Biotechnology: Principles and Processes – Key Concepts

Ten question-and-answer flashcards covering foundational ideas, tools, and processes discussed in the lecture on biotechnology principles and processes.

What two core techniques laid the foundation for modern biotechnology?

Genetic engineering (altering DNA/RNA and introducing it into hosts) and bioprocess engineering (maintaining sterile, large-scale culture conditions to produce biotechnological products).

Why is the origin of replication (ori) an essential feature of a cloning vector?

Ori is the DNA sequence where replication begins, allowing any linked foreign DNA to replicate inside the host and determining how many copies of the insert are produced.

What function do restriction endonucleases serve in recombinant DNA technology?

They act as molecular scissors that recognize specific palindromic sequences in DNA and cut at precise sites, generating defined fragments for cloning.

How do 'sticky ends' produced by restriction enzymes aid in DNA cloning?

Sticky ends are single-stranded overhangs that can hydrogen-bond with complementary ends on other DNA fragments, guiding accurate ligation by DNA ligase.

Which enzyme is responsible for sealing nicks and joining DNA fragments during recombinant DNA construction?

DNA ligase.

What is the purpose of selectable markers on a plasmid vector?

They help identify and eliminate non-transformants by conferring traits (e.g., antibiotic resistance) that allow only cells containing the recombinant plasmid to grow under selective conditions.

What is Polymerase Chain Reaction (PCR) and which enzyme makes it possible at high temperatures?

PCR is an in-vitro technique that exponentially amplifies a specific DNA segment using primers and the thermostable DNA polymerase Taq (from Thermus aquaticus).

Define a bioreactor and state its role in biotechnology.

A bioreactor is a large, controlled vessel that provides optimal conditions (pH, temperature, oxygen, mixing, etc.) for microorganisms or cells to convert raw materials into desired products at industrial scale.

How are bacterial cells rendered 'competent' to take up recombinant DNA?

Cells are treated with divalent cations (e.g., Ca²⁺) and subjected to heat shock, which creates transient pores in the membrane, allowing plasmid DNA to enter.

List the three basic steps involved in genetically modifying an organism.

1) Identify DNA with the desired gene, 2) Introduce that DNA into the host, 3) Ensure maintenance and inheritance of the introduced DNA in the host and its progeny.