Hello my penfriend! I remember You asked me to describe my school. It is a very large green house. There are 3 floors. There are a lot of classrooms. There is a swimming pool, I like it veru much! There is a school museum in our school, it's a pride of my school.
The nucleic acid composition of the nucleic acids DNA RNA Isolation The macromolecular structure of DNA deoxyribonucleic acid Isolation of RNA Nature internucleotide linkages DNA RNA nucleic acids, meaning References 1.Sostav Nucleic Acids Nucleic acids are macromolecules composed of biopolimery.Ih than once repeating units which are represented by nucleotides. And their logical called polynucleotides. One of the main characteristics of the nucleic acids is their nucleotide composition . The composition of nucleotides ( structural unit of nucleic acids) consists of three components : a nitrogenous base . Perhaps pyrimidine and purine . In nucleic acids contained base 4 different types : two of them belong to the class of two purine - pyrimidine to the class . Nitrogen contained in the rings , gives the basic properties of molecules . phosphoric acid residue . Nucleic acids are acids because their molecules contain phosphoric acid. monosaccharide - ribose or 2- deoxyribose . Sugars, which is part of the nucleotide contains five carbon atoms , i.e. represents a pentose . Depending on the kind of pentoses present in the nucleotide are two types of nucleic acid - ribonucleic acid (RNA ) which contain ribose, and deoxyribonucleic acid ( DNA) containing dizoksiribozu . Nucleotide is basically a phosphate ester of the nucleoside. The structure consists of two nucleoside component monosaccharides ( ribose or deoxyribose ) and a nitrogenous base . At sunset the 40 's - early 50's , when it began to appear such research methods as paper chromatography and UV spectroscopy . Numerous studies have confirmed the nucleotide compositionNC ( Chargaff , ANBelozersky ) . Data obtained at the end of the research destroyed obsolete and incompetent representation of nucleic acids , as polymers containing repeating tetranucleotide sequences - tetranucleotide theory of the PC dominated the 30 - 40s . Also gave grounds for the creation of modern ideas not only on the primary structure of DNA and RNA , but also about their macromolecular structure and function .
1) Напиши числа: 948 - nine hundred and fourty eight 1723 - one thousand seven hundred and twenty three или если это год, то seventeen twenty three 591 - five hundred and ninety one 2) Задай вопросы: My friend had a headache in the evening yesterday, didn't he? Did my friend had a headache in the evening yesterday? Who had a headache in the evening yesterday? When did my friend had a headache in the evening yesterday? Did my friend had a headache or teethache in the evening yesterday?
3) Найди правильный ответ: 1. Long ago men … different types of communication. a) had used 2. The electric telegraph … by A.G. Bell. a) was invented 3. I … in Australia now. b) am living 4. … I spend my summer in the south next year? b) Will 5. He … his homework yesterday. b) did