Biology Questions and Answers
- What are DNA ligases? How
do these enzymes participate
in the recombinant DNA
technology?
DNA ligases are enzymes specialized intying the complementary DNA chains
that form thenzymes are used in the recombie DNA double helix. Tnanthese
DNA technology to insert pieces of DNA
cut by restrictionDNA molecules su enzymes into othbmitted to the actioner (^)
of the same endonucleases.
- What are plasmids?
Plasmids are circular DNA molecules
present in the genetic material of bacteria. They may contain genes some
responsible fsome antibioticsor bacterial and for proteins that resistance to (^)
cause virulence (pathogenic hostility).
- How is genetic engineering
used to create bacteria
capable of producing human
insulin?
In the production obacteria the human insulin f human insulin gene is by
incorporated into the genetic material othese microorganisms. The mutant f
bacteria multiply forming lineages of
insulin-producing bacteria.
In bacteria there are circular strands of
DNA callewhich act as an accessoryd plasmids, minichr to the mainomosomes
DNA. To create a mutant bacteria
capable of producing submitted to the action insulin of restrictiona plasmid is
enzymes (restriction endonucleases)specialized iThe once circularn cutting plasmid is oDNA fragments.pen by the (^)
restriction enzyme. The same enzyme is
used to cut a hcontaining the insulin guman DNA molecene. The piece ofule (^)
human DNA containing the insulin gene
then has itsplasmid with th extremities boe help of DNA und to theligases. (^)
The recombinant plasmid containing the
human insulin gthe bacteria. ene is then inserted into
Another human hormone alreadyproduced by recombinant bacteria (^) is GH
(somatotropin, or growth hormone).
The insertion of DNA molecules into
cells of an individof the gene therapy, ual is also the methoda promising
treatment for genetic diseases. In gene
therapy cells from an organism din the production of a given proteineficient
receive (by means of vectors, e.g.,
virus) pieces of DNA protein gene and they then begin tocontaining the (^)
synthesize the protein.
- What is cloning?
Cloning is the making genetically identical to anotof an organismher by
means of genetic engineering.
The basis of cloning transplantation technology. A is the nucleusnucleus (^)
from a can embryonic (not differentiated) cellell is extracted, generally from
and this nucleus is inserted into a
previously enucleated reproductive cell(in general an egg cell); the egg is then (^)
implanted in the organ where the
embryonic development will take place.If embryonic development occurs the
new organism will have identical genetic
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