Food Production Flashcards
What is fermentation?
Fermentation is when microorganisms break sugars down to release energy - usually by anaerobic respiration.
How do you make yoghurt?
1) The equipment is sterilised
2) The milk is pasteurised
3) Lactobacillus bacteria are added, and the mixture is incubated
4) The bacteria ferment the lactose sugar in the milk to form lactic acid
5) Lactic acid causes the milk to clot, and solidify into yoghurt
6) Flavours and colours are sometimes added and the yoghurt is packaged
What are the optimum conditions for plant growth?
Sunlight, heat, water, oxygen
What are the benefits of growing plants in a polythene tunnel or glasshouse?
It allows farmers to control the conditions, they can use artificial heating, lighting and release carbon dioxide into the air. They protect plants from wind, rain and extreme temperatures. They are also big enough for people and machines to work in.
Suggest why artificial fertilisers are known as NPK fertilisers
They contain elements like nitrogen, phosphorus and potassium
Describe the composition of a natural fertiliser
It’s made up of manure which is a mixture of faeces, urine and straw which contains high concentrations of nitrates and other mineral ions. Decay of the manure by microorganisms releases the ions into the soil.
Give an example of a leguminous plant
Beans/peas
Explain the role of leguminous plants in crop rotation
Legumes have root nodules containing nitrogen fixing bacteria. This means they are able to add nitrates to the soil.
Name four food products that are made using microorganisms
Brad, yoghurt, cheese, vinegar
What role does yeast play in the production of beer?
Sugar from plant material is converted into ethanol and carbon dioxide by fermentation. The enzymes found in single - celled fungi - yeast are the natural catalysts that can make this process happen.
What type of microorganism is bread?
Fungus (yeast)
What type of microorganism is cheese?
Bacteria
What type of microorganism is vinegar?
Bacteria (acetobacter)
What type of microorganism is soy sauce?
Fungus (yeast)
What type of microorganism is SCP (mycroprotein)?
Fungus
What type of microorganism is beer?
Yeast
What type of respiration takes place in bread?
Anaerobic
What type of respiration takes place in cheese?
Aerobic
What type of respiration takes place in vinegar?
Aerobic
What type of respiration takes place in soy sauce?
Anaerobic
What type of respiration takes place in SCP (myco protein)?
Anaerobic
What type of respiration takes place in beer?
Anaerobic
Label a diagram of a fermenter
…
Give the definition of a pest
An organism that causes damage to plants animals
Give the definition of pesticide
A chemical used to kill pests
What are artificial pesticides and how are they used?
A chemical sprayed over crops to kill pests
What are the main problems with artificial pesticides?
Reduces biodiversity
Bio accumulation - poison builds up higher up the food chain
Killing lots of different types of insect in an area will reduce the amount of food available for animals to eat
What are the main problems with biological control?
It’s difficult to control the predators and parasites in open fields. They may move quickly away and eat other prey. They may disrupt the food web by outcompeting other organisms. They may not have a native predator.
Explain how temperature is controlled in the fermenter?
The temperature recorder monitors the temperature and the cooling jacket removes excess heat.
Explain why temperature must be controlled in the fermenter?
Because excess heat released during respiration may denature the enzymes making them unable to work. Respiration produces heat.
Explain the purpose of the paddles in the fermenter
The heat must be evenly distributed for the enzymes to work otherwise the cells at the bottom of the fermenter will boil and the cells at the top will freeze.
Other than temperature, name one condition that needs to be controlled in a fermenter and state why it needs to be controlled
Oxygen for respiration
Name a product that could be produced in this type of fermenter
Insulin, penicillin, mycroprotein
Name the group of organisms that includes yeast
Fungi
What is meant by the term anaerobic?
No oxygen is present
What is intraspecific competition?
Intraspecific competition is the competition between individuals of the same species
What is interspecific competition?
Interspecific competition is the competition between individuals of different species
