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What four general characteristics must the genetic material possess?

How does an RNA nucleotide differ from a DNA nucleotide?

Match the researchers (a-j) with the discoveries listed. a. Kossel b. Fraenkel-Conrat c. Watson and Crick d. Levene e. Miescher f. Hershey and Chase g. Avery, MacLeod, and McCarty h. Griffith i. Franklin and Wilkins j. Chargaff ______Took X-ray diffraction pictures used in constructing the structure of DNA. _______Determined that DNA contains nitrogenous bases. ________Identified DNA as the genetic material in bacteriophages. _________Discovered regularity in the ratios of different bases in DNA. __________Determined that DNA is responsible for transformation in bacteria. _________Worked out the helical structure of DNA by building models. _________Discovered that DNA consists of repeating nucleotides. _________ Determined that DNA is acidic and high in phosphorus. _________ Conducted experiments showing that RNA can serve as the genetic material in some viruses. _______Demonstrated that heat-killed material from bacteria can genetically transform live bacteria.

Each nucleotide pair of a DNA double helix weighs about \(1 \times\) \(10^{-21} \mathrm{~g}\). The human body contains approximately \(0.5 \mathrm{~g}\) of DNA. How many nucleotide pairs of DNA are in the human body? If you assume that all the DNA in human cells is in the B-DNA form, how far would the DNA reach if stretched end to end?

A B-DNA molecule has 1 million nucleotide pairs. How many complete turns of the helix are there in this molecule?