Ecology (2) Flashcards
What resources do plants compete for? (4)
What resources do animals compete for? (4)
Plants- space, light, water, nutrients
Animals- space, food, water, mates
Biotic factors-
Abiotic factors-
Biotic factors- new predators, competition, new pathogens, food availability
Abiotic factors- moisture, light, temperature, CO2, wind, Oxygen, Soil PH and mineral content
What is an adaptation?
Structural-
Behavioural-
Functional-
A change that makes an organism better-suited to its environment
Structural- changes in body structure (eg fur colour)
Behavioural- changes in behaviour (eg migration patterns)
Functional- changes to bodily functions to better survive (desert animals conserving water)
Using quadrats RP
- Choose a sample area in a field or school ground.
- Use a random method (e.g., random number generator or coordinates) to place the quadrat.
- Count the number of a specific organism (e.g., daisies) within the quadrat.
- Repeat the process multiple times for reliability.
- Calculate the mean number of organisms per quadrat.
- Multiply by the total area of the field to estimate the total population.
Transects RP
- Lay a tape measure across a changing habitat (e.g., from a tree to open ground).
- Place quadrats at regular intervals along the transect.
- Record the number of organisms in each quadrat.
- Repeat to improve reliability.
- Analyse how species distribution changes along the transect as a result of factors (eg measure light intensity with a lux meter)
Water cycle
Evaporation – The sun heats water from oceans, lakes, and rivers, turning it into water vapour.
Transpiration – Water evaporates from plant leaves (mainly through stomata), adding water vapour to the atmosphere.
Condensation – Water vapour cools and forms clouds as it turns back into liquid droplets.
Precipitation – Water falls from clouds as rain, snow, sleet, or hail.
Percolation & Infiltration – Water soaks into the soil and moves through rocks, replenishing underground water stores (aquifers).
Surface Runoff – Water flows over the land into rivers, lakes, and oceans.
Collection – Water gathers in bodies of water, completing the cycle.
carbon cycle
Photosynthesis – Plants absorb carbon dioxide (CO₂) from the atmosphere and use sunlight to convert it into glucose (C₆H₁₂O₆) and oxygen.
Respiration – Organisms (plants, animals, microorganisms) release carbon dioxide back into the atmosphere by breaking down glucose to release energy.
Decomposition – Dead plants and animals are broken down by decomposers (bacteria, fungi), releasing carbon back into the soil or atmosphere as CO₂.
Fossilisation – Over millions of years, carbon from dead organisms can form fossil fuels (coal, oil, natural gas), which store carbon.
Combustion – The burning of fossil fuels or organic matter releases carbon dioxide into the atmosphere.
Carbon Sequestration – Some carbon is stored in the oceans and soil, in the form of dissolved CO₂ or organic material.
decay
Decomposition – The breakdown of dead organisms or waste material by decomposers (bacteria, fungi, invertebrates).
Role of Decomposers –
Bacteria and fungi break down dead material into simpler substances.
They feed on dead organisms, using enzymes to digest them externally before absorbing the nutrients.
Some decomposers break down proteins into amino acids and release nitrogen compounds into the soil.
Release of Nutrients – During decay, carbon (as CO₂) and nitrogen compounds (like ammonia) are released back into the soil and atmosphere, making them available for plants to use.
factors affecting rate of decay (4)
Factors Affecting Decay –
Temperature: Warmer temperatures speed up enzyme activity, increasing decay rate.
Oxygen: Most decomposers need oxygen for respiration, so decay is faster in aerobic conditions.
Moisture: Decomposers need water to survive, so damp conditions promote faster decay.
Surface Area: The larger the surface area of the material being decayed, the faster it breaks down (e.g., smaller pieces decay faster).
Biogas generators
organic matter anaerobically decomposes to release methane, which is a highly flammable gas used for cooking/heating etc
Investigating decay RP (milk)
- measure 5cm3 of lipase and milk into separate test tubes
- add some phenolphaline indicator into the milk
- add 7cm3 of sodium carbonate into the milk tube
- leave both tubes in a water bath set at 30*c
- add 1cm3 of lipase into the milk using a pipette and start a stopwatch
- stir with a glass rod
- when the solution is no longer pink, stop the stopwatch
- repeat at different temperatures
- use rate = 1000/time
What is biodiversity
variety of organisms in an ecossytem
What are the trophic levels in an ecosystem
How much energy is lost at each stage and why
Trophic levels refer to the different stages in a food chain, representing the flow of energy and nutrients through an ecosystem
Producers, primary consumers, secondary consumers, tertiary consumers
Decomposers break down uneaten remains and waste
Energy is passed from one trophic level to the next, but only about 10% of the energy is transferred to the next level. The rest is lost as heat, used for metabolism, or excreted as waste.
Pyramids of biomass
equation for biomass efficiency
the bar representing energy at the bottom from producers is greater than the bar above for primary consumers as not all energy is transferred
The bar decreases with each trophic level
efficiency = biomass transferred to next level / biomass available from previous level X 100
Biotechnology:
Mycoproteins-
Insulin-producing bacteria-
GM crops-
Mycoprotein- A protein-rich food made from fungi (usually Fusarium) grown on glucose.
Used as a meat substitute in vegetarian and vegan diets.
Insulin-Producing Bacteria- Bacteria are genetically engineered to produce human insulin.
The gene for insulin is inserted into the bacteria’s DNA.
Used to treat diabetes by providing a reliable, large-scale supply of insulin.
GM Crops- Crops that have been genetically modified to include desirable traits (e.g., pest resistance, drought tolerance).
Can increase crop yields and reduce the need for chemical pesticides.
How can Food security be increased (3)
fishing quotas and net sizes
indoor reared livestock
