A simple fermenter called a digester or generator
76
Why do biogas generators need to be kept at a constant temperature?
to keep the microorganisms respiring
77
Why can’t biogas be stored as a liquid?
It needs too high a pressure
78
What are the four things that biogas is used for?
- heating
- cooking
- lighting
- powering a turbine to generate electricity
79
What are the two main types of biogas generator?
Batch generators
Continuous generators
80
What are batch generators?
They make biogas in small batches.
They are manually loaded with waste, which is left to digest.
The by-products are cleared away at the end of each session.
81
What are continuous generators?
They make biogas all the time.
Waste is continuously fed in and biogas is produced at a steady rate.
They are more suited to large-scale biogas projects.
82
What do all biogas generators need to have?
1. an inlet for waste material to be put in
2. an outlet for the digested material to be removed through
3. an outlet so that the biogas can be piped to where it is needed
83
How can you investigate the affect of temperature on decay? RP
1. Measure out 5 cm³ of lipase solution and add it to a test tube. Label this tube ‘L’.
2. Measure out 5 cm³ of milk and add it to a different test tube.
3. Add 5 drops of phenolphthalein indicator to the tube containing milk.
4. Then measure out 7 cm³ of sodium carbonate solution and add it to the tube containing milk mixture. This would turn the solution pink (alkaline).
5. Put both tubes into a water bath set to 20°C and leave them to react the temperature. Use a thermometer to check this.
6. Then use a calibrated dropping pipette to put 1cm³ of the lipase solution into the milk mixture and start a stopwatch.
7. Stir the contents, the enzyme will start to decompose the milk.
8. When the solution turns colourless, stop the stopwatch and record how long the colour change took.
9. Repeat the experiment at a range of different temperatures (e.g. 30°C, 40°C, 50°C). Carry out the experiment three times at each temperature to calculate a mean time taken for the colour change.
10. Calculate the rate of decay (units in s^-1)
84
What is the equation for rate?
Rate = 1000/ time
85
What is the unit for rate?
s^-1
86
What is biodiversity?
The variety of different species of organisms on earth, or within an ecosystem.
87
True or false: High biodiversity is important.
True
88
Why is high biodiversity important?
It makes sure that ecosystems are stable due to interdependence and how species may also help to maintain the right physical environment for each other.
89
What are three human actions that are reducing biodiversity?
waste production
deforestation
global warming
90
Why is the world population growing?
Modern medicine and farming methods have reduced the number of people dying from disease or hunger.
91
Complete the sentence: Our increasing population puts ______________ on the environment.
pressure
92
What is resulting in raw materials being used up quicker than they can be replaced?
a demand for a higher standard if living requires more luxuries, so more energy and resources to create them
93
As we make more and more things, what do we produce more of?
waste, including waste chemicals
94
If waste is not properly handled, what will be caused?
more harmful pollution
95
What waste is in water?
Sewage and toxic chemicals from industry
Chemicals used on land can be washed into water
96
What waste is in land?
Toxic chemicals used for farming
Nuclear waste buried underground
Household waste in landfill
97
What waste is in the air?
Smoke and acidic gases
e.g. sulfur dioxide produces acid rain
98
Describe the greenhouse effect.
Energy from the sun heats the earths atmosphere and surface. Heat radiation is trapped by greenhouse gases which absorb the energy and re-radiate it in all directions. Some radiation is radiated back out into space.
99
What are the three greenhouse gases?
Carbon Dioxide
Methane
Water vapour
100
What are the four consequences of global warming?
Sea levels rising
Changes in species distribution
Changes in migration patterns
Reduction in biodiversity
101
How can global warming cause sea levels to rise?
Higher temperatures cause seawater to expand and ice to melt, causing the sea level to rise
102
How can global warming lead to changes in species distribution?
When temperatures increase and rainfall patterns change, some species become more widely or less widely distributed.
103
How does global warming lead to changes in migration patterns?
Some birds will migrate to warmer areas such as the north
104
How does global warming lead to a reduction in biodiversity?
Some species are unable to survive in a changed climate so become extinct
105
What do humans use land for?
Building, quarrying, farming and disposing of waste
106
What does destroying peat bogs do to the atmosphere?
Adds more carbon dioxide
107
What are peat bogs?
bogs are areas of land that are acidic and waterlogged, when plants die in these areas they don’t fully decay so they build up to form peat
108
How are peat bogs, carbon stores?
They store carbon from dead plants as they do not decay
109
What can peat be used for?
fuel or compost
110
How does the destruction of peat bogs release carbon dioxide?
- when drained, microorganisms start to decompose it, they respire to produce carbon dioxide
- when burned it releases carbon dioxide
111
How can the destruction of peat bogs lead to a decrease in biodiversity?
It is destroying the habitat for animals, plants and microorganisms that live there
112
What is deforestation?
The cutting down of forests.
113
What is deforestation used for?
- to clear land for farming, to provide more food
- to grow crops from which biofuels can be produced
114
What are the three problems that deforestation causes?
- Less carbon dioxide removed from atmosphere
- More carbon dioxide in the atmosphere
- Less biodiversity
115
What are the four ways to protect ecosystems and biodiversity?
1. Breeding programmes
2. Habitat protection
3. Preventing global warming
4. Reducing waste
116
What are breeding programmes set up for?
To prevent endangered species from becoming extinct
117
What are breeding programmes?
Where animals are bred in captivity to make sure the species survives if it dies out in the wild.
Individuals can sometimes be released into the wild to boost or re-establish a population.
118
What are habitat protection programmes used for?
To protect and regenerate rare habitats like mangroves, heathland and coral reefs.
It helps to protect and preserve the ecosystem and biodiversity.
119
What is an example of habitat protection programmes?
Reintroducing hedgerows and field margins on fields in farms where they grow only a single type of crop. Field margins allow wild flowers and grasses to grow around the edges of fields. They provide a habitat for a wider variety of organisms.
120
Who have introduced regulations and programmes to reduce the level of deforestation and carbon dioxide emissions?
Some governments
121
What can be done to reduce waste?
- encouraging people to recycle and reduce the amount of waste that goes into landfill
- encouraging people to buy what they need
- reusing certain items
122
What are the four conflicting pressures that affect how biodiversity is maintained?
1. The cost of programmes
2. The effect on the local economy
3. Protecting food security
4. The development of society
123
Why is the cost of maintaining biodiversity programmes an issue?
Money may be prioritised for other things.
It costs a lot to maintain and monitor programmes.
124
Why does the maintaining of biodiversity have an effect on the local economy?
- Costly
- Could cause a reduction in jobs (tree-felling)
- Could cause people to move away to find work
125
Why is protecting food security an issue when it comes to maintaining biodiversity?
Certain pests and organisms must be killed by farmers to protect crops, however this could affect the food chain and biodiversity.
126
Why is the development of society an issue when it comes to maintaining biodiversity?
Sometimes land is in such high demand that greenfield sites must be used for development.
127
What can food chains be divided into?
Trophic levels
128
What are trophic levels?
Different stages of the food chain that consist of one or more organisms that perform a specific role in the food chain.
129
What is in trophic level 1?
Producers
130
What are in tropic level 2?
Primary consumers
131
What are in tropic level 3?
Secondary consumers
132
What are in tropic level 4?
Tertiary consumers
133
How do bacteria and fungi decompose dead animal or plant material left in an environment?
They secrete enzymes that break down the dead stuff into small soluble food molecules.
134
Complete the sentence: There is _______ energy and ______ biomass every time you move up a trophic level.
less, less
135
What do pyramids of biomass show?
The relative masses of trophic levels
136
When drawing pyramids of biomass, what must be labeled?
each bar
137
True or false: Biomass is gained between each trophic level.
False - Biomass is lost.
138
Why is biomass lost between the trophic levels?
- Organisms don’t always eat every single part of the organism they are consuming
- They don’t absorb all of the biomass that they ingest so it is excreted.
- Some biomass is converted into other substances that are lost as waste (carbon dioxide, urea)
139
How can you calculate the biomass lost between each level?
Subtract the biomass that is available at that level from the biomass that was available at the previous level
140
How can you calculate the efficiency of biomass transfer?
efficiency = biomass transferred to the next level / biomass available at previous level
141
What is food security?
Having enough food to feed a population.
142
What things can threaten food security?
- Increasing world population
- Diet changes in developing countries
- Farming being affected by new pests and pathogens or changes in environmental conditions
- High input costs of farming
- Conflict that affects the availability of food and water
143
Why are sustainable methods of food production needed?
So that enough food can be made for everyone now and in the future.
144
What is sustainable production?
Making enough food without using resources faster than they can be renewed
145
What is overfishing decreasing?
fish stocks
146
What are the effects of overfishing?
- fewer fish to eat
- ocean’s food chain is disrupted
- some species disappearing from areas
147
What are the two ways that fish stocks can be maintained?
Fishing quotas
Net size
148
What are fishing quotas?
Limits on the number and size of fish that can be caught in certain areas. This allows them to reproduce so that the population can grow.
149
What is net size?
Limiting the mesh size of the fish net, depending on what is being fished. This reduces the amount of unwanted and discarded fish.
Using a larger mesh size will let unwanted species escape. Therefore younger fish will also escape allowing them to breed.
150
How can food production be made more efficient?
Limiting the movement of livestock in a temperature controlled environment. This means that the animal uses less energy moving and controlling their body temperature, so more energy is available for growth and more food can be produced.
151
What does it mean if an animal is factory farmed?
They are raised in small areas to reduce their movement so that more energy is available for growth. Some are also fed high-protein foods.
152
Why are factory farming methods controversial?
- Disease can spread quickly between animals that are kept closely together
- Some people believe it is cruel and unnatural.
153
What is biotechnology?
Where living things and biological processes are used and manipulated to produce a useful product.
154
What can bacteria be engineered to produce?
human insulin
155
Describe how bacteria can be genetically engineered to make human insulin.
1. A plasmid is removed from a bacterium.
2. The insulin gene is cut out of a human chromosome using a restriction enzyme.
3. The cut in the DNA leaves one of the DNA strands with unpaired bases, called a ‘sticky end’.
4. The plasmid is cut open using the same restriction enzymes, leaving the same sticky ends.
5. The plasmid and insulin gene are mixed together.
6. Ligase is added, joining the sticky enzymes to produce recombinant DNA.
7. The recombinant DNA is inserted into a bacterium.
8. The modified bacterium is grown in a vat under controlled conditions.
9. This produces millions of bacteria that produce insulin.
10. The insulin is harvested and purified to treat people with diabetes.
156
What is mycoprotein?
Made from fungi to make high-protein meat substitutes for vegetarian meals
157
How is mycoprotein produced?
The fungus Fusarium is grown in aerobic conditions on glucose syrup.
The fungal biomass is harvested and purified to produce mycoprotein.
158
Why are some crops genetically modified?
- To be resistant to pests
- To grow better in changing conditions
- To provide more nutritional value
159
What is ‘Golden rice’?
A food that has been genetically modified to produce a chemical that is converted in the body to vitamin A.
160
Why do some people not agree with genetically modifying food?
- Many people argue that people are hungry because they can’t afford food, not because there isn’t any.
- Some countries could become dependent on companies that sell GM seeds
- Sometimes poor soil is the reason that crops don’t grow, so even GM crops won’t survive
