Chapter 21: Biotechnology And Genetic Modification Flashcards
Discuss why bacteria are useful in biotechnology and genetic modification
-rapid reproduction rate
-their ability to make complex molecules
-few ethical concerns over their manipulation and growth
-the presence of plasmids
role of anaerobic respiration in yeast during the production of ethanol for biofuels
the conversion of glucose into ethanol and carbon dioxide in the absence of oxygen( fermentation)
ethanol produces can be collected, purified and used as biofuel
the role of anaerobic respiration in yeast during bread-making
The carbon dioxide released in anaerobic respiration of yeast is used by bakers to make bread rise.
Describe the use of pectinase in fruit juice production
to break down pectin, enhancing juice production and clarity.
pectin is found inside plant cell walls.
Once pectin is broken down, the cell walls break more easily and more juice can be squeezed out of the fruit.
describe the use of biological washing powders that contain enzymes
contain enzymes similar to the digestive enzymes
-Quickly breaking down to small soluble molecules that dissolves in washing water
-effective at lower temperatures, meaning less energy
-used to clean delicate fabrics not suited for high temperature
Explain the use of lactase to produce lactose-free milk
Milk can be made lactose free by adding the enzyme lactase to it and leaving it to stand for a while to allow the enzyme to break down the lactose.
Describe how fermenters can be used for the large-scale production of useful products by bacteria and fungi
Fermenters are containers used to grow (‘culture’) microorganisms like bacteria and fungi in large amounts by carefully controlling conditions
These can then be used for many biotechnological processes like producing genetically modified bacteria
explain the conditions that need to be controlled in a fermenter
temperature, pH, oxygen, nutrient supply and waste products
Describe genetic modification
changing the genetic material of an organism by removing, changing or inserting individual genes
Outline the process of genetic modification using bacterial production of a human protein
(a) isolation of the DNA making up a human gene using restriction enzymes, forming sticky ends
(b) cutting of bacterial plasmid DNA with the same restriction enzymes, forming complementary sticky ends
(c) insertion of human DNA into bacterial plasmid DNA using DNA ligase to form a recombinant plasmid
(d) insertion of recombinant plasmids into bacteria
(e) multiplication of bacteria containing recombinant plasmids
(f) expression in bacteria of the human gene to make the human protein
Outline examples of genetic modification:
(a) the insertion of human genes into bacteria to produce human proteins
(b) the insertion of genes into crop plants to confer resistance to herbicides
(c) the insertion of genes into crop plants to confer resistance to insect pests
(d) the insertion of genes into crop plants to improve nutritional qualities
advantages of genetically modifying crops
- reduced use of chemicals such as herbicides and pesticides which is better for the environment, cheaper and less time-consuming for the farmers
- increased yields from the crops as they aren’t competing with weeds for resources or suffering from pest damage
disadvantages of genetically modifying crops
- increased costs of seeds poorer farmers can’t compete with larger
- increased dependency on certain chemicals, such as the herbicides that crops are resistant to - often made by the same companies that produce the seed and more expensive to buy
- risk of inserted genes being transferred to wild plants by pollination
- reduced biodiversity bc there are fewer plant species when herbicides have been used
- some research has shown that plants that have had genes inserted into them do not grow as well as non-GM plants
