Nucleotides are joined together by:
To solve the problem, we need to determine how nucleotides are joined together in a biological context.
1. Understanding Nucleotides:
Nucleotides are the building blocks of nucleic acids, such as DNA and RNA. Each nucleotide consists of a sugar molecule, a phosphate group, and a nitrogenous base.
2. Identifying the Bond:
In nucleic acids, nucleotides are linked to form a polynucleotide chain. The bond that joins nucleotides is formed between the phosphate group of one nucleotide and the sugar (specifically, the 3’ hydroxyl group) of the adjacent nucleotide. This bond is called a phosphodiester bond, which creates the sugar-phosphate backbone of DNA or RNA.
3. Confirming the Specificity:
The phosphodiester bond is specific to the covalent linkage between nucleotides in nucleic acids. Other types of bonds (e.g., hydrogen bonds) are involved in base pairing between strands, but the question focuses on joining nucleotides within a single strand.
Final Answer:
Nucleotides are joined together by phosphodiester bonds.
Write IUPAC names of the following compounds and classify them into primary, secondary and tertiary amines.
(i) (CH3 )2CHNH2 (ii) CH3 (CH2 )2NH2 (iii) CH3NHCH(CH3 )2
(iv) (CH3 )3CNH2 (v) C6H5NHCH3 (vi) (CH3CH2 )2NCH3 (vii) m–BrC6H4NH2
Give one chemical test to distinguish between the following pairs of compounds.
(i) Methylamine and dimethylamine
(ii) Secondary and tertiary amines
(iii) Ethylamine and aniline
(iv) Aniline and benzylamine
(v) Aniline and N-methylaniline
Account for the following:
(i) pKb of aniline is more than that of methylamine.
(ii) Ethylamine is soluble in water whereas aniline is not.
(iii) Methylamine in water reacts with ferric chloride to precipitate hydrated ferric oxide.
(iv) Although amino group is o– and p– directing in aromatic electrophilic substitution reactions, aniline on nitration gives a substantial amount of m-nitroaniline.
(v) Aniline does not undergo Friedel-Crafts reaction.
(vi) Diazonium salts of aromatic amines are more stable than those of aliphatic amines. (vii) Gabriel phthalimide synthesis is preferred for synthesising primary amines.