2. Evolution Pt5 Flashcards
Explain genetic engineering
This involves modifying the genetic material of an organism by taking a gene from one organism and transferring it into another
Give one example of genetic engineering that can help us treat diabetes
- the gene for producing human insulin can be placed into a bacteria
- so it produces the human hormone for us to treat diabetes
Explain the genetic engineering with human insulin and bacteria that treats diabetes
- The human insulin gene is ‘cut out’ of a human cell by an enzyme
- A ring of DNA from a bacteria, called a plasmid, is taken out and split open with the same enzyme
- The insulin gene is inserted into the vector (the plasmid) with another enzyme and put back into the bacteria
- The bacteria multiply and realise the insulin which can be collected
Explain how genetic modification works with modifying crops to be herbicide (weed killer) resistance
- The gene for herbicide resistance is ‘cut out’ of the DNA of another resistance plant with an enzyme
- A plasmid from a bacteria is taken out and split open with the same enzyme
- The resistance gene is inserted into the vector (the plasmid) with another enzyme and inserted into embryonic cells of a farmer’s plant crop
- The plants are cloned in a culture then allowed to grow into a large number of plants
- When the farmer sprays herbicide it only kills the weeds the crops are resistance
Give advantages of using genetic modification to modifying crops to be herbicide (weed killer) resistance
- it reduces competition for light, water and nutrients
- maximising the growth of the crops and improving the farmers yield
Explain how genetic modification works in gene therapy to cure genetic diseases in adults (both methods)
Method 1
- a healthy gene is inserted into a harmless virus
-the virus ‘infects’ the person’s cells, delivering the healthy gene to cure the disease
Method 2
-adult stem cells are removed from the patient
-they’re infected with a harmless virus carrying the healthy gene
-the GM (genetically modified) are reintroduced to the patient to fix the problem caused by The disease
Explain how genetic modification is used to modify embryos to prevent disease
- the healthy gene is added to a fertilised egg by injection. It will insert insert into the egg’s genetic material
- when the egg divides, a cell is removed and checked to see if the gene instead I geeks properly, if it has the other cells will be implanted into the mother uterus
- a healthy child will be born the new gene will be present in every cell and its offspring will have it to
5 advantages of genetic engineering
- bacteria will produce proteins such as insulin, identical to human ones, which is better the extracting it from pigs and cows
- engineered plants and animals can grow faster or be resistant to pests and herbicides increasing yield
- extra vitamins could be added to foods to prevent diseases
- crops could grow in places that struggle to grow
- healthy genes could be inserted into diseased cells to treat human genetic diseases
4 disadvantages of genetic modification
- the long term danger is that some genes may be passed on to pests, such as insects becoming resistant to pesticides (weeds resistant herbicides)
- many GM crops are produced in fertile,no farmers have to buy new seeds each year, so companies that cell them have a lot of control
- there infertility could spread to wild plants damaging the Eco-system
- people might want to manipulate the genes of there children so they have certain characteristics, designer babies would change the course of natural selection and alter variation in the human race
What des DNA stand for?
Deoxyribonucleic acid
What’s DNA?
- a polymer made from 4 different nucleotides
- each nucleotide consists of a common sugar & phosphate group with one of four different bases attached to the sugar
What’s a gene?
-the section of DNA that codes for 1 entire protein
The ……… of DNA that you have can define your……
Sequence
Characteristics
Why do you have 2 copies of every chromosome?
One from each parent you usually inherit 2 copies of each gene, possible as different alleles
Define alleles?
Versions of the same gene
Define genome?
The complete set if genes for an organism
Explain the human genome?
- completely sequenced in 2008
- identifying all of the bases in all our 21,000
What has the human genome helped with?
- identifying the genes linked to cancer
- understanding of how to a variety of diseases
- trace the migration of early humans across the globe
What are ethical concerns with the genome project?
- use it in embryo screening for designer babies
- life insurance companies
- religious people are against it
- discrimination against employers
- improves genetic testing (people are against this)
What are the 4 bases in DNA?
A
C
G
T
What makes an amino acid?
- a sequence of 3 bases is used to code an amino acid
- the order of bases controls the order in which amino acids are assembled to produce a particular protein
A DNA polymer is made up of…
Repeating nucleotide units
What do all 23 chromosome pairs do?
- 22 control characteristics
- but one pair carries the genes that determine the sex
Polydactyl and cystic fibrosis are caused by what?
They’re inherited, the child inherits certain alleles
What causes variation?
- genes that have been inherited (genetic cause)
- the conditions in which they’ve developed (environmental cause)
- a combination of genes and the environment
What’s variation?
Differences in the characteristics of individuals in the population
