Chapter 13: Biotechnology

Question 1

What is a restriction enzyme?

Answer 1

Bacterial enzymes that restrict the duplication of infecting viruses by cutting viral DNA.

Question 2

What is the recognition site?

Answer 2

Where an enzyme cuts the DNA at a point where there is a specific sequence of bases.

Question 3

What are transgenic organisms ?

Answer 3

Those whose genome has been altered by the transfer of a gene or genes from another organism.

Question 4

What is Recombinant DNA Technology?

Answer 4

Involves the introduction of DNA into cells, where the DNA is foreign to that organism or has been modified in some way.

Question 5

What is the process of ligation ?

Answer 5

Ligation is the joining of short DNA strands during replication via the bacterium Escherichia Coli (E.Coli)

Question 6

What is straight cut ?

Answer 6

When the enzyme makes a clean break across the two strands of DNA to produce a blunt end.

Question 7

What is a blunt end ?

Answer 7

A blunt end is when both strands terminate in a base pair.

Question 8

What is a staggered cut ?

Answer 8

Results in fragments with sticky ends.

Question 9

What are sticky ends ?

Answer 9

A sticky end is a stretch of unpaired nucleotides in the DNA molecule that overhang at the break in the strands.

Question 10

What is ligase ?

Answer 10

An enzyme capable of combining two small components of single stranded DNA into a single structure.

Question 11

What are plasmids ?

Answer 11

Small, circular strands of DNA that are distinct from the main bacterial genome; it is comprised of only a few genes and is able to replicate independently within a cell.

Question 12

What are vectors ?

Answer 12

A bacterial plasmid, a viral phage or other such agent used to transfer genetic material from one cell to another.

Question 13

What is a Phage ?

Answer 13

A virus that infects bacteria.

Question 14

What are uses of Recombinant DNA Technology (RDT)?

Answer 14

RDT has had an enormous impact on the diagnosis and treatment of diseases and genetic disorders. It has also enables the manufacture of large quantities of pure protein for many medical products including insulin, growth hormone .

Question 15

What is DNA sequencing ?

Answer 15

The determination of the precise order of nucleotides in a sample of DNA.

Question 16

What are some diseases that can be determined by DNA sequencing ?

Answer 16

Sickle cell anemia, cystic fibrosis, and some forms of cancer.

Question 17

What are profiling techniques ?

Answer 17

Electrophoresis: DNA pieces placed on a bed of semi-solid gel and an electric current was passed through electrodes at either end. The small DNA pieces move faster than the larger ones, resulting in a ‘band’ pattern; this banding pattern is a DNA profile.

Question 18

What is PCR ?

Answer 18

Polymerase chain reaction (PCR) is used to artificially multiply segments of DNA through a series of repeated cycles of duplication using an enzyme called DNA polymerase.

Question 19

What are hereditary diseases ?

Answer 19

A hereditary disease is caused by defective genetic information being transmitted from parents to their children.Such diseases are often passed on within families over many generations.

Question 20

Describe gene therapy.

Answer 20

Gene therapy aims to cure genetic abnormalities by replacing faulty genes with healthy ones. It is a way of using the genes themselves as the treatment.