Moleculaire genetica
16.1
In 1953, James Watson and Francis Crick introduced an elegant double-helical
model for the structure of deoxyribonucleic acid (DNA); Hereditary information is
encoded in DNA and reproduced in all cells of the body. This DNA program directs the
development of biochemical, anatomical, physiological, and (to some extent)
behavioral traits. DNA is copied during DNA replication, and cells can repair their
DNA
Evidence That DNA Can Transform Bacteria
Griffith worked with two strains of a bacterium, one pathogenic and one harmless.
When he mixed heat-killed remains of the pathogenic strain with living cells of the
harmless strain, some living cells became pathogenic. He called this phenomenon
transformation, now defined as a change in genotype and phenotype due to
assimilation of foreign DNA. Zie Figuur 1
Figuur 1
Evidence That Viral DNA Can Program Cells
More evidence for DNA as the genetic material came from studies of viruses that
infect bacteria. Such viruses, called bacteriophages (or phages), are widely used in
molecular genetics research. A virus is DNA (sometimes RNA) enclosed by a
protective coat, often simply protein.
In 1952, Alfred Hershey and Martha Chase performed experiments showing that DNA
is the genetic material of a phage known as T2. To determine the source of genetic
material in the phage, they designed an experiment showing that only one of the two
1
16.1
In 1953, James Watson and Francis Crick introduced an elegant double-helical
model for the structure of deoxyribonucleic acid (DNA); Hereditary information is
encoded in DNA and reproduced in all cells of the body. This DNA program directs the
development of biochemical, anatomical, physiological, and (to some extent)
behavioral traits. DNA is copied during DNA replication, and cells can repair their
DNA
Evidence That DNA Can Transform Bacteria
Griffith worked with two strains of a bacterium, one pathogenic and one harmless.
When he mixed heat-killed remains of the pathogenic strain with living cells of the
harmless strain, some living cells became pathogenic. He called this phenomenon
transformation, now defined as a change in genotype and phenotype due to
assimilation of foreign DNA. Zie Figuur 1
Figuur 1
Evidence That Viral DNA Can Program Cells
More evidence for DNA as the genetic material came from studies of viruses that
infect bacteria. Such viruses, called bacteriophages (or phages), are widely used in
molecular genetics research. A virus is DNA (sometimes RNA) enclosed by a
protective coat, often simply protein.
In 1952, Alfred Hershey and Martha Chase performed experiments showing that DNA
is the genetic material of a phage known as T2. To determine the source of genetic
material in the phage, they designed an experiment showing that only one of the two
1
