Genetic Modification and Other Technologies Flashcards
Give the model answer to selective breeding (5)
1) A male and female with the desired characteristics are chosen by a farmer
2) These offspring are allowed to breed (artificial insemination may be used)
3) The offspring should inherit the desired characteristics
4) The offspring which then show the best of these features are selected and bred together
5) This is repeated over a number of generations
What is selective breeding
Selecting the parents with the desired characteristics, allowing them to breed and be repeated over many generations
Why is the Belgian Blue such a big cow
Gene that regulates muscle growth has been removed
How is selective breeding different to natural selection
Natural selection = competition for survival will select who survives
Selective breeding = faster and done artificially
What is genetic engineering
Changing the genetic material of an organism by taking a gene from one organism and inserting it into another
What is a vector
Carrys (DNA)
e.g Plasmid
What does a bacteria cell have instead of a nucleus
Single circular chromosome
Describe the order of genetic engineering bacteria cells (8)
1) Find (human insulin) gene
2) Cut out gene using restriction enzyme
3) Find a vector (Plasmid in bateria)
4) Cut open vector with same restriction enzyme
5) Insert gene of interest into vector. Ligase sticks the two together
6) This produces recombinant DNA
7) The bacterium is now referred to as transgenic as it contains genes from a different species.
8) The bacteria can be grown in a fermentor and produce human insulin
What is recombinant DNA
Genes from more than 1 species
What is Transgenic
Contains DNA from more than 1 species
Give 4 vectors
Plasmids
Viruses
AgroBacterium
Gene Gun
What does a plasmid do
- From bacteria
- Used as delivery vehicles for foreign DNA
- Easily passed between bacteria
What do viruses do
Inserts genetic material into other organisms
What does Agro-Bacterium do
Uses horizontal gene transfer to cause tutors in plants
Naturally infects plants
What does a gene gun do
Microscopic material are used as ‘bullets’ to deliver DNA into callus cells
Why is it harder to genetically engineer plants
No natural plasmid
Multicellular
What is golden rice and how was it made
Rice + Daffodils
Full of vitamin A
Give some traits that you could genetically engineer into crops
Frost resistant Heat resistant Better taste Different colours Increased yield
Give the pros and cons of golden rice
Pros = cure for vitamin A deficiency
Cons = Only big companies can afford to use it which puts smaller ones at risk
Give some pros of using GE in plants
Can be given natural insect killing genes - no need to spray crops with toxic insecticides
Can produce better + bigger crops
Farmers can use less weed killers and pesticides
Can make people living in developing countries healthier - adding vitamins to staple foods
Could reduce the number of starving people in the world
Give some cons of using GE in plants
Some insects can become resistant to the natural insect repellent used by the GM crop
Companies who make the seed might make them very expensive - limiting use in poorer countries
The gene may spread from GM plant to tother species
Might give people serous food allergies / side effects
May reduce the lifespan of animals that eat them, including humans
What is a clone
Genetically identical organism
Give a natural clone
Spider plants (mitosis)
Describe cloning plants by cutting
A branch from the parent plant is cut off, lower leaves removed and the stem planted in damp compost
Plant hormones are often used to encourage new roots to develop
The cutting is usually covered in a clear plastic bag at this stage to keep it moist and warm
After a few weeks, new roots develop and a new plant is produced. The method is easy enough for most gardeners to do successfully.
Give the cons of cutting
Limited by how many copies you can make
What is Micropropagation (5)
Small amounts of parent tissue or a number of cells are taken
The plant material is transferred to plates containing sterile nutrient agar jelly
Plant hormones are added to stimulate the cells to divide
Cells grow rapidly into small masses of tissue
The tiny plantlets are transferred into potting trays where they develop into plants
How would you clone a sheep (model answer) (7)
1) Take an egg cell from the organism
2) Remove the haploid nucleus from the egg cell to produce an inoculated egg cell
3) Take a body cell from the desired organism that you want to clone
4) Remove the diploid nucleus from this cell
5) Using an electric shock, fuse the two cells together
6) It will start to divide by mitosis to form an embryo
7) Place the embryo into a uterus of a surrogate mother
Give two pros of cloning
- Can quickly replace the desired gene of a certain animal (lots of wool)
- Conservation work
Give two cons of cloning
Reduce variety
Short life span
