chapter 20

What are the two basic purposes of gene cloning?

To make copies of or amplify a particular gene and to produce a protein product.

What is a cloning vector?

A DNA molecule used to carry foreign DNA into a host cell for replication and expression.

What are key features of cloning vectors?

Origin of replication, selectable marker genes, multiple cloning site, size, and stability.

What is recombinant DNA (rDNA)?

DNA formed by joining genetic material from two different sources to create a new combination of genes.

What are the steps to create recombinant DNA?

Isolation of DNA, cutting DNA with restriction enzymes, ligation, transformation, and selection and screening.

PCR

Polymerase Chain Reaction

What is the function of Taq DNA polymerase in PCR?

Taq DNA polymerase is a heat-stable enzyme used to amplify specific target segments of DNA during PCR.

PCR uses a pair of ________ specific for the sequence to be amplified

primers

PCR amplification occasionally

incorporates errors into the amplified strands and so cannot substitute for gene cloning in cells

What characterizes totipotent cells in plants?

Totipotent cells can generate a complete new organism and can give rise to all specialized cell types.

What are stem cells?

Relatively unspecialized cells that can reproduce indefinitely and differentiate into specialized cell types under certain conditions.

What are induced pluripotent stem cells (iPSCs)?

Specialized cells that have been genetically reprogrammed to behave like embryonic stem cells, allowing them to differentiate into almost any cell type.

what are iPSCs generated by

taking somatic cells and introducing specific genes that reprogram them into a pluripotent state

What are the advantages of using iPSCs?

Avoid ethical concerns of embryonic stem cells and potential for personalized medicine to reduce immune rejection.

What is gene therapy?

The introduction of genes into an afflicted individual for therapeutic purposes, particularly effective for disorders traceable to a single defective gene.

What ethical questions are raised by gene therapy and gene editing?

Concerns about the morality of tampering with human genes and the implications of genetically modifying humans.

Jennifer Doudna

co-discoverer of CRISPR-Cas9, recognized not only its potential but also the danger of its misapplication