enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Biological roles of the elements - Wikipedia

    en.wikipedia.org/wiki/Biological_roles_of_the...

    Four of these elements (hydrogen, carbon, nitrogen, and oxygen) are essential to every living thing and collectively make up 99% of the mass of protoplasm. [1] Phosphorus and sulfur are also common essential elements, essential to the structure of nucleic acids and amino acids, respectively.

  3. Hershey–Chase experiment - Wikipedia

    en.wikipedia.org/wiki/Hershey–Chase_experiment

    Radioactive sulfur-35 was used to label the protein sections of the T2 phage, because sulfur is contained in protein but not DNA. [ 6 ] Hershey and Chase inserted the radioactive elements in the bacteriophages by adding the isotopes to separate media within which bacteria were allowed to grow for 4 hours before bacteriophage introduction.

  4. DNA - Wikipedia

    en.wikipedia.org/wiki/DNA

    The structure was reported in a letter titled "MOLECULAR STRUCTURE OF NUCLEIC ACIDS A Structure for Deoxyribose Nucleic Acid ", in which they said, "It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material."

  5. Nucleic acid - Wikipedia

    en.wikipedia.org/wiki/Nucleic_acid

    Nucleic acids RNA (left) and DNA (right). Nucleic acids are large biomolecules that are crucial in all cells and viruses. [1] They are composed of nucleotides, which are the monomer components: a 5-carbon sugar, a phosphate group and a nitrogenous base. The two main classes of nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid ...

  6. Nucleic acid structure determination - Wikipedia

    en.wikipedia.org/wiki/Nucleic_acid_structure...

    Nucleic acids have a smaller percentage of hydrogen atoms, which are the atoms usually observed in NMR, and because nucleic acid double helices are stiff and roughly linear, they do not fold back on themselves to give "long-range" correlations. [3] The types of NMR usually done with nucleic acids are 1 H or proton NMR, 13 C NMR, 15 N NMR, and ...

  7. Nucleotide - Wikipedia

    en.wikipedia.org/wiki/Nucleotide

    This nucleotide contains the five-carbon sugar deoxyribose (at center), a nucleobase called adenine (upper right), and one phosphate group (left). The deoxyribose sugar joined only to the nitrogenous base forms a Deoxyribonucleoside called deoxyadenosine, whereas the whole structure along with the phosphate group is a nucleotide, a constituent of DNA with the name deoxyadenosine monophosphate.

  8. Nucleic acid quantitation - Wikipedia

    en.wikipedia.org/wiki/Nucleic_acid_quantitation

    Contamination by phenol, which is commonly used in nucleic acid purification, can significantly throw off quantification estimates. Phenol absorbs with a peak at 270 nm and a A 260/280 of 1.2. Nucleic acid preparations uncontaminated by phenol should have a A 260/280 of around 2. [2]

  9. Nuclear magnetic resonance spectroscopy of nucleic acids

    en.wikipedia.org/wiki/Nuclear_magnetic_resonance...

    19 F NMR is also useful if nonnatural nucleotides such as 2'-fluoro-2'-deoxyadenosine are incorporated into the nucleic acid strand, as natural nucleic acids do not contain any fluorine atoms. [2] [4] 1 H and 31 P have near 100% natural abundance, while 13 C and 15 N have low natural abundances. For these latter two nuclei, there is the ...