Use Of Biological Resources Flashcards
describe how glasshouses and polythene tunnels can be used to increase the yield of certain crops
Easier to keep them free frompests and diseases
Artificial light at night to give more time to photosynthesise
Glasshouses trap the sun’s heat (or use a heater)
Increase conc. of CO2 (eg paraffin heater)
Increased rate of photosynthesis makes plants grow quicker and bigger so yield increases
Describe the use of fertiliser to increase crop yield
Fertilisers ensure crops have enough nutrients eg. Nitrogen, potassium, phosphorus
What are the advantages and disadvantages of using pesticides with crop plants
Advantages: Kill all the pests Act quickly Disadvantages: Poisonous to humans Can harm other wildlife Can kill useful plants Pests may become resistant
What are the advantages and disadvantages of biological control
Advantages: Longer lasting effect than pesticides Less harmful to wildlife Disadvantages: Can become pests themselves Never fully eradicates pest
Explain the methods used to farm fish
maintenance of water quality (temperature, pH, O2 levels are controlled; filtered )
control of intraspecific predation (separate sizes and genders)
Control of interspecific predation ( nets)
control of disease, (pesticides)
removal of waste products, (filtering)
quality and frequency of feeding (pellets)
the use of selective breeding.
What is selective breeding
Mating the best organisms to produce the best offspring
Name three uses for selective breeding
To increase the productivity of cows ( pick the biggest cows over generations)
To increase the number of offspring in sheep
To increase crop yield
What is the role of yeast in the production of beer
Yeast ferments the sugar into alcohol
D escribe a simple experiment to investigate carbon dioxide production by yeast, in different conditions
Mix together sugar, yeast and distilled water and put in a test tube
Attach a bung with a tube leading to second test tube of water
Place in a water bath
Count the number of bubbles for a period of time (eg 3 minutes)
Repeat at different temperatures
understand the role of bacteria (Lactobacillus) in the production of yoghurt
Ferment lactose sugar into lactic acid (which causes milk to clot, making yoghurt)
Explain how a fermenter keeps the right conditions for microorganisms
Liquid culture medium: provides nutrients
pH monitored by pH probe
Temperature monitored and controlled by water jacket and thermometer
Paddles agitate the medium to keep microorganisms in contact with fresh medium
Oxygen pumped in
describe the use of restriction enzymes to cut DNA at specific sites and ligase enzymes to join pieces of DNA together
Restriction enzymes cut out the DNA you want to insert
Same restriction enzyme cuts out the vector DNA
Ligase joins together the two pieces of DNA to produce recombinant DNA
Recombinant DNA inserted into other cells
What does transgenic mean
transfer of genetic material from one species to a different species
What is a vector
Used to transfer DNA into a cell
1) plasmid
2) viruses
Describe the process of micro propagation
A plant with desired characteristics is chosen
Explants are taken from tips of stem and side shoots
Explants are sterilised
Explants grown in vitro (Petri dish with nutrient medium)
Growth hormones
Cells in explants divide and grow into small plant
These plants are genetically identical to the first one
