A Science Odyssey You Try It: DNA Workshop Title

DNA Replication (text version)

screen shot of DNA Workshop activity

Unzip DNA

Help Window:
The first step of replication is "unzipping" the DNA molecule. This will divide the molecule lengthwise.

Select Unzip to divide the molecule.

Selecting the "Unzip" button causes the DNA molecule to split lengthwise.

What Happened Window:
In a real cell, the molecule unwinds from spools made of protein, then untwists. (Here the molecule is already unwound and untwisted.) The DNA now resembles a ladder. Enzymes, special kinds of proteins, move up the ladder, breaking the rungs.

Match bases to make new DNA strand

Drag and drop from well:

Help Window:
DNA is made up of four types of bases: adenine (A), cytosine (C), guanine (G), and thymine (T). Each base has a complement -- another base that it can connect to. A complements T, and C complements G.

Drag bases from the left to their complementary bases on the DNA strands. Don't worry about the orientation of a base -- it will automatically flip, if it needs to, as it approaches the DNA strand.

Nucleotides are dragged from one area of the screen to the separated DNA strands.

What Happened Window
Well done. Replication is complete.

Our new DNA molecules consist of only a few base pairs. Not so with real DNA.

Each human chromosome, for example, contains millions of base pairs. All 46 human chromosomes contain 3 billion pairs.

If you haven't already done so, check out Protein Synthesis.

DNA Replication

All Wound Up

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