Molecular Carrier Vector

Overview

Molecular carriers, such as plasmids, are utilized in biotechnology to introduce recombinant DNA into host cells. Plasmids, circular DNA molecules, can carry genes for antibiotic resistance and other traits. For example, plasmids like pSC 101 and pBR 322 contain antibiotic resistance genes that enable the selection of bacteria with specific genetic modifications. The use of vectors like plasmids is crucial in the process of gene manipulation and cloning.

Questions and Answers

1. What is a vector in biotechnology?

   A vector in biotechnology is a means by which recombinant DNA is introduced into a host cell.

2. What is a common type of vector used in biotechnology?

   A common type of vector used is a plasmid, which is a natural extra-chromosomal circular DNA molecule.

3. Can you give examples of plasmids with antibiotic resistance genes?

   Plasmid pSC 101 has an antibiotic resistance gene for tetracycline, while pBR 322 has antibiotic resistance genes for tetracycline and ampicillin.

4. How can gene insertion in plasmid pBR 322 help in separating bacterial colonies?

   Inserting a gene of interest in the tetracycline-resistant gene of plasmid pBR 322 enables the separation of colonies in a medium containing ampicillin.

5. What is the role of the restriction enzyme ECoRI in gene manipulation?

   The restriction enzyme ECoRI cuts specific sequences of nucleotides to produce sticky ends, aiding in gene manipulation.

Multiple-Choice Questions

1. What is a common type of vector used in recombinant DNA technology?

   a) Plasmid
   b) Virus
   c) Bacteriophage
   d) Fungus
   Answer: a) Plasmid

2. Which plasmid has antibiotic resistance genes for tetracycline as well as ampicillin?

   a) pSC 101
   b) pBR 322
   c) pUC 19
   d) pBluescript
   Answer: b) pBR 322

3. What is the function of the restriction enzyme EcoRI in recombinant DNA technology?

   a) Produces blunt ends
   b) Cuts DNA at specific sequences
   c) Adds nucleotides to DNA
   d) Ligates DNA fragments
   Answer: b) Cuts DNA at specific sequences

4. Which type of DNA molecule carries genes for antibiotic resistance and fertility?

   a) Chromosomal DNA
   b) Circular DNA
   c) Linear DNA
   d) Mitochondrial DNA
   Answer: b) Circular DNA

5. What is the purpose of inserting a gene of interest into a plasmid with antibiotic resistance genes?

   a) To increase gene expression
   b) To separate out colonies of bacteria
   c) To study gene regulation
   d) To inhibit bacterial growth
   Answer: b) To separate out colonies of bacteria