Use of biological resources Flashcards
Why do greenhouses increase crop yield?
Keeps disease and pests away Artificial light Keeps plants warm Control Co2 concentration More Photosynthesis=bigger yield
What are fertilisers used for?
So plants have enough nutrients
What are pesticides used for?
Killing pests to stop them eating plants
Are toxic so only little used
What’s biological control?
Introducing a predator to kill of pests
Long lasting but can cause other problems
What’s fermentation?
Microorganisms break down sugars to release energy by anaerobic respiration
How’s yoghurt made?
Equipment sterilised
Milk is pasteurised and cooled
Lactobacillus bacteria is added, it’s incubated in a fermenter
Bacteria ferment lactic sugar, creating lactic acid
Flavours are added then it’s packaged
What do fermenters do?
Allows microorganisms to reproduce and grow in best conditions giving the best yield
How to fermenters get the best yield?
Lots of nutrients in medium Optimum ph Optimum temperature Paddles move culture around Optimum oxygen concentration Unwanted microorganisms sterilised and killed
How’s yeast turned into beer?
Barley grains undergo malting malted grain is mashed up with water Hops added to give flavour Yeast ferments solution Yeast killed off due to alcohol Pasteurised and served
How to measure the respiration rate of yeast in different temperatures?
See how much Co2 produced using the water bath method
What’s selective breeding?
Mating the best organisms to get the best offspring
Why is selective breeding done in animals?
Better milk production
More reproductive
Combing good characteristics
Benefits of fish farming in cages?
Protects fish from predator
Given a controlled diet
They can be selectively bred
Negatives of fish farming in cages?
Fish are prone to disease and parasites
To stop this pesticides are used which cause polloution
Why are fish farmed in tanks?
Ph and oxygen level monitored
Food monitored
Water is filtered
How are enzymes used to cut up DNA or join DNA together?
Restriction Enzymes recognise specific sequences of DNA and cut the DNA at these points
Ligase enzymes join the pieces back together
This is know as recombinant DNA
What’s a vector?
Something used to transfer DNA into a cell
What are the 2 types of vectors?
Plasmids
Viruses
What’s a plasmid?
Molecules of DNA which can be transferred between bacteria
Why are viruses a vector?
They insert DNA into the organisms they infect
How does genetic engineering work?
DNA you want to insert and the vector DNA are cut upon using restriction enzymes
They are then mixed together using ligase enzymes, making recombinant DNA
The recombinant DNA is added to the required cells
These cells can make the protein you want
What’s a transgenic cell?
A cell which contains genes from another species
Benefits of genetically modified plants?
More productive
Insect resistant so no pesticide
Negatives of genetically modified plants?
Could affect food chains
Could affect human health
Genes may get out into the wild
What’s micro propagation?
Cutting from plants are grown in petri dishes with the right nutrients then planted in soil
How’s cloning an adult mammal done?
Cell nucleus from grown animal placed in an egg cells, then shocked to trigger meiosis, placed in Uterus
Advantages to cloning?
Animals that produce medicine in their milk could be cloned
Animals that have organs that could be transplanted can be cloned
Farmers don’t have to wait till breeding season, infertile animals can also be cloned
Disadvantages to cloning?
Animals not as healthy
Consequences were not aware of
Expensive and time consuming
