Ecology Flashcards
What is a community?
All the populations of different species that live together in a habitat
What is an ecosystem?
the interaction of a community of living organisms (biotic) with the non-living (abiotic) parts of their environment.
What are 4 things animals compete for?
food
water
mates
territory
What are 4 resources plants compete for?
water
mineral ions
light
space
What are 3 biotic factors?
disease
availability of food
predators
What are 4 abiotic factors?
mineral ions in soil
soil pH
wind intensity
temperature
light intensity
What does the term ‘structural adaptations’ refer to?
The physical features of the organism
What are 2 examples of structural adaptations?
the shape of an organism
the colour of an organism
What does the term ‘behavioural adaptations’ refer to?
the way an organism acts
What is an example of a behavioural adaptation?
The response of an organism when it sees a predator
What does the term ‘functional adaptations’ refer to?
The processes that take place within an organism
What is an example of functional adaptation?
How an organism metabolises chemicals
Some species of bird migrate to different regions of the world at certain times of the year.
Which type of adaptation is this?
bahavioural
Some species of snake have bright and distinct patterns on their scales to warn other species that they are venomous.
Which type of adaptation is this?
structural
What is an extremophile?
Extremophiles are microorganisms that live in extreme environments, such as those with high temperatures, pressures, or salt concentrations.
What type of organisms are extremophiles?
bacteria and archaea
What is a food chain?
A model that shows how energy passes from organism to organism
What are Organisms at the very start of a food chain that can create glucose using photosynthesis known as?
producers
What are 2 producers?
algae
plants
What do primary consumers feed on?
Producers
What do tertiary consumers eat?
secondary consumers
What are quadrats used for?
to measure abundance
What are transects used for?
to measure how distribution changes
Describe how you might use a 1m x 1m quadrat to estimate the number of dandelions in a 100m x 100m field.
1Place multiple tape measures along the length and width of the field, forming a large grid.
2Use a random number generator to generate 10 pairs of random coordinates.
3Place quadrats at those coordinates and count how many dandelions are found in each quadrat.
4Calculate the mean number of dandelions per m2.
5Estimate the total population size using our mean number of dandelions per m2 and the total area of the field.
What are usually the dimensions of a quadrat?
1m x 1m
What is a transect?
A line through a habitat along which organisms are sampled
Which three processes in the carbon cycle release carbon dioxide into the atmosphere?
Decomposition
Combustion
Respiration
What 2 groups of organisms carry out discomposition?
detritivores and decomposers
What are detritivores?
small animals like worms and woodlice that feed on dead organic matter
What are decomposers?
microorganisms like bacteria and fungi
What are 3 factors that effect the rate of decomposition?
oxygen availability
temperature
water
Why could the rate of decomposition fall if soil becomes waterlogged?
(Water fills the air gaps within the soil, so there will be) less oxygen
Less aerobic respiration
Fewer chemical reactions and thus slower decomposition
What is compost made of?
dead plants
What is anaerobic decay?
Some decomposing microorganisms can break down organic material without oxygen. In these cases, the microorganisms carry out anaerobic respiration and so it is called ‘anaerobic decay’.
What is the mixture of gases anaerobic decay produces called?
biogas
What is the most important biogas?
methane
What are biogas generators?
large containers in which animal or plant waste is left to decay anaerobically.
What useful things do biogas generators produce?
biogas (methane)
Once the biogas is removed from the tank, a sludgy material is left over, which contains a high density of useful minerals. This can be spread on fields like fertiliser.
Give three reasons why maintaining high biodiversity is important.
It increases the stability of the ecosystem, so that changes are less likely to have adverse affects
Many species provide specific services, such as pollination
Many of our medicinal drugs come from wild species
What are 2 impacts of rapid human growth?
More resources are being used
More waste is being produced
What 2 substances contribute the most to water pollution?
fertiliser from agriculture
sewage from cities
What 2 substances contribute the most to air pollution?
Acidic gases from burning fossil fuels
Smoke from combustion
What 2 substances contribute the most to land pollution?
nuclear waste
landfill
Which sort of species do breeding programs seek to help?
those that face extinction
How do field margins and hedgerows in agriculture help increase biodiversity?
They provide extra habitats and food sources so that a wider range of species can survive.
What are 3 greenhouse gases?
methane
carbon dioxide
water vapour
Give three reasons for deforestation.
To clear land for agriculture
Logging for wood
Mining
What is the soil of peat bogs like?
waterlogged
acidic
Do peat bogs have high or low levels of oxygen?
low
Which two human activities contribute to peat bog destruction?
Draining the peat to use the land for agriculture
Cutting out the peat to burn as a fuel
What is peat?
build up of partially rotted plants that form peat
Why is peat good?
it holds all the carbon dioxide from the dead plants
Explain how draining peat bogs contributes to global warming.
The draining of water allows air (and oxygen) to return to the soil
This allows microorganism to carry out aerobic respiration and decay the organic matter
This releases CO2 which acts as a greenhouse gas, and contributes to global warming
Which trophic level contains secondary consumers?
Trophic level 3
Why are food chains usually no longer than five or six trophic levels?
Only ~10% of the energy and biomass is transferred between each level
Roughly what proportion of energy biomass is transferred between trophic levels?
10%
Give three reasons why only ~10% of the energy & biomass is passed on at each stage in a food chain?
not everything may be eaten
some material eaten may not be absorbed
most the energy that is absorbed is used for movement and faeces etc.
How do sustainable fisheries contribute to the maintenance of fish stocks?
By implementing fishing quotas for responsible harvesting
What is the purpose of increasing the size of fishing nets?
To allow young fish to escape
What is the purpose of fishing quotas?
To maintain balanced ecosystems
What are the 2 key features of food security?
Sustainable for the planet into the future
Access enough safe and nutritious food to meet their requirements for a healthy life
How could the spread of pathogens across the world affect food security?
they could damage/kill plants which would decrease their yield so there would be less food available
Give 2 ways in which changing diets could negatively affect food security.
Increased consumption of resource intense foods such as meat
Increased consumption of foods that have to be transported long distances across the world
Give 3 factors that could negatively affect food security.
Rising populations
Changing diets
Pests and pathogens
Environmental change (higher temperatures, droughts, floods, changing rainfall etc)
More expensive agricultural inputs (like fuels, pesticides, fertilisers etc)
Conflicts/wars
What is food security?
all people are able to access enough safe and nutritious food to meet their requirements for a healthy life, in ways the planet can sustain into the future.
Over the past 200 years, why has the food that we eat become more intensive to produce?
Our diets have changed to include food that require more land and resources to produce.
For example we consume more meat and fewer grains.
