12 HARNESSING BIOLOGY Flashcards
Describe how to use selective breeding to get animals/plants with the desired characteristics
- Choose individulas with desired feature
- Let only these individuals reproduce
- Choose offspring with desired feature
- Led only these individuals reproduce
- Repeat for generations
How can polythene tunnels and glasshouses be used to increase the yield of certain crops
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- Transparent material allows suffecient natural light for photoysnthesis
- Addigtional lighting gives a ‘longer day’ during winter
- Greenhouse effect raises temperature of glasshouse
- Burning fossil fuels or wood raises temperature when external temperature is too low (also produced CO2 and water vapour)
- Water vapour maintains a moist atmosphere, so reduces water loss by transpiration
What is the aim of polythene tunnels and glasshouses
Increase the rate of photosynthesis and increase yield by finding optimum conditions
Advantages to using organic fertiliser
- Greater range of minerals
- Improves soil structure
- Less cost to farmer
- Releases minerals over a longer time
Disadvantages to inorganic fertiliser
- Can lead to eutrophication as it is soluble
- Requires regular application
Advantages to inorganic fertiliser
- Mineral ions release immediately - fast acting
- Contents known
- Easy to apply
Advantages to inorganic fertiliser
- Mineral ions release immediately - fast acting
- Contents known
- Easy to apply
Disadvantages to organic fertiliser
- Slow acting - must be decomposed first
- Bulkier - more difficult to apply
- May contain pests
Disadvantages to organic fertiliser
- Slow acting - must be decomposed first
- Bulkier - more difficult to apply
- May contain pests
How could pesticies damage ecosystems
Passed up the food chain, and become concentrated in the top tissues of carnivores
How does biological control work
- Use a predator
- Never eradicates the pest only reduces to a level where they no longer cuase significant economic damage
Advantages of pesticides
- Reduces pest population instantly
- Can kill the whole population of pests
Disadvantages of pesticides
- Cost - need regular application
- Not specific - could kill other organisms
- Pest can come resistant to chemical
- Chemical can conocentrate in all organisms higher up the food chain
Disadvantages of pesticides
- Cost - need regular application
- Not specific - could kill other organisms
- Pest can come resistant to chemical
- Chemical can conocentrate in all organisms higher up the food chain
Disadvantages to biological control
- Takes time to reduce pest population
- Not all population killed
- Expensive if re-populating is required
Disadvantages to biological control
- Takes time to reduce pest population
- Not all population killed
- Expensive if re-populating is required
Advantages to biological control
- Organism only introduced once - will reproduce
- Only one cost for initial introduction
- Pest specific
- Pest will not become resistant
- No effect on other animals in food chain
Advantages to biological control
- Organism only introduced once - will reproduce
- Only one cost for initial introduction
- Pest specific
- Pest will not become resistant
- No effect on other animals in food chain
How does increasing temperature in a glasshouse or polythene tunnel increase crop yield
- Enzymes and substrates have more kinetic energy and collide more often
- Rate of photosynthesis increases
- Increased crop yield
- At too high temperatures, the enzymes denature and rate decreases
How does increasing carbon dioxide concentration in a glasshouse of polythene tunnel increase crop yield
- There are more reacting molecules to collide with enzymes
- Increased rate of photosynthesis
- Increased crop yield
What do farmers do when feeding fish to maxamise effeciency of fish farming
- High lipid and protein food - promotes rapid growth
- Regular feeding wtih small ammounts - so most gets eaten
What is the problem with having several species of fish in one pond when fish farming
- Interspecific competition - different species will compete for food and some species may be wiped out
- Predation - carnivorous species will prey on other fish
What is the solution to interspecific competition and predation
- Place different species in different ponds
- Use nets to separate species and wild populations
- Place a cover over ponds to stop predation from birds
What is the solution to interspecific competition and predation
- Place different species in different ponds
- Use nets to separate species and wild populations
- Place a cover over ponds to stop predation from birds
What is the problems with having too many individuals of fish in one pond
- Intraspecific competition - Larger individuals will out-compete small individuals for food, or may even prey on them
- Infectious diseases - Parasites and pathogens will spread quickly if fish are too close together
What is the solution to intraspecific competition and infectious disease
- Seperate fish by age and size
- Remove dead or infected fish quickly
- Add antibiotics to the water to kill bacteria
How do fish farms affect the enviroment
- Fish may escape and out-compete or interbreed with local species, reducing biodiversity and upsetting the local ecoystem
- Parasites and pathogens can be intrduced into ecosystems
- Excess feed and waste from fish can cuase eutrophication and reduction of oxygen concentrations in water
How can waste be delt with fish farming
Vaccuming it out (clearing)
How can low O2 levels be delt with in fish farming
Bubbling oxygen through the water
How can low O2 levels be delt with in fish farming
Bubbling oxygen through the water
Anaerobic respiration in yeast equation
Glucose –> Ethanol + Carbon Dioxide
How does yeast help make bread
Bubbles of carbon dioxide gas expand the dough and help it rise
How does yeast help make alcoholic drinks like beer
Ethanol is made
Use of industrial jacket in industrial fermenters
Removes heat energy, stopping the fermenter overheating, and enzymes denaturing
Use of air filter in industrial fermenter
Filters air coming in, maintaining sterile conditions
Use of stirrers in industrial fermenter
Keep the broth well stirred to oxygenate all parts of the fermenter and stop micro-organisms growing
Use of growth medium in industrial fermenter
Contans all nescessary glucose and amino acids
Use of super-heated steam in industrial fermenters
Applied before fermenter’s used to kill unwanted micro-organisms
What bacteria is used to make yoghurt
Lactobacillus bulgaricus
How does lactobacillus bulgaricus make yoghurt
It respires anaerobically producing lactic acid that lower the pH of the milk. It coagulates the protein, changing the texture
How do fish farms affect the enviroment
- Fish may escape and out-compete or interbreed with local species, reducing biodiversity and upsetting the local ecoystem
- Parasites and pathogens can be intrduced into ecosystems
- Excess feed and waste from fish can cuase eutrophication and reduction of oxygen concentrations in water
What is the problems with having too many individuals of fish in one pond
- Intraspecific competition - Larger individuals will out-compete small individuals for food, or may even prey on them
- Infectious diseases - Parasites and pathogens will spread quickly if fish are too close together
What is the problem with having several species of fish in one pond when fish farming
- Interspecific competition - different species will compete for food and some species may be wiped out
- Predation - carnivorous species will prey on other fish
Advantages of pesticides
- Reduces pest population instantly
- Can kill the whole population of pests
How could pesticies damage ecosystems
Passed up the food chain, and become concentrated in the top tissues of carnivores
Advantages to using organic fertiliser
- Greater range of minerals
- Improves soil structure
- Less cost to farmer
- Releases minerals over a longer time
How can polythene tunnels and glasshouses be used to increase the yield of certain crops
- Transparent material allows suffecient natural light for photoysnthesis
- Addigtional lighting gives a ‘longer day’ during winter
- Greenhouse effect raises temperature of glasshouse
- Burning fossil fuels or wood raises temperature when external temperature is too low (also produced CO2 and water vapour)
- Water vapour maintains a moist atmosphere, so reduces water loss by transpiration
