Echology And The Environment Flashcards
What does a food chain show us?
Which organisms eat others organisms, whilst also showing the transfer of energy from one organism to the next
What does a producer do?
Starts the food chain, produces own food by photosynthethis
What is a primary consumer?
Herbivore, feeds of prey
What is a secondary consumer?
Carnivore, prey, predator
What is a tertiary consumer?
Carnivore, predator
What is a tropic level?
Stage in the food chain (eg. Producer)
What is meant by the term population?
Number of 1 species
What do pyramids of number show us?
The number of organisms in each tropic level of a food chain
What do ecological pyramids start with?
The producer on the bottom bar
What does a pyramid of biomass show us?
The total mass of biological (living) material of the organisms in each trophic level
What is biomass lost as and how is it released?
It’s lost as energy in respiration as heat to the surroundings
Why is biomass lost?
Some of the food is not eaten (roots, bones etc)
What form is biomass realised in?
Urine and faeces (excretion, egestion)
How do biotic factors and abiotic factors influence an ecosystem?
They influence the numbers and distribution of organisms in an ecosystem
What are some examples of things biotic?
Amount of prey, disease, preditation, amount of mates
What are some examples of things abiotic?
Rainfall, temperature, oxygen content, soil condition
What is sampling?
A way of taking measurements from a small area which are representative of a larger area
How do you make estimates for a larger area when sampling?
Scale up the sample
What is used to take a sample of plants or animals?
A quadrat (square frame enclosing on a known area)
Where is carbon found?
In all main biological molecules
What makes up lipids?
Fatty acids and glycerol
What forms proteins?
Amino acids by joining together
What joins to make carbohydrates?
Monosaccharides (sugars)
What are examples of all main biological molecules?
Lipids, proteins, carbohydrates, DNA
What is the carbon cycle?
The cycling of carbon between environment and organisms
What are the key processes involved in the carbon cycle?
Photosynthesis and respiration
What does decomposition in the carbon cycle consist of?
Microorganisms called decompressors that digest waste and dead organisms
What microorganisms are used in decomposition?
Bacteria and fungi
What do carbon compounds in dead waste material turn into?
Carbon dioxide in the air
What is the meaning of the term community?
A group of different populations of organisms that live in the same habitat
What does the term habitat mean?
The place where organism lives
What is an ecosystem?
A community of animals, plants, micro-organisms or non-living things and their shared environment
Why is only about 10% of energy transferred from one trophic level to the next?
Most of the energy is lost as heat to the environment
What effect is the increase of human population having on the environment?
Reducing biodiversity (no. of different species in an area) and increasing air and water pollution
What are the greenhouse gases?
CO2, methane, Nitrogen oxide, CFC’s, Water vapour
What will an increase in greenhouse gases cause?
More global warming
How does the surface of the earth heat up therefore causing global warming?
Greenhouse gases are trapped in the atmosphere reflecting radiation back to the earth
What are the physical effects of global warming on the planet?
Melting of polar ice caps —> rise in sea levels, changes in rainfall —> flooding/drought, extinction of species
What can burning fossil fuels create?
Sulfur dioxide and nitrogen oxide which dissolve in rainwater to form acid rain
What effect will acid rain have on planet life?
Damages leaves leading to less photosynthesis and a change of PH in the soil affecting growth
What effect does acid rain have on aquatic life
Acidification of water damaging aquatic animals and plants
What concentration is nitrate found in?
Low
What are nitrates important for?
Building amino acids and protein for growth
What happens to plants with low availability of nitrates?
Stunted growth
Why do farmers add fertilisers to crops?
Nitrates in them improve the soil fertility
What happens to excess artificial fertilisers?
They’re washed out of the soil by rain (leaching) and run into rivers, streams and lakes
What can leaching lead to?
Eutrophication
What is the first stage of eutrophication?
Inorganic fertilisers used of fields are leached into nearby rivers, lakes and streams
What is the second stage of eutrophication?
Increased concentration of mineral ions stimulates growth of aquatic plants, rapid growth of algae on surface of water (algal bloom)
What is the third stage of eutrophication?
Increased growth causes overcrowding for many plants, algal bloom blocks light from plants at bottom of water and prevents photosynthesis
What is the fourth stage of eutrophication?
Many of the plants die and aerobic bacteria decomposes the plant material, using up the oxygen in the water
What is the fith stage of eutrophication?
Low oxygen content, fish and other organisms die, water becomes anoxic (only anaerobic organisms survive)
