chapter 20 Flashcards
What is genetic engineering?
Direct manipulation of genes for practical purposes
How is genetic engineering done?
DNA sequencing, gene cloning, gene therapy, etc.
What is DNA sequencing?
A scientific process by which a specific strand of each fragment is immobilized, and the complementary strand synthesized one nucleotide at a time
How is DNA sequencing done?
A specific strand of each fragment is immobilized, and the complementary strand synthesized one nucleotide at a time; Thousands or hundreds of thousands of fragments about 300 nucleotides long can be sequenced in parallel
Describe how restriction enzymes are used to cut DNA molecules.
Restriction enzymes are used to cut the sugar-phosphate backbone of DNA in order to make a recombinant DNA fragment
What are restriction fragments?
Fragments of DNA made during the cutting process
How can restriction fragments be inserted into strands for foreign DNA?
Sticky ends can bond with complementary sticky ends of other fragments; DNA ligase is an enzyme that seals the bonds between restriction fragments which allows researchers to join two DNA fragments from different sources
Where are the DNA molecules cut?
Restriction sites
What is organismal cloning?
A process that produces one or more organisms genetically identical to the “parent” that donated the single cell
How is nuclear transplantation accomplished?
The nucleus of an unfertilized egg cell or zygote is replaced with the nucleus of a differentiated cell
Will cloned animals always look and behave the same as the original organism?
no
What are stem cells?
A relatively unspecialized cell that can reproduce itself indefinitely, or under certain conditions can differentiate into one or more types of specialized cells
Totipotent
a cell that can generate an entire new organism and is used for cloning in plants
Pluripotent
a cell that can differentiate into many different cell types
embryonic stem cell
cells in embryos that are capable of giving rise to differentiated embryonic cells of any type
