Ecology (seneca) Flashcards
An ecosystem is made up of …
living (biotic) and non-living (abiotic) parts. In an ecosystem, there are different levels of organisation.
———- are the smallest part of an ecosystem.
Individual organisms
Populations of individual organisms make up a …
single species.
An ecosystem is made up of living organisms (——) and non-living (abiotic) parts.
biotic
An ecosystem is made up of living organisms (biotic) and non-living (———) parts.
abiotic
Animals often compete for …
food, mates and territory.
Plants often compete for…
water and mineral ions (minerals) from the soil, as well as for light and space.
what are populations?
Groups of individual organisms that make up single species
what are Individuals?
The smallest part of an ecosystem
what are Communities?
These are made up of populations of different species
There is interdependence between different species. This means that one species may rely on another species for different things, such as:
- A species may depend on another for food.
- A species may depend on another to spread its seeds.
- A species may depend on another for pollination (transfer of pollen).
- A species may depend on another for shelter.
A community is stable when:
- species are balanced
- the environment is balanced
- population numbers are constant
When a community is stable, the populations within it are:
fairly constant
Food chains show the …
feeding relationships within a community
Food chains nearly always begin with a …
producer that makes its own food.
Producers are eaten by …
animals called primary consumers.
Primary consumers are eaten by …
secondary consumers.
Secondary consumers are eaten by …
tertiary consumers.
An apex predator is …
at the top of the food chain.
Predator-prey graphs show the …
cyclical nature of predator and prey populations in stable communities.
Environmental change affects the …
distribution (spread) of species, and in extreme cases, their longevity (how long they survive).
Polar bears hunt seals on floating sea ice.
Increasing temperatures cause …
this ice to melt. This means that the polar bears are no longer able to hunt their main food source.
Carbon dioxide dissolves in water and increases …
the water acidity.
Carbon dioxide dissolves in water and increases the water acidity.
Acidic water hinders …
corals’ ability to build a skeleton. This means that the increased carbon dioxide in the atmosphere prevents coral growth.
Wildebeests migrate annually from the …
Serengeti plains of Tanzania Northwards into Kenya to track seasonal changes in rainfall patterns.
Environmental changes can come about for many different reasons, including:
- Geological activity
- Seasons
- Humans
give examples of geological activity:
- Volcanic eruptions change the composition of atmospheric gases.
_ Storms and droughts change the availability of water.
give examples of Seasons activity:
- Many countries have rainy and dry seasons.
- The difference in temperature between winter and summer drives birds on worldwide migrations.
give examples of Humans activity:
- Through the burning of fossil fuels, humans increase the atmospheric concentration of greenhouse gases.
- People can change water availability through the building of large dams. The pollution of water sources can make them toxic to wildlife.
Environmental changes affect …
species, their distribution and, in extreme cases, their longevity.
Volcanic eruptions change the …
composition of atmospheric gases.
Many countries have rainy and dry seasons.
The difference in temperature between winter and summer drives …
birds on worldwide migrations.
Examples of Environmental Changes That Affect Species:
- water
- atmospheric gases
- temperature
People can change ——- availability through the building of large dams, and pollution of water sources can make them toxic to wildlife.
water
People can change water availability through the …
building of large dams, and pollution of water sources can make them toxic to wildlife.
Experimental tools for looking at ecosystems and their populations include:
- Transects
- Quadrats
Quadrats are …
square frames that can be used to estimate population sizes.
Transects can be used to …
investigate the effect of a factor on the distribution of a species.
A transect line is a …
piece of tape that is stretched across the habitat of interest.
Quadrats are placed at …
regular intervals along the transect line.
The median is the…
middle value in a numerically ordered series.
The mode is the …
most common value in a series.
population =
number counted x (total survey area / area sampled)
Area of n quadrats =
number of quadrats × length of quadrat × width of quadrat
The recycling (using again) of materials is essential as they …
provide the building blocks for future organisms.
The recycling (using again) of materials is essential as they provide the building blocks for future organisms. Two cycles that are particularly important for living organisms are:
- The carbon cycle
- The water cycle
———- is present in all living organisms.
Carbon
When organisms die, the carbon is recycled so that it can be …
used by future generations.
describe the carbon cycle:
Carbon is present in all living organisms.
When organisms die, the carbon is recycled so that it can be used by future generations.
The water cycle describes how …
water moves on, above or just below the surface of our planet between different locations, such as rivers, oceans and the atmosphere.
In order for the water cycle to be completed, water has to …
change state.
When animals and plants die, decomposers return the …
carbon locked in their bodies back to the atmosphere via decay.
——- of fossil fuels is another source of carbon entry into the atmosphere.
Combustion
When water vapour cools and condenses in the atmosphere, what two forms can it take?
- rain
- snow
Water evaporates from the Earth’s surface, before rising up into the atmosphere. Once in the atmosphere, the water vapour …
cools and condenses into either rain or snow, which eventually returns to the Earth’s surface.
Biological material in the form of —————— decays as a result of the activity of decomposers.
waste products or dead organisms
The rate of the decay process is dependent on:
- Moisture availability
- Oxygen availability
- Temperature
For the decay process, ——- moisture availability is usually best.
High
For the decay process, ———oxygen availability is usually best.
High
For the decay process, —— temperature is usually best.
High
Anaerobic decay happens when the …
oxygen supply is insufficient (not enough), and results in the production of biogas, which is mainly methane.
Biogas generators produce —————– . It can also be used to produce slurry which can also be used as a fertiliser.
methane gas, which is used as a fuel
Biogas generators produce methane gas, which is used as a fuel. It can also be used to produce…
slurry which can also be used as a fertiliser.
Biogas generators produce methane gas, which is used as a fuel. It can also be used to produce slurry which can also be used as a fertiliser.
It is crucial that…
temperatures are maintained at a suitable level and that oxygen is not allowed to enter the site of fermentation.
Can you suggest potential ways to make sure that the temperatures in biogas generators stay at a suitable level?
- Bury the generators underground.
- Cover them in insulating jackets.
Which gas do biogas generators produce that can be used as a fuel or slurry?
methane
Biogas generators are devices that can produce methane gas as a fuel for purposes such as …
cooking, heating or refrigeration
Biogas generators are devices that can produce methane gas as a fuel for purposes such as cooking, heating or refrigeration. The inputs depend on the …
scale of the generator
Large-scale generators take …
waste from sugar factories or sewage works.
Small-scale generators are used by …
households and farms.
Small-scale generators are used by households and farms.
Typical inputs include …
egested (excreted) material from humans and animals, as well as farm and garden waste.
Investigate the effect of temperature on the rate of ————– by measuring pH change.
decay of fresh milk
Investigate the effect of temperature on the rate of decay of fresh milk by measuring …
pH change.
The effect of —————- on the rate of decay can be observed using milk.
temperature
As milk takes a long time to decay, lipase and sodium carbonate are added to …
speed up the decay.
As milk takes a long time to decay, ———————– carbonate are added to speed up the decay.
lipase and sodium
As milk decays, its pH ————-. This can be observed with an indicator called Cresol red.
reduces
As milk decays, its pH reduces. This can be observed with an indicator called …
Cresol red.