Semi-conservative hypothesis : verification using chromosome marking
The Meselson and Stahl experiment has shown very simply that replication of DNA is semi-conservative. The following experiment is a confirmation. It uses observations made on marked chromosomes.
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Semi-conservative - Refers to the fact that after the replication of one DNA helix each of the two daughter helices that result contain one newly-synthesized and one pre- existing strand of DNA.

The term proposed by Delbrück and Stent (1957) to describe the method of replication of DNA postulated by Watson and Crick (1953) in which the molecule divides longitudinally, each half (strand) being conserved and acting as a template for the formation of a new half.

Semi-conservative replication the mechanism by which DNA produces identical copies of itself
Sepal the outermost structures of a flower that makes up the calyx.
Septum partition which divides up a larger region into smaller ones ...

the replication of a chromosome is semi-conservative (just as is the replication of a single DNA molecule). That is; the information encoded in each strand of DNA remains intact as it serves as the template for the assembly of a complementary strand.

The parent DNA molecule separates into its two component strands, each of which acts as a template for the formation of a new complementary strand. The two daughter molecules therefore contain half the parent DNA and half new DNA (semi-conservative hypothesis).

DNA Replication (Semi-Conservative Replication)
Transcription: DNA to mRNA
Translation: mRNA to Protein via tRNA ...

DNA replication is semi-conservative as both of the DNA molecules produced are formed from an old strand and a new one. The first stage of DNA replication involves the unwinding of the double strand of DNA (DNA double helix) and separating them by breaking the hydrogen bonds between the bases.

Nucleotide triphosphates (in the forms ATP, GTP, CTP and TTP) are assembled according to the semi-conservative model. Other details of DNA replication are consistent with what we know for prokaryotes.

9) DNA replication is semi-conservative. This means that each strand can separate into single strands and then each of these strands can serve as a template for a new double stranded DNA molecule. This again is possible since A always pairs with T; and C always pairs with G.

synthesis (S), in which the cell duplicates its DNA (via semi-conservative replication).

This is called "semi-conservative" replication since one of the parent strands is "conserved" in the new DNA molecule.

See also: See also: Replication, DNA, Strand, Nucleotide, Molecule


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