Dna replication is called semiconservative because of what?

during replication the parent strand remains the same whereas the daughter strand is a new strand.this is semiconservative

Because in the beginning, there were three ideas for how DNA replication could occur.

A parent strand could create a daughter strand. The parent strand would remain the same after replication, whilst the daughter strand would be all new DNA. This is Conservative.

A parent strand could somehow break up and form together with new daughter pieces, in a 50/50 split with parent DNA and daughter DNA mixed together throughout the strands. This is Dispersive.

The intermediate is the one that actually happens, where a parent strand is used to make a daughter strand, and these hook together to make DNA. So if you started with 1 parent DNA, you will end up with two parent/daughter hybrids, as DNA is a double helix. This is semi-conservative, as you conserve a helix of the parent DNA, but you don't keep them together.

Hope this helped!

Because the new DNA has two strand. One of the strand was called "old" because it came from the previous DNA helix and didn't change. It is called "template strand". The other strand of DNA was newly created and was called "composed strand". Because of those, DNA is called "semi-conservative".
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