Separate Biology - B7 Ecology Flashcards
What is an ecosystem?
The interaction of a community of living organisms (biotic) with the non-living (abiotic) parts of the environment
What four things do plants compete for?
- Light
- Space
- Water
- Mineral ions
What is a community?
A group of animals and/or plants of different species
What are extremophiles? Give examples of conditions they might live in.
Organisms which live in extreme environments
e.g. high temperature, pressure or salt concentration
What is a population?
A group of animals or plants of the same species
What three things do animals compete for?
- Food
- Mates
- Territory/space
List three biotic factors which can affect a community.
Any three from:
- Availability of food
- New predators arriving
- New pathogens
- One species outcompeting another (so numbers are no longer sufficient to breed)
List three abiotic factors which can affect a community.
Any three from:
- Light intensity
- Temperature
- Moisture levels
- Soil pH and mineral content
- Wind intensity and direction
- CO2 levels for plants
- O2 levels of aquatic animals
Give two examples of producers
Plants and algae
What gases are contributing to global warming?
- Carbon dioxide
- Methane
- Water Vapour
Name three processes in the carbon cycle
Any three from:
- Photosynthesis
- Respiration
- Decay
- Burning/combustion
- Carbon locked up in fossil fuels
- Animals eating plants and other animals
What are the reasons for people doing deforestation?
- To provide land for cattle and rice fields
- Growing crops for biofuels
Give two examples of factors that reduce biodiversity.
- Deforestation
- Global warming
Give three things that are in place to reduce the negative impact on biodiversity?
Any three from:
- Breeding programmes for endangered species
- Protection / regeneration of rare habitats
- Reintroduction of field margins
- Reduction of deforestation and CO2 emissions
- Recycling resources
What are the four main stages in the water cycle?
- Evaporation
- Condensation
- Precipitation
- Transpiration
What is biodiversity?
The variety of all the different species of organisms on Earth.
What environmental problem does sulfur dioxide cause?
Acid rain
What environmental problem does soot/solid particulates cause?
Global dimming
Give an example of interdependence in a community.
Examples include:
Species depending on each other for:
- Food
- Shelter
- Pollination
- Seed dispersal
What are the three different types of adaptations?
- Structural
- Behavioural
- Functional
Give three ways humans have used land and, as a result, reduced biodiversity?
Any three from:
- Quarrying for metals
- Building
- Farming
- Deforestation
- Landfill sites
What environmental problem does carbon dioxide cause?
Global Warming
What is a stable community?
Population size remains fairly constant
(because the species and environmental factors are in balance)
Name the primary consumer in the food chain below:
Grass -> Rabbit -> Fox -> Eagle
Rabbit
Name the organisms that are responsible for decay.
Microorganisms
What are the two major impacts of a rapidly increasing human population?
- More resources used
- More waste produced
How does the destruction of peat bogs affect biodiversity?
Reduces biodiversity (because it removes habitat for the species that live there)
Peat can be used as a fuel. How does this impact the environment?
- Peat is burned
- Carbon dioxide is released
- Carbon dioxide causes global warming
How does decay contribute to global warming?
- Microorganisms are involved in decay.
- Microorganisms respire and release carbon dioxide
What are the three main categories of pollution?
- Water (sewage, fertilisers or toxic chemicals)
- Air (smoke and acidic gases)
- Land (landfill and toxic chemicals)
Explain how the destruction of peat bogs contributes to global warming.
- Peat is dug and removed or water is drained from the peat bog.
- Oxygen enters the peat bog.
- Microorganisms decay the plant material in the peat bog.
- Microorganisms respire and release carbon dioxide.
Name the secondary consumer in the food chain below:
Grass -> Rabbit -> Fox -> Eagle
Fox
Name the tertiary consumer in the food chain below:
Grass -> Rabbit -> Fox -> Eagle
Eagle
What do the arrows in the food chain represent?
Grass -> Rabbit -> Fox -> Eagle
The transfer of energy
Name the grid used to randomly sample organisms.

Quadrat
Name the sampling technique shown in the image.

Transect
Name the producer in the food chain below:
Grass -> Rabbit -> Fox -> Eagle
Grass
What are predators?
Consumers that hunt and kill other animals
What are prey?
Animals eaten by predators
Give three consequences of global warming.
Examples include:
- Change in species distribution
- Changes in rainfall patterns
- Flooding
- Droughts
- Sea level rise
- More frequent extreme weather events
What is a bog?
An area of land that is acidic and waterlogged
Separate Q. What are the three things that make the optimum conditions for decay?
- Warm
- Moist
- Good oxygen supply
Separate Q. What gas is produced in anaerobic decay?
Methane gas
Separate Q. Describe the required practical to investigate the effect of temperature on the rate of decay of milk by measuring pH change.
- In one test tube, add 5 cm3 of lipase solution.
- In a second test tube, add 5 cm3 of milk, a few drops of phenolphthalein and 7 cm3 of sodium carbonate. This will turn pink because the mixture is alkaline.
- Put both test tubes in a water bath at 30 oC.
- Remove 1 cm3 of the lipase solution. Add this to the 2nd test tube containing milk & start a timer.
- Record the time it takes to lose its pink colour.
- Repeat this for a range of temperatures (10 oC, 20 oC, 40 oC & 50 oC). Repeat each temperature 3x and calculate a mean.
- Calculate rate of decay for each temperature using the equation: Rate = 1000/time
Separate Q. What two products are produced when waste material is fed into a biogas generator?
- Digested material (to be used as a fertiliser)
- Biogas (methane – to be used as a fuel)
Separate Q. What is compost used for?
As a natural fertiliser for growing garden plants or crops.
Separate Q. What is the methane produced in biogas generators used for?
Fuel
Separate Higher Q. What three main environmental changes can affect the distribution of a species in an ecosystem?
- Temperature
- Availability of water
- Composition of atmospheric gases
Separate Q. In what tropic level are the producers found?
Trophic Level 1
Separate Q. In what trophic level are herbivores found?
Trophic Level 2
Separate Q. Describe how decomposers break down dead animal and plant matter
- Decomposers (e.g. microorganisms) secrete enzymes into the environment.
- The enzymes break down large molecules into smaller ones.
- The small soluble molecules then diffuse back into the decomposer.
Separate Q. What percentage of the incident energy from light is transferred for photosynthesis by producers?
About 1%
Separate Q. What equation is used to calculate the efficiency of biomass transfer between trophic levels?

Separate Q. What is an apex predator?
Carnivore at the end of the food chain with no predators
Separate Q. Why does not all of the biomass get passed up to the next trophic level? Give three reasons.
- Not all ingested material is absorbed into the body, some is lost as faeces.
- Some of the absorbed material is lost when the animal respires (e.g. as carbon dioxide and oxygen)
- Waste products of water and urea are lost in urine.
Separate Q. What percentage of biomass from each trophic level is transferred to the level above?
About 10%
Separate Q. What is food security?
Having enough food to feed a population
Separate Q. What six biological factors are threatening food security?
- Increasing birth rate
- Changing diets
- New pests and pathogens
- Environmental changes (e.g. famine in drought)
- Cost of agricultural inputs
- Conflicts
Separate Q. Why are some farmed animals fed a high protein diet?
To increase the growth of the animals
Separate Q. Give two controls put into place for fisherman so that fish stocks are maintained.
- Control of net size
- Fishing quotas
Separate Q. Label the trophic levels on the pyramid of biomass.


Separate Q. Give two ways by which the efficiency of food production be improved.
Restricting the energy transfer from food animals to the environment by:
- Limit their movement
- Control temperature of enclosures
Separate Q. What is happening to fish stocks in the ocean?
They are declining
Separate Q. Give two solutions we could use to meet the food demands of a growing population.
- Create more food using biotechnology
- Grow more GM crops
Separate Q. What is Fusarium?
A fungus useful for producing mycoprotein (a protein-rich food suitable for vegetarians)
Separate Q. How is mycoprotein produced?
- Fusarium fungus is grown on glucose syrup in aerobic conditions.
- The biomass is harvested and purified.
Separate Q. What is golden rice?
- A GM crop which could provide food with improved nutritional value.
- Golden Rice has been genetically engineered to produce a chemical that’s converted to Vitamin A in the body.
Separate Q. Describe how bacteria are genetically modified to produce insulin.
- The gene for insulin production is cut from human DNA using restriction enzymes (leaving sticky ends).
- The same restriction enzymes cut open a bacterial plasmid (leaving the same sticky ends).
- The ligase enzyme is used to join the sticky ends of the insulin gene to the sticky ends of the plasmid.
- Tis recombinant DNA is inserted into a bacterium.
- The bacteria multiply rapidly and the insulin is harvested and purified.