Use of biological resources

• What is the purpose of glasshouses and polyethene tunnels in crop production?


  They protect crops from harsh weather conditions.
• How do glasshouses and polyethene tunnels affect the rate of photosynthesis?


  They increase carbon dioxide levels, which enhances the rate of photosynthesis.
• Why is it beneficial for plants to be in a warm environment within glasshouses?

  Heat is trapped from the Sun, allowing enzymes to reach their optimum temperature.
• What is one way that glasshouses protect plants from pests?


  They prevent pests that can damage plants or carry diseases.
• How can carbon dioxide levels be increased in crop production?


  By burning paraffin lamps.
• What role does temperature play in the rate of photosynthesis?


  Higher temperatures allow enzymes to work at their optimum, increasing the rate of photosynthesis.
• What do fertilizers provide to plants?


  Nutrients that allow plants to grow faster.
• How do water-soluble minerals in fertilizers benefit plants?


  They can be absorbed into the plant roots by active transport.
• What are nitrates required for in plants?


  To make amino acids for proteins.
• What is the role of phosphates in plants?


  They are required for respiration and root growth.
• Why is potassium important for plants?


  It is needed for the growth of flowers and fruit.
• What is pest control in agriculture?


  Using pesticides or biological control to prevent insects from eating the plants.
• What types of pesticides are included in pest control?


  Fungicides, herbicides, and insecticides.
• What is one advantage of using pesticides?


  They are quick and efficient in controlling pests.
• What is a disadvantage of using pesticides?


  Organisms can develop resistance to them.
• What is bioaccumulation in the context of pesticides?


  It can make pesticides toxic to other organisms in the food chain.
• Why must pesticides be continuously applied?


  Because organisms can develop resistance and they are non-specific.
• What type of respiration does yeast use to make bread rise?


  Anaerobic respiration.
• What is the chemical equation for the anaerobic respiration of yeast?


  $C_6H_{12}O_6 \rightarrow \text{Ethanol} +$$\text{CO}_2$
• What causes the bread to rise during the fermentation process?

  The carbon dioxide bubbles produced by yeast.
• What are the steps to investigate the role of anaerobic respiration by yeast in different conditions?


  1. Dissolve sugar in boiled water.
  2. Mix yeast with the sugar solution in a boiling tube.
  3. Add a layer of oil to prevent oxygen from entering.
  4. Connect the boiling tube to a test tube of lime water.
  5. Count the number of bubbles over a set time.
• What is the role of Lactobacillus in yoghurt production?


  It breaks down lactose to form lactic acid.
• How does lactic acid affect the milk in yoghurt production?


  It lowers the pH of the milk, denaturing proteins for texture.
• What are the steps in the yoghurt production process?

  1. Sterilize all equipment.
  2. Heat milk to 72°C for 15 seconds (pasteurization).
  3. Cool the milk and add Lactobacillus.
  4. Incubate at around 40°C in a fermenter.
  5. Produce thickened yoghurt and add flavoring before packaging.
• What is the purpose of an industrial fermenter?


  To grow bacteria and fungi in large amounts.
• Why are aseptic conditions important in an industrial fermenter?


  To prevent contamination by other microorganisms.
• What is required for microorganisms to thrive in a fermenter?


  Nutrients, optimum temperature, and pH.
• What is the purpose of agitation in a fermenter?


  To ensure even distribution of nutrients, oxygen, temperature, pH, and microorganisms.
• What is one method used to maintain water quality in fish farming?


  Filter water to remove waste and harmful bacteria.
• How is intraspecific predation controlled in fish farming?


  By separating fish by size and age to prevent competition.
• What is the purpose of controlling interspecific predation in fish farming?


  To prevent competition between different species.
• How are diseases controlled in fish farming?


  By administering antibiotics to increase survival chances.
• What is done to remove waste products in fish farming?


  Water is filtered to remove waste feces.
• How is the quality and frequency of feeding controlled in fish farming?


  Fish are fed frequently but in small amounts to avoid overeating and waste.
• What is selective breeding?


  Choosing organisms to breed for desirable characteristics.
• What is a potential problem with selective breeding?


  It can lead to inbreeding and a reduced gene pool.
• How does a reduced gene pool affect a species?


  It increases the risk of extinction if the environment changes or diseases arise.
• What is a consequence of a small gene pool in selective breeding?


  There is a greater chance of genetic defects in offspring.
• What is genetic engineering?


  Modifying the genome of an organism by introducing a gene from another organism.
• What are some applications of genetic engineering in plants?


  Engineering for disease resistance or larger fruits.