What makes up rungs of dna

C bonds to G by three hydrogen bonds. A bonds to T by two hydrogen bonds. A and G are double ringed structures called "purines". C and T are single ringed structures called "pyramidines". Figure 9: Supercoiled eukaryotic DNA. How do scientists visualize DNA?

Figure This karyotype depicts all 23 pairs of chromosomes in a human cell, including the sex-determining X and Y chromosomes that together make up the twenty-third set lower right. Watch this video for a closer look at the relationship between chromosomes and the DNA double helix.

What are karyotypes used for? Who is James Watson? What do we know about Francis Crick? Topic rooms within Genetics Close. No topic rooms are there. Browse Visually. Other Topic Rooms Genetics. Student Voices.

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How can chromosomes be damaged? How does DNA code for proteins? How are chromosomes related to chromatin?