Use Of Biological Resources Flashcards
How are Fertilisers used to increase Crop Yield?
- Plants need nitrogen, potassium, phosphorus to make compounds (proteins)
- If dont get enough minerals - growth and life affected
- Fertilisers used to replace missing minerals or provide more of them
- Increase crop yield
How can a Greenhouse create ideal conditions for Photosynthesis?
- Plants enclosed - prevent pests and diseases
- Artificial light - more photosynthesis
- Paraffin heater - increase level of CO2
- Trap suns heat/heater - warm plants
- Plants grow bigger and faster - crop yield higher
What are types of Pest Control?
- Pesticides - May harm wildlife
* Biological Control - use other organisms to reduce number of pests - less harmful
What is Fermentation?
- Microorganisms break down sugars to release energy
* Usually by Anaerobic Respiration
How is Yoghurt made?
- Milk pasteurised (heated) to kill bacteria
- Milk is cooled
- Lactobacillus bacteria added, mixture is incubated (40 degrees) in a fermenter
- The bacteria ferment the lactose sugar in milk to form lactic acid
- Lactic acid causes milk to clot and solidify into yoghurt
What are Fermentors used for?
- Get a higher yield
- Make more products commercially viable
- Easy to sterilise
What does the Cooling Jacket on a Fermentor do?
Removes heat energy, stopping fermentor overheating and enzymes denaturing
What does the Stirrer for Mixing on a Fermentor do?
- Keep both well stirred to oxygenate all parts of fermentor
* Prevent microorganisms setting
What does the Air Filter on a Fermentor do?
Filters air coming in, maintaining sterile conditions
How do you make bread?
- Dough - yeast, flour, water, sugar
- Left in warm place to rise
- Enzymes break down carbohydrates in flour into sugars
- Yeast uses sugars in aerobic respiration, producing carbon dioxide
- When O2 run out = anaerobic respiration - fermentation, produce CO2 + ethanol
- CO2 trapped in bubbles in dough
- Dough roses
- Baked, temp of dough rises enough = kill yeast and alcohol = bread stoped rising
How do you make beer?
- Barley seeds germinated, make amylase to digest starch
- Seeds killed/dried to make malt
- Malt mixed with water in a mash tun, amylase break down starch to maltose
- Mash boiled and filtered
- Hops add for taste, yeast to ferment sugars, making beer
- Beer centrifuged, filtered, pasteurised
- Beer put in barrels
Why are Organisms selectively bred?
- To get maximum yield : milk
- Good health + disease resistance
- Qualities : Speed, fertility, temperament, good mothering skills
- Plants : attractive flowers, nice smell
What is the process of Selective Breeding?
- From stock, select ones with best characteristics
- Breed then with each other
- Select best of offspring, breed them together
- Continue process over generations, desirable trait gets stronger
- Better yield
Define Selective Breeding:
- Choosing animals or plants with desired characteristics for breeding
- Usually carried on for many generations
How can Selective Breeding Increase Crop Yield?
- Combine 2 different desirable characteristics
- Tall wheat plants = high grain yield, easily damaged by wind/rain
- Dwarf wheat plants = low grain yield, resist wind/rain
- Plants cross bred, combine good characteristics
- Dwarf wheat plants can now resist bad weather and have a high grain yield
