Biotechnology and Genetic Modification. Flashcards
Why are bacteria useful in biotechnology?
Bacteria are useful in biotechnology and genetic modification due to their rapid reproduction rate and their ability to make complex molecules.
What do bacteria contain which new genes can be inserted, removed, or changed?
Also are there any concerns over the manipulation of the DNA of bacteria?
Bacteria contain plasmids which are circular rings of DNA into which new genes can be inserted, removed, or changed. There are also no ethical concerns about manipulating the DNA of bacteria.
What is yeast?
What two roles does it have in bread making and ethanol production?
Yeast is a microorganism that can respire anaerobically (without oxygen) to release carbon dioxide.
This can be used in bread making to make the dough rise as bubbles of carbon dioxide form.
Ethanol is also released during this reaction, which can be used to make biofuels as an alternative to fossil fuels.
What is pectinase and what is it used for?
What is the role of pectinase in a plant?
What does adding pectinase do to juice?
Pectinase is an enzyme used in fruit juice production.
Pectinase breaks down pectin, which is found in plant cell walls and is used to hold the cell together.
Adding pectinase therefore breaks down these walls to release the contents of the cell, which increases the yield of fruit juice.
Describe the use of biological washing powders that contain enzymes in terms of:
What do they contain and what do they do?
What enzymes are present in biological washing powders and state what they do?
What do the enzymes do that allows for stains to be washed out easily?
What precautions need to be taken to prevent the inefficiency of the washing powder?
Biological washing powders contain enzymes to break down different molecules.
Amylases break down starch, lipases break down fats and oils, and proteases break down proteins.
Enzymes break these into smaller products that are water-soluble and thus can be washed out easily.
As enzymes are denatured at high temperatures and extreme pH, a lower temperature is needed, and the enzymes may not work in acidic or alkaline water.
What can the enzyme lactase be used to make?
What happens when lactase is added to milk which makes it safe to consume for lactose-intolerant people?
The enzyme lactase can be used to make lactose-free milk.
When lactase is added to milk, it breaks down the lactose into glucose and galactose, which can be safely consumed by lactose-intolerant people.
What can fermenters be used for?
Fermenters can be used for the large-scale production of useful products by bacteria and fungi, including insulin, penicillin, and mycoprotein.
Define genetic modification.
Genetic modification is the changing of 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: 6 steps.
- Isolation of the DNA making up a human gene using restriction enzymes, forming sticky ends.
- Cutting of bacterial plasmid DNA with the same restriction enzymes, forming complementary sticky ends.
- Insertion of human DNA into bacterial plasmid DNA using DNA ligase to form a recombinant plasmid.
- Insertion of recombinant plasmids into bacteria.
- Multiplication of bacteria containing recombinant plasmids.
- expression in bacteria of the human gene to make the human protein.
Give four examples of genetic modification.
- The insertion of human genes into bacteria to produce human proteins.
- The insertion of genes into crop plants to confer resistance to herbicides.
- The insertion of genes into crop plants to confer resistance to insect pests.
- The insertion of genes into crop plants to improve nutritional qualities.
What are the three benefits of using genetic engineering rather than the more traditional selective breeding techniques to modify crops:
- Organisms with the desired characteristics are produced more quickly
- Increased yields from the crops as they are not competing with weeds.
- Decrease the use of chemicals (pesticides or herbicides) - which may benefit other organisms.
What are the three disadvantages of using genetic engineering rather than the more traditional selective breeding techniques to modify crops:
- The reduction in biodiversity.
- Increased dependency on certain chemicals.
- Increased cost of seeds.
What are the advantages of using a fermenter?
The advantage of using a fermenter is that conditions can be carefully controlled (temperature, pH, oxygen, nutrient supply, and waste products) to produce large quantities of exactly the right type of microorganism.
Why is oxygen needed in a fermenter?
Oxygen is needed for aerobic respiration to take place.
Why is nutrient supply needed in a fermenter?
Nutrients are needed for use in respiration to release energy for growth and to ensure the microorganisms are able to reproduce.
