7.3 Gene Technology Flashcards
1
Q
define genetic engineering/ modification
A
- changing the genetic material of an organism by inserting genes from one organism into the genetic material of another organism
2
Q
what is recombinant DNA
A
- DNA that has been artificially formed by combining constituents from different organisms
3
Q
What is the first step of producing recombinant DNA
A
- take an mRNA molecule transcribed from the required gene and use reverse transcriptase to produce complementary DNA
OR - restriction endonucleases are used to cut up DNA at restriction sites, sometimes leaving sticky ends (when one strand is longer than the other), which makes it easier to attach new pieces of DNA to them
4
Q
What is THE REST of the process of making recombinant DNA
A
- integrate the new gene into the vector, plasmids are frequently used, DNA ligase is used to join pieces of DNA together
- Once the plasmid is incorporated into the host nucleus, it forms part of the new recombinant DNA of the genetically engineered organism
- successfully transformed cells can be identified, isolated and cultivated
5
Q
How do researchers identify transformed organisms
A
- they transfer marker genes along with the desired DNA so they can identify the organisms in which the transformation has taken place
6
Q
what is “replica plating” and what is it used for
A
- it is used to identify recombinant cells
1. grow identical patterns of bacterial colonies on plates with different media
2. identify the colonies that can survive in the presence of a particular antibiotic, or without a certain nutrient
3. these are the genetically modified bacteria
7
Q
what is a vector
A
- something that transfers the required gene, along with any marker genes into new cells
- targets the right cells and ensures that the desired gene is incorporated into the hosts genetic material
- they can recombine to the host chromosome or just stay in the cell and be autonomous
8
Q
what vectors are used in the formation of GM plants 9and in most things altogether)
A
- plasmids
9
Q
which vector techniques tend to be used in human cells
A
- gene guns- when DNA is shot into he cell at high speed, some cells survive
- Viruses- a harmless virus is engineered to carry a desired gene
- Liposome wrapping- gene is wrapped around liposomes, liposomes fuse with cell membrane and deliver it to cytoplasm
10
Q
what is the most common problem with vectors, and explain which is worst and best
A
- the big challenge is getting the DNA into the right place to be transcribed
- liposomes are the worst and viruses are the best
- because viruses inserting DNA into the DNA of an organism is just how viruses work
- however they can cause immune responses sometimes
11
Q
what’s a knock out organism and what is it used for
A
- used for genetic research, organisms that have had some genes silenced
- when one or more genes in an organism are silences or ‘knocked out
- so they no longer function
12
Q
describe the process pf the genetic modification of soya beans
A
- oil from soya beans is what is widely used
- soya beans contain a lot of linoleic acid which oxidises easily , which makes the oil go off
- it is also polyunsaturated fatty acid, whilst others in soy beans (oleic acid) are monounsaturated and better for your health
- scientists have produced GM modified soya beans that have a different balance of fatty acids
- a lot of oleic acid and less linoleic acid
13
Q
how has the genetic modification of soya beans been used to improve production
A
- more oleic acid and less linoleic acid means that the soya beans would have more health benefits and they lats longer
14
Q
why are crops genetically modified
A
- to reduce their vulnerability to to disease, pests and adverse growing conditions
15
Q
why are knockout mice used
A
- because there is an ethical limit to how much investigation that scientists can carry out on people, so mice act as substitutes
