Genetic Modification

Question 1

What is genetic modification

Answer 1

-changing the genetic material of an organism by removing, changing or inserting individual genes from another organism

Question 2

Advantages of genetic modification

Answer 2

-genes from different species can be combined, not restricted to alleles in natural population
-increase allele diversity, more disease resistance

Question 3

DNA meaning

Answer 3

-molecule composed of two strands, coiled to form a double helix, the strands being linked by a series of paired bases

Question 4

Proteins definition

Answer 4

Molecule made of amino acids, which could have one of man structural or functional roles in the body

Question 5

Restriction endonucleases

Answer 5

Enzymes which act like molecular scissors to cut out the required gene

Question 6

Gene

Answer 6

Section of the DNA which tells the cell to make a specific protein

Question 7

DNA ligases

Answer 7

Enzymes that act like molecular glue to join cut DNA pieces back together

Question 8

Transgenic

Answer 8

An organism which has ha genetic material from a different species transferred into its cells

Question 9

What is recombinant DNA

Answer 9

DNA from one organism combines with the DNA from another organism

Question 10

Vector

Answer 10

Structure which can be used to transfer genes in genetic engineering, such as plasmids

Question 11

Steps for genetic modification

Answer 11

1. Isolate plasmids from a bacterium
2. Cut out the gene you want to insert from the human cell it is found in using restriction endonucleases
3. Cut open the plasmid with restriction endonucleases
4. Use DNA ligase to recombine the desired gene with the plasmid
5. The recombinant plasmid is a vector, and is introduced into the bacteria
6. It produces insulin now/whatever

Question 12

Why do we use bacteria for insulin production

Answer 12

-no ethical issues
-same genetic code as organisms we take genes from (like humans for insulin), so they can ‘read’ it and produce the proteins
-they have plasmids

Question 13

Insulin

Answer 13

-Hormone produced by the pancreas
-lowers blood glucose levels by stimulating cells to absorb glucose from blood
-converts excess glucose into glycogen
Encourages body to use glucose for energy instead of fats

Question 14

How to genetically modify plants for resistance to pests

Answer 14

1. Remove a plasmid from a bacterium and break it open using restriction endonucleases
2. Use the same restriction enzymes to cut out a gene which codes for resistance to a pest
3. Use dna ligase to insert desired gene and join these together
4. Insert plasmid into the bacterium Agrobacterium
5. This is a common vector which inserts plasmids into plant cells and results in plants containing the desired gene to pest resistance
6. Agrobacterium does not affect cereals
7. A gene gun can be used to fire DNA at new plant tissues and produce transgenic plants

Question 15

Gene gun

Answer 15

-contain tiny pellets of gold coated with DNA that contains the desired gene
-fired directly into undifferentiated tissue

Question 16

Why are Agrobacterium useful

Answer 16

-plants need to have billions of cells that have the new gene
-Agrobacterium can pass on genes from plasmids to plant cells

Question 17

Pros and cons of using GM crops

Answer 17

+can tolerate bad conditions like infertile soil
+can produce plants with more nutrition
+improves crop yield
+less chemicals used, no bioaccumulation
-limited data on long term effect on human health
-GM crop seeds are more expensive, developing countries cannot afford them
-GM organisms can breed with wild organisms, their offspring can outcompete other plants, reducing biodiversity