Streptococcus pneumoniae smooth colonies

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Streptococcus pneumoniae - smooth colonies
Geneticists identify mutant organisms by
recognizing observable traits different in the
mutant than in wild type. Smooth streptococcus
are infectious while rough colonies are
not. http//www.saudetotal.com/microbiologia/colc
ocos.htm
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Geneticists identify mutant organisms by
recognizing observable traits different in the
mutant than in wild type. Some bacteria mutate
at a higher frequency than normal.
wild type bacteria low mutation frequency
mutator bacteria high mutation rate
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Identification of the mutS and mutL genes
Identification of human homologs of mutS and
mutL genes
Hereditary nonpolyposis colon cancer (HNPCC)
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Geneticists identify mutant organisms by
recognizing observable traits different in the
mutant than in wild type. Mendel studied the
genetic differences observable in
peas. http//hcs.osu.edu/hcs200/ BreeQZ.html
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Geneticists identify mutant organisms by
recognizing observable traits different in the
mutant than in wild type. Morgan studied the
phenotypic differences in flies. http//www.ucl.a
c.uk/ucbhjow/ bmsi/bmsi_8.html
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Geneticists identify mutant organisms by
recognizing observable traits different in the
mutant than in wild type. Some flies have red
eyes while some have white eyes. Borukhov S, Lee
J, Laptenko O. Mol Microbiol. 2005
Mar55(5)1315-24.
Red eye
White eye
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Geneticists identify mutant organisms by
recognizing observable traits different in the
mutant than in wild type. Some flies have
differences in developmental genes. http//www.mo
lbio.princeton.edu/.../ projects/03/development.ht
ml
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A bacteriophage is a virus that infects bacteria.
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This is an electron microscope image of a
bacteriophage. www.agen.ufl.edu/chyn/age2062/
lect/lect_06/lect_06.htm
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When bacteriophages bind to their host, the virus
injects its DNA into the bacteria. http//www.cel
lsalive.com/phage.htm phagedna.gif
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The viral DNA is incorporated into the host
genome and the host is programmed to produce many
more virus particles. The host cell eventually
bursts under the strain of virus production and
releases the new bacteriophage particles. http//
www.cellsalive.com/phage.htm tphage2.gif