Ecology Flashcards
1
Q
Explain water cycle
A
- Energy from the sun makes water evaporate from the land and sea, turning it into water vapour
- Water also evaporates from plants - this is knows as transpiration
- The warm water vapour is carried upwards. When it gets higher up it cools and condenses to form clouds
- Water falls from the clouds as precipitation onto land, where it provides fresh water for plants and animas
- Some of this water is absorbed by the soil and is taken up by plant roots. This provides plants with fresh water for things like photosynthesis. Some of the water taken up by plants becomes part of the plant’s tissues and is passed along to animals in food chains
- Like plants, animals need water for the chemical reactions that happen in their bodies. Animas return water to the soil and atmosphere through excretion
- Water that doesn’t get absorbed by the soil will runoff into streams and rivers
- From here, the water then drains back into the sea, before it evaporates all over again
2
Q
Explain the carbon cycle
A
- CO2 is removed from the atmosphere by green plants and algae during photosynthesis. The carbon is used to make glucose, which can be turned into carbohydrates, fats and proteins that mark up the bodies of the plants and algae
- Wen the plants and algae respire, some carbon is returned to the atmosphere as CO2
- When the plants and algae are eaten by animals, some carbon becomes part of the fats and proteins in their bodies. The carbon then moves through the food chain
- When the animals respire, some carbon is returned to the atmosphere as CO2
- When plants, algae and animals die, other animals and microorganisms feed on their remains. When these organisms respire, CO2 is retuned to the atmosphere
- Animals also produce waste that is broken down by detritus feeders and microorganisms
- The combustion of wood and fossil fuels also releases CO2 back into the air
- So the carbon is constantly being cycled - from the air, through food chains and eventually back out into the air again
3
Q
What is an abiotic factor
A
Non-living factor
4
Q
Examples of abiotic factors
A
- moisture level
- light intensity
- temperature
- carbon dioxide level (for plants)
- wind intensity and direction
- oxygen level (for aquatic animals)
- soil pH and mineral content
5
Q
What is a biotic factor
A
Living factors
6
Q
Examples of biotic factors
A
- new predators
- competition
- new pathogens
- availability of food
7
Q
Example of a change in environment for abiotic factors (light intensity)
A
- a decrease in light intensity, temperature or level of carbon dioxide could decrease rate of photosynthesis in a plant species
- this could affect plant growth and cause a decrease in the population size
- animals depend on plants for food so a decrease in plant population could affect the animal species in a community
8
Q
Examples of change in environment of biotic factors (squirrels)
A
- red and grey squirrels live in the same habitat and eat the same food
- grey squirrels outcompete the red squirrels so the population of red squirrels is decreasing
9
Q
What is a habitat
A
The place here an organism lives
10
Q
What is a population
A
All the organisms of one species living in a habitat
11
Q
What is a community
A
The populations of different species living in a habitat
12
Q
What is an ecosystem
A
The interaction of a community of living organisms (biotic) with non-living (abiotic) parts of their environment
13
Q
What do plants need from their environment and from other organisms in order to survive and reproduce
A
Light
Space
Water
Mineral ions from soil
14
Q
What do animals need from their environment and from other organisms in order to survive and reproduce
A
Space (territory)
Food
Water
Mates
15
Q
What is interdependence
A
- in a community, each species depends on other species for things such as food, shelter, pollination and send dispersal
16
Q
What happens to the interdependence in a ecosystem if theres a major change in the ecosystem
A
It can have massive effects
17
Q
3 different types of adaptations
A
Structural
Behavioural
Functional
18
Q
Structural adaptations
A
- these are features of an organism’s body structure such as shape or colour
- arctic fox: white fur to camouflage them with the snow to avoid predators and sneak up on prey
- wales: live in cold places so they have thick layer of blubber and a low surface to area to volume ratio to help them retain heat
- camels: live in ho places so have a thin layer of fa and a large surface area to volume ratio to help them lose heat
19
Q
Behavioural adaptations
A
- these are the ways that organisms behave
- many species migrate to warmer climates during the winter to avoid the problems of living in cold conditions
20
Q
Functional adaptations
A
- these are things that go on inside an organisms body tha can be related to processes like reproduction and metabolism
- desert animals conserve water by producing very little sweat and small amounts of concentrated urine
- brown bears hibernate over winter. They lower their metabolism which conserves energy, so they don’t have to hunt when theres not much food about
21
Q
What are extremophiles
A
- microorganisms that are adapted to live in very extreme conditions
- for example some ca live at high temperatures and others can live in places with a high salt concentration or at high pressure
22
Q
Order of food chain
A
Producers — primary consumers — secondary consumer — tertiary consumers
23
Q
What is a producer
A
Make their own food using energy from the sun
24
Q
What’s a biomass
A
The mass of living material
25
What happens when a green plant produces glucose
- some of it is used to make other biological molecules in the plant
- these biological molecules are the plants biomass
- biomass can be thought of as energy stored in a plant
- energy is transferred through living organisms in an ecosystem when organisms eat other organisms
26
What is a predator
A consumer that hunts and kill other animals
27
What is a stable community with prey and predators like
1. The population of any species is usually limited by the amount of food available
2. If the population of the prey increases, then so will the population of the predators
3. However, as the population of predators increases, then so will number of prey will decrease
4. The predator-prey cycle is always out of phase with each other because it takes a while for one population to respond to changes in the other population.
28
Using quadrats to study the distribution of small organisms in 2 sample areas
1. Place a 1m^2 quadrant on the ground at a random point within the first sample area (divide the area into a grid and use a random number generator to pick coordinates)
2. Count all the organisms within the quadrat
3. Repeat steps 1 and 2 as many times as you can
4. Work out the mean number of organisms per quadrat within the first sample area (total number of organisms/ number of quadrats)
5. Repeat steps 1-4 in the second sample area
6. Finally compare the 2 means
29
How to work out population size of 1 area
Multiply mean number of organisms by total area of habitat
30
What is the distribution of an organism
Where an organism is found
31
What is distribution of an organism affected by
Abiotic and biotic factors
32
When to use transect
To help find out how organisms are distributed across an area
33
How to use a transect
1. Mark out a line in the area you want to study using tape measure
2. Collect data along the line
3. You can do this by just counting all the organisms you’re interested in that touch the line
4. Or, you can collect data by using quadrats. These can be placed next to each other along the line or at intervals, for example every 2meters
34
How to estimate percentage cover of a quadrat
1. Count number of squares covered by organisms A
2. Make this into a percentage (divide by 100)
3. Do the same for any other organisms
35
What is biodiversity
The variety of different species of organisms on earth,, or within an ecosystem
36
Why is high biodiversity important
- it makes sue that ecosystems are stable because different species depend on each other for things like shelter and food
- different species can also help maintain the right physical environment for each other
37
What human actions reduce biodiversity
Waste production
Deforestation
Global warming
38
Why is the human population rising so much
- modern medicine
- farming methods
- they have reduced the number of people dying from disease and hunger
39
Water pollution
- sewage and toxic chemicals from industry can pollute lakes, rivers and oceans
- this affects the plants and animals that rely on them for survival
- and the chemicals used on land can be washed into water
40
Land pollution
- we use toxic chemicals for farming
- we also bury nuclear waste underground, and we dump a lot of household waste in landfill sites
41
Air pollution
- smoke and acidic gases released into the atmosphere can pollute the air
- eg. Sulfur dioxide can cause acid rain
42
The process of why human activity today is so bad for the environment
- our increasing population puts pressure on the environment as we take the resources we need to survive
- people around the world today are demanding higher standards of living
- so we use raw materials
- and we also use more energy for the manufacturing processes
- this all means we’re taking more and more resources from the environment more and more quickly
- many raw materials are being used up quicker than they’re being replaced
43
Consequences of global warming
- higher temperatures
- change in distribution of animals and plants
- changes in migration patterns
- biodiversity is reduced
44
Effect of higher temperatures due to global warming
- causes seawater to expand and ice to melt, causing sea level to rise
- it has risen a little bit over the last 100 years
- this is beginning to increase the frequency of flooding in some areas
- if sea levels keep rising it bad for people and animas living in low-lying places and could result in loss of habitat
45
Effect of distribution due to global warming
- distribution is changing as temperature increase and the amount rainfall changes in different areas
- some species are becoming more widely distributed
- for example species that need warmer temperatures are spreading further as the conditions they thrive in exist over a wider area and vice versa
46
Effect of changes in migration patterns due to global warming
- there have been changes in migration patterns
- for example some birds may be migrating further north as more northern areas are getting warmer
47
Effects of global warming on biodiversity
- it could be reduced if some species are becoming more unable to survive a change in the climate
48
Why do humans use land
Building, quarrying, farming, dumping waste
49
Effects of humans using land
- theres less land available for other organisms
50
Why does deforestation happen
- to clear land for farming to provide more food
- to grow crops from which biofuels based on ethanol can be produced
51
3 main problems that deforestation causes
- less carbon dioxide taken in
- more carbon dioxide in the atmosphere
- less biodiversity
52
Less carbon dioxide taken in due to deforestation
- cutting down loads of trees means that the amount of carbon dioxide removed from the atmosphere during photosynthesis is reduced
- tress ‘lock up’ some of the carbon that they absorb during photosynthesis in their wood, which can remove it from the atmosphere for hundreds of years. Removing trees means that less is locked up
53
More carbon dioxide in the atmosphere due to deforestation
- carbon dioxide is released when trees are burnt to clear land (carbon in wood doesn’t contribute to atmospheric pollution until its released by burning)
- microorganisms feeding on its of dead wood release carbon dioxide as a waste product of respiration
54
Less biodiversity due to deforestation
- biodiversity is the variety of different species - the more species, the greater the biodiversity
- habitats like forests can contain a huge number of different species of plants and animals, so wen they are destroyed there is a danger of many species becoming extinct
55
What are peat bogs
- bogs are areas of land that are acidic and waterlogged
- plans that live in bogs don’t fully decay wen they die, because theres not enough oxygen
- the partly rotted plants gradually build up to form peat
- so the carbon in the plants is stored in the peat instead of being released into the atmosphere
56
Why is peat used
- peat bogs are often drained so that the area can be used as farmland or the peat is cut up and dried to use as fuel
- its sold to gardeners as compost
- peat is being used faster than it forms
57
What happens when peat is drained
- it comes into more contact with air and some microorganisms start to decompose it
- when these microorganisms respire, they use oxygen and release carbon dioxide, contributing to global warming
- carbon dioxide is also released when peat is burned as a fuel
58
Effect of destroying bogs
- destroys habitats of some animals, plants and microorganisms that live there, so reduces biodiversity
59
Explain breeding programs to protect ecosystems and biodiversity
- they’ve been set up to help prevent endangered species from becoming extinct
- these are 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
60
Explain programs to protect and regenerate habitats
- Programmes to protect and regenerate rare habitats like mangroves, heathland and coral reefs have been started
- Protecting these habitats helps to protect the species that live there — preserving the ecosystem and biodiversity in the area.
61
Explain programmes to reintroduce hedgerows and field margins
-There are programmes to reintroduce hedgerows and field margins around fields on farms where only a single type of crop is grown.
- Field margins are areas of land around the edges of fields where wild flowers and grasses are left to grow.
- Hedgerows and field margins provide a habitat for a wider variety of organisms than could survive in a single crop habitat.
62
Explain programme to reduce deforestation
- Some governments have introduced regulations and programmes to reduce the level of deforestation taking place and the amount of carbon dioxide being released into the atmosphere by businesses.
- This could reduce the increase of global warming
63
Explain programme to reduce deforestation
- Some governments have introduced regulations and programmes to reduce the level of deforestation taking place and the amount of carbon dioxide being released into the atmosphere by businesses.
- This could reduce the increase of global warming
64
What are people encouraged to do to protect and restore ecosystems
- People are encouraged to recycle to reduce the amount of waste that gets dumped in landfill sites.
- This could reduce the amount of land taken over for landfill, leaving ecosystems in place.
65
Money cost of protecting biodiversity
- Protecting biodiversity costs money.
- For example, governments sometimes pay farmers a subsidy to reintroduce hedgerows and field margins to their land.
- It can also cost money to keep a watch on whether the programmes and regulations designed to maintain biodiversity are being followed.
- There can be conflict between protecting biodiversity and saving money
— money may be prioritised for other things.
66
Cost of livelihood to protect biodiversity
- Protecting biodiversity may come at a cost to local people's livelihood.
- For example, reducing the amount of deforestation is great for biodiversity, but the people who were previously employed in the tree-felling industry could be left unemployed.
- This could affect the local economy if people move away with their family to find work.
67
Conflict between protecting biodiversity and food security
- There can be conflict between protecting biodiversity and protecting our food security.
- Sometimes certain organisms are seen as pests by farmers (e.g. locusts and foxes) and are killed to protect crops and livestock so that more food can be produced.
- As a result, however, the food chain and biodiversity can be affected.
68
Conflict of development and protecting biodiversity
- Development is important, but it can affect the environment.
- Many people want to protect biodiversity in the face of development, but sometimes land is in such high demand that previously untouched land with high biodiversity has to be used for development, e.g. for housing developments on the edge of towns, or for new agricultural land in developing countries.
69
What actually is global warming
1) The temperature of the Earth is a balance between the energy it gets from the Sun and the energy it radiates back out into space.
2)Gases in the atmosphere naturally act like an insulating layer. They absorb most of the energy that would normally be radiated into space, and re-radiate it in all directions (including back towards the Earth). This increases the temperature of the planet.
3) If this didn't happen, then at night there'd be nothing to keep any energy in, and we'd quickly get very cold indeed. But recently we've started to worry that this effect is getting a bit out of hand...
4) There are several different gases in the atmosphere which help keep the energy in. They're called “greenhouse gases", and the main ones whose levels we worry about are carbon dioxide (CO,) and methane — because the levels of these two gases are rising quite sharply.
5) The Earth is gradually heating up because of the increasing levels of greenhouse gases — this is global warming. Global warming is a type of climate change and causes other types of climate change, e.g. changing rainfall patterns.
