Advertisements
Advertisements
प्रश्न
Give scientific reasons:
α-Amino acids have high melting points compared to the corresponding amines or carboxylic acids of comparable molecular mass.
Why α-amino acids have high melting points compared to the corresponding amines or carboxylic acids of comparable molecular mass?
Advertisements
उत्तर
- This is due to the peculiar structure called zwitter ion structure of α -amino acids.
- α-Amino acid molecule contains both acidic carboxyl (–COOH) group as well as basic amino (–NH2) group.
- Proton transfer from the acidic group to the basic group of amino acid forms a salt, which is a dipolar ion called zwitter ion.
Thus, α-amino acids have high melting points compared to the corresponding amines or carboxylic acids of comparable molecular mass.
संबंधित प्रश्न
Select the most correct choice.
A disulphide link gives rise to the following structure of a protein.
Write the names and schematic representations of all the possible dipeptides formed from alanine, glycine and tyrosine.
Draw a neat diagram for the following:
Zwitter ion
Draw a neat diagram for the following:
Secondary structure of protein
Draw a neat diagram for the following:
Enzyme catalysis
The optically inactive α-amino acid among the following is _____________
In the process of denaturation, there is NO change in the structure following protein.
Complete the following reaction.
\[\ce{H2N - CH2 - COOH + H2N - CH2 - CH2 - COOH ->[-H2O] ?}\]
Define peptide bond.
Write types of proteins depending upon molecular shape.
Explain globular and fibrous proteins with example.
Draw the structure of Haworth formula of sucrose.
Explain the primary structure of proteins.
From the following identify the INCORRECT match with respect to the different structures of proteins.
____________ is NOT a simple protein.
Nucleotide differs from a nucleoside as it has ______
Pyrimidines are ______.
Purine and pyrimidine bases are placed regularly along the DNA molecules at a distance of ______
Read the following statements and select the correct option.
- In quaternary structure, the peptide chains are much looped, twisted, and folded back on themselves due to formation of hydrogen bonds.
- When a protein has more than two polypeptide subunits their arrangement in space is called secondary structure.
Identify 'P' and 'Q' in the following table.
| Proteins | Role |
| immunoglobulin | P |
| Q | Blood clotting |
Choose the WRONG statement from the following.
Identify (i) and (ii) and select the correct option.
i. Protein portion of the enzyme is called the ____________.
ii. Non-protein constituent binding to the enzyme is called as the ____________.
Which of the following contains keratin?
The conjugate acid of \[\ce{CO^2-_3}\] is ____________.
Identify the enzyme X in the following reaction.
\[\ce{H2O2(aq) ->[x] H2O(l) + \frac{1}{2} O2(g)}\]
Complete the analogy and select the correct option.
α-helix structure : Keratin :: β-pleated sheet : ____________.
Which among the following amino acids has lowest molar mass?
The side chain R in cysteine is ____________.
Which of the following is not a broad spectrum antibiotics?
Which of the following is the simplest amino acid?
The basic amino acid is ____________.
The molecular weight of hemoglobin is ______ Daltons.
The number of proteins in an average human cell is over ______.
The most abundant cellular protein is ______.
A protein is a sequence of amino acids. The end of the polypeptide chain of -NH2 end and at -COOH end are respectively called ______.
An iron-containing red protein is ______
Which of the following amino acids has –CH2OH group in its side chain?
Which among the following is basic amino acid?
The central dogma of molecular genetics states that the genetic information flows from:
In a protein, various amino acids linked together by ____________.
In aqueous solution of amino acids mostly exists in, ____________.
Among the following L-serine is:
The secondary structure of a protein refers to ____________.
Which of the following statement is not correct?
Give the differences between the primary and secondary structure of proteins.
Write a short note on peptide bond.
Write the structure of all possible dipeptides which can be obtained from glycine and alanine.
The amino acid, which is basic in nature is ______.
Which among the following enzymes hydrolysis starch?
Tertiary structure of protein is stabilised by ______.
The tightly bound non-proteinaceous organic compound in enzyme is ______.
Write a short note on peptide bond.
Write a short note on peptide bond.
Write a short note on peptide bond.
Write the Zwitter ion structure of alanine.
Write a short note on peptide bond.
Write a short note on peptide bond.
Write the Zwitter ion structure of alanine.
Write the Zwitter ion structure of alanine.
Write a short note on peptide bond.
Write a short note on peptide bond.
Short Answer Question.
Write the Zwitter ion structure of alanine.
Write the Zwitter ion structure of alanine.
Write a short note on peptide bond.
Write the Zwitter ion structure of alanine.
The number of amino groups in the amino acids present in amides is ______.
