Biomolecules

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The different types of RNA found in the cell are listed below:-

(i) Messenger RNA (m-RNA)

It carries the genetic message code from the DNA to ribosomes. It is produced by the DNA; m-RNA is also single stranded and constitutes about 15% of total RNA.

(ii) Ribosomal RNA (r-RNA)

It is found in

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The structural difference between DNA and RNA are as follows:-

The functional difference between DNA and RNA are as follows:-

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In the helical structure of DNA, the two strands are held together by hydrogen bonds between specific pairs of bases.

Cytosine from hydrogen bond with guanine, while adenine forms hydrogen bond with thymine. As a result, the two strands are complementary to each other.

DNA consists of two strands

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A nucleoside is formed when l-position of a pyrimidine (cytosine, thymine or uracil) or 9- position of a purine (guanine or adenine) base is attached to C-l of sugar (ribose or deoxyribose) by a linkage. Thus in general, nucleosides may be represented as: Sugar-Base.

Nucleoside = sugar + base

On

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Nucleic acids are Biomolecules which are found in the nuclei of all living cells, inform of nucleoproteins or chromosomes (proteins containing nucleic acids as the prosthetic group). Nucleic acids are of two types: – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Nucleic acids are also

14.28 

The deficiency of Vitamin A leads to Xerophthalmia which is hardening of the cornea of the eye and night blindness as well. Vitamin-C is essential to us because its deficiency causes scurvy which is a phenomenon of bleeding gums; and pyorrhoea which is phenomenon of loosening-bleeding of

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Vitamins can be defined as the essential dietary factors required by an organism in minute quantities and whose absence causes specific deficiency Vitamins are broadly classified into two types:-

(i) Fat-soluble vitamins:

These are oily substances not readily soluble in water. These includ

14.26 

During denaturation, 2-degree and 3-degree structures of proteins are destroyed but 1- degree structure remains intact. As a result of denaturation, The globular proteins (soluble in water) are converted into Fibrous proteins (insoluble in water) and their biological activity is lost. Fo

14.25

Enzymes are naturally occurring simple conjugate proteins acting as specific catalysts in all processes. In contrast to ordinary chemical catalyst, it loses activity by pH or temperature change.

For example:- the enzyme used to catalyze the hydrolysis of maltose into glucose is named as maltase.

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Amino acids contain an acidic (carboxyl group) and a basic (amino) group within the same molecule. In aqueous solution, they neutralize each other. The carboxyl group loses a proton while the amino group accepts it. S a result, a dipolar or zwitter-ion is formed.

In zwitter ionic form, the