- Explain the structure of DNA – use the terms nucleotides, antiparallel, strands, and complementary base pairing.
DNA is made up of sugars, phosphates, and nitrogen. The sugars and phosphates create the two backbones made of sugar-phosphates and nucleotides. The bases of the nucleotides are inside the ladder shape. The two strands of DNA are antiparallel as they are read in opposite directions. Certain bases attract each other and create what is called complementary base pairing. There are four bases Adenine, Thymine, Guanine, and Cytosine. The two pieces of DNA are kept together by hydrogen bonds in the middle of the nucleic acid. DNA is replicated by being split into two by a helicase and then the two strands are paired with different strands through complementary base pairing. This process is called DNA polymerase. The result is two identical DNA strands. This is the only process for how DNA is able to replicate.
2. This activity really explained DNA replication and how it can twist into a double helix, also it was a lot easier to build in in 3D then to see it on an image. To improve the project I think that we should use mini marshmallows to represent the complementary base pairing and twizzlers or some long piece of candy to form the two backbones. But the watermelon gummy and the two bigfoot gummies did a great job representing DNA polymerase and the unzipping of DNA.
The DNA twisted into a double helix
The unzipping of DNA with the watermelon showing the DNA helicase
The strands are now separated and the big blue foot candy shows the DNA polymerase that find different strands for complementary base pairing
The end product is two identical strands of DNA