What is Exponential growth | Nothing limiting a populations size |
What are fertilisers used for | Adds extra nitrates to the soil to increase and speed up plant growth |
What are pesticides used for | To kill pests that destory/ eat crops |
Describe the use of nitrates in a plant | To make amino acids (Nitrates → amino acids → proteins) |
Describe the stages of Algal Bloom | 1- Fertilizer leach into water adding unwanted nitrates
2- Increase Algal populations which reduces sunlight from getting to aquatic plants
3- The plants die then becoming food for bacteria
4- The bacteria take up lots of oxygen reducing oxygen availability for living organisms like fish so they die |
What don't dissolve into water easily so less algal blooms are formed | Manure and Compost |
Why do you have to be careful when using pesticides | They can accumulate in the crop and can be eaten by consumers |
What is Biological control | The use of living organisms instead of chemicals to kill pests |
How can Genetically modified crops help | Crops can be genetically modified to become resistant to pests |
What is Bioaccumulation | Pesticides sprayed onto crops can gatherin the bodies of organisms over time, as they are passed along the food chain, toxicity increases and can reach lethal levels |