B1: Cloning and Genetic Engineering Flashcards
1
Q
How can clones be made through the process of cutting?
A
- Cuttings from a good parent plant are taken and then replanted to produce genetically identical copies of the parent plant.
2
Q
How can clones be made through tissue cultures?
A
- A few plant cells are put in a growth medium with hormones and they grow into new plants.
3
Q
What are the advantages of the cutting process and tissue cultures?
A
- Plants produced from cutting can be produced quickly and cheaply
- Plants produced through tissue cultures can be made very quickly, in little space and can be grown all year round.
4
Q
How are animal clones made?
A
Through embryo transplants.
5
Q
What is the process of embryo transplants?
A
- Sperm cells and egg cells are taken from animal with desired characteristics.
- The sperm is used to artificially fertilise the egg
- The embryo splits many times before any cells become specialised
- These cloned embryos can then be implanted into lots of other mothers where they will grow into genetically identical offspring. They will also be genetically identical to the parent cells.
6
Q
What is the advantage of animal cloning?
A
‘Desired’ or ‘ideal’ offspring can be produced fairly easily each year. Many offspring can be produced too.
7
Q
Explain the process of adult cell cloning.
A
- An unfertilised egg is taken and its genetic material (the nucleus) is removed.
- The nucleus from an adult body cell is implanted into the unfertilised egg.
- The egg cell is then stimulated by an electric shock, which makes it begin dividing like an embryo.
- When the embryo becomes a ball of cells, it is implanted into an adult female to grow into a genetically identical copy (a clone) of the original adult body cell.
8
Q
What are the issues surrounding cloning?
A
- It reduces the gene pool- there are fewer alleles in a population so if a new disease appears the entire population could be wiped out.
- Cloned organisms may not be as healthy as the normal ones (Dolly the sheep had arthritis)
- People are worried that if humans were cloned, there would be many unsuccessful attempts compared to the successful ones.
9
Q
What are the benefits of cloning?
A
- The study of clones could lead to greater understanding of the development of the embryo and of ageing and age-related disorders
- It could be used to preserve endangered species
10
Q
Explain the process of genetic engineering.
A
- A useful gene is ‘cut’ from one organism’s chromosome using enzymes
- Enzymes are then used to cut another organism’s chromosome.
- The useful gene is inserted into the other organism’s chromosome using enzymes.
11
Q
What uses does genetic engineering have?
A
- Human insulin gene can be inserted into bacteria to produce human insulin. The insulin produced is purified and used by people with diabetes.
- GM crops have had their genes modified to make them resistant to viruses, insects or herbicides
- Sheep have been genetically modified to produced drugs in their milk that can be used to treat human diseases.
- Scientists are trying to treat genetic disorders by replacing faulty genes with working genes. This is gene therapy.
12
Q
What are the pros of GM crops?
A
- It can increase the yield of a crop, making more food
- Gm crops could be engineered to contain nutrients that are missing from people’s diets, especially in developing countries
- GM crops are already being grown elsewhere in the world, often without any problems
13
Q
What are the cons of GM crops?
A
- Some people believe growing GM crops will affect the number of weeds and flowers- reducing farmland biodiversity.
- Not everyone is convinced GM crops are safe. People are worried they could develop allergies to the food
- Transplanted genes could get into the natural environment creating a new resistant plant/weed.
