4.5 DNA Cloning

Question 1

what is genetic engineering

Answer 1

cloning genes and then using them to alter the genome of viruses and cells

Question 2

what is gene cloning

Answer 2

production of many identical coopies of a single gene

Question 3

what is gene therapy

Answer 3

when cloned genes are used to modify a human

Question 4

what are transgenic organisms

Answer 4

organisms with foriegn DNA or genes inserted to them

Question 5

why do biologists clone genes

Answer 5

• produce large quantities of gene protein product (insulin)
• learn how a cloned gene codes for particular protein
• use gene to alter the phenotype of other organisms in a beneficial way

Question 6

what is recombinant DNA (vector and plasmid)

Answer 6

rDNA: contains DNA from two or more sources (human and bacteria cell)
need a vector (piece of DNA that can be manipulated to that foreign DNA can be added to it), a common vector is plasmid (small accessory rings of DNA from bacteria not part of the bacteria chromosome abd can self replicate)

Question 7

describe the two enzymes needed for recombinant DNA

Answer 7

• restriction enzymes: cut vector DNA (hundreds in bacteria)

- DNA ligase: seal DNA fragments

Question 8

why are the ends of DNA called “sticky ends”

Answer 8

they can bind a piece of foreign DNA by complementary base pairing beacause they are both cleaved from the same restictive enzyme

Question 9

what happens after bacteria takes up recombinant plasmids

Answer 9

after plasmid replicates, foreign DNA also replicates and gene is then clones

Question 10

describe cloning a human gene and bacteria

Answer 10

1. restrictive enzyme cleaves DNA
2. DNA ligase seals human gene and plasmid
3. host cell takes up recombined plasmid
4. gene cloning occurs