Question

The term nuclein is coined with the name of
(a) Watson
(b) Crick
(c) Friedrich Miescher
(d) Johanson

Answer 1

The term nuclein is coined with the name of Friedrich Miescher. . Therefore, Option C is the correct answer.

Explanation:

The term used by Friedrich Miescher to describe the nuclear material he discovered in 1869, which today is known as DNA.

Miescher isolated various phosphate-rich chemicals, which he called nuclein (now nucleic acids), from the nuclei of white blood cells in 1869 in Felix Hoppe-Seyler's laboratory at the University of Tübingen, Germany, paving the way for the identification of DNA as the carrier of inheritance.  

Answer 2

Answer:

(c) Friedrich Miescher

Explanation:

• Miescher paved the way for various phosphate-containing chemicals, which he isolated Nuclein (now called nucleic acids), from the nuclei of white blood cells in 1869 in the laboratory of Felix Hope Seyler at the University of Tübingen, Germany, as carriers of inheritance DNA identification.
• The significance of the discovery, first published in 1871, was not clear at first, and Albrecht Kossel made initial inquiries into its chemical structure.
• Later, Friedrich Mischer took up the idea that nucleic acids may be involved in heredity  and even stated that there might be something similar to an alphabet that could explain the variation. How does it arise.
• In the summer of 1865, Friedrich worked for organic chemist Adolf Stecker in Göttingen, but his studies were interrupted for the year when he became ill with typhoid fever, which left him hearing impaired. However, he still obtained his MD in 1868.
• Mischer realized that his partial deafness would be a disadvantage as a doctor, so he turned to physical chemistry. He originally wanted to study lymphocytes, but was encouraged by Felix Hope-Seiler to study neutrophils.
• He was interested in studying the chemistry of the nucleus. It was difficult to obtain sufficient numbers of lymphocytes for study, while neutrophils were known to be the main and one of the first components in pus and could be obtained from bandages at a nearby hospital. The problem, however, was washing the cells from the bandages without damaging them.
• Mischer prepared various salt solutions, eventually producing one with sodium sulfate. The cells were filtered. Since centrifuges were not available at that time, the cells were allowed to settle at the bottom of a beaker. Then he tried to separate the free nucleus from the cytoplasm.
• He subjected the purified nucleus to an alkaline extraction, followed by acidification, resulting in the formation of a precipitate that Mischer called nuclein (now known as DNA). They found that it contains phosphorus and nitrogen, but not sulphur.
• The discovery was so different from anything at the time that Hope-Sealer himself repeated all of Mischer's research before publishing it in his journal. Mischer then studied physiology in Leipzig in Karl Ludwig's laboratory for a year before being appointed professor of physiology.
• Analyzing the structure of salmon sperm, Mischer also discovered the alkaline substance protamine; This discovery was published in 1874. It was later used as protamine sulfate in the stabilization of insulin (NPH insulin) and as a reversal agent for the anticoagulant drug heparin.