Next part Flashcards
(20 cards)
Sticky ends
- Exposed staggered ends of
bases - palindromic base sequences
- created by restriction
endonuclease enzymes
Palindromic
sequence
sequences of bases that read
the same forwards as they do
backwards
Blunt end
When a restriction
endonuclease cuts the DNA
double-strand in the same
position
there is no overhang of bases
What are the two
methods to amplify
DNA fragments?
In vivo cloning
in vitro cloning (PCR)
Promoter region
a sequence of DNA bases that
are the binding site for RNA
polymerase to enable
transcription of that gene to
occur
Terminator
region
sequence of DNA bases added
at the end of the gene
it causes RNA polymerase to
detach and stop transcription
to ensure one gene is copied
into mRNA at a time
Plasmid
a small loop of bacterial DNA
contains only a few genes
contains the genes for
antibiotic resistance
Recombiant plasmid
- a small loop of bacterial DNA with the DNA from another organism inserted into it
Transformation
the process of getting a plasmid
to re-enter a bacterium
involves calcium ions and
temperature shocking
How can
transformed cells
be identified?
using marker genes
antibiotic resistance genes
genes coding for fluorescent
proteins
genes coding for enzymes
What is a
marker gene?
A gene inserted into a plasmid
to help identify bacteria that
have taken up the recombinant
DNA (e.g. antibiotic resistance
or fluorescence).
DNA
hybridisation
DNA is heated to separate the
double helix into single strands
it is then mixed with
complementary sequences of
single-stranded DNA
it is then cooled so
complementary strands will
anneal (form hydrogen bonds)
DNA probe
short, single-stranded pieces of
DNA
labelled radioactively or
fluorescently so that they can
be identified
made to be complementary in
sequenc to gene of interest
Personalised
medicine
screening for the presence of
particular alleles
to select medicines and
personalise health advice based
on your genotype
How can DNA
samples be
collected?
From blood, body cells or hair
follicles
VNTRs
variable number tandem
repeats sequences of bases in
introns
the probability of two
individuals having the same
VNTRs is very low.
How is DNA
extracted from cells
so that it can be
examined?
cell fractionation and
ultracentrifugation
How is DNA
digested in genetic
fingerprinting?
Restriction endonucleases are
added to cut the DNA into
smaller fragments
enzymes that cut close to the
target VNTRs are added
Why can the genome not
be easily translated into
the proteome in complex
organisms?
due to the presence of non-
coding DNA and regulatory
genes
What is the role of
DNA ligase in
making
recombinant DNA?
used to stick the DNA fragment
to create recombinant DNA
