2.7 genetic control of metabolism

Question 1

Wild strains

Answer 1

Microorganisms which exist in their natural form + environment - not tampered by humans.

Question 2

Wild strains use

Answer 2

They are selected for use in industry for desirable genetic traits.
Or to undergo mutagenesis and recombinant DNA to improve traits

Question 3

Mutagenesis

Answer 3

Where mutations are synthetically produced.

Question 4

How are mutations increased

Answer 4

Mutagenic agents such as
Radiation
Mutagenic chemicals

Question 5

Mutations features

Answer 5

Rare
Random and spontaneous
Detrimental

Question 6

Use of mutagenesis

Answer 6

To provide organisms with advantageous and new alleles, through mutation, to be beneficial to humans.

Question 7

Recombinant DNA technology

Answer 7

The transfer of gene sequences from one organism to another using vectors

Question 8

Vectors def

Answer 8

A DNA molecule used to carry foreign genetic information into another cell.

Question 9

Restriction endonuclease definition

Answer 9

The enzyme which is used to cut open vector at the restriction site and cut out specific genes from chromosomes in recombinant DNA

Question 10

Restriction endonuclease features

Answer 10

The same restriction endonuclease must be used to cut both the plasmid and the gene, to ensure that the ends are complimentary to each other, these ends are called sticky ends.

Question 11

Ligase use in recombinant DNA

Answer 11

To fuse together the desired gene and plasmid in recombinant DNA .

Question 12

Process of genetic engineering/ recombinant DNA

Answer 12

A plasmid is removed from a bacteria/ yeast cell
The restricted site of plasmid is cut open using restriction endonuclease
Foreign gene is cut out of a chromosome by the same restriction endonuclease enzyme.
The foreign gene and plasmid are fused together by the ligase enzyme to produce a recombinant plasmid.
The recombinant plasmid is then inserted into a new bacterial/yeast host cell.

Question 13

Criteria of effective vectors

Answer 13

Restriction sites
Regulatory sequences
Origin of replication
Selectable markers

Question 14

Restriction sites definition

Answer 14

The site that contains target sequences of DNA where specific restriction endonuclease cuts, and foreign genes are inserted.

Question 15

Purpose of restriction site

Answer 15

To be the location where foreign DNA is transferred into.

Question 16

Regulatory sequence definition

Answer 16

The site which controls gene expression of the vectors genes and foreign genes.

Question 17

Origin of replication

Answer 17

The site which allows for self replication without the foreign DNA being altered.

Question 18

Selectable markers

Answer 18

A gene which protects a a vector or microorganism from selective agents such as antibiotics.

Question 19

Use of vectors

Answer 19

Recombinant DNA
to prevent harmful microorganisms from surviving and causing harm to humans.

Question 20

Why are artificial chromosomes more effective than plasmids

Answer 20

Artificial chromosomes and plasmids both contain the same features which make them effective vectors - however artificial chromosomes are larger and have a larger restriction site and therefore can carry more foreign DNA and larger genes from donor to host.

Question 21

DNA of eukaryotes

Answer 21

Contains introns and exons

Question 22

DNA of bacteria

Answer 22

Only contains exons

Question 23

Why is yeast more effective than bacteria as a vector (referring to their plasmid )

Answer 23

Because polypeptides may become incorrectly folded if eukaryotic DNA is expressed in bacteria. (Prokaryotic)