Question : The following pictures show two personalities which biologists will not forget.a. Who are they? How did the world honour them for making this contribution? c . Briefly give details of their contribution to biology.

Question : The following pictures show two personalities which biologi

1.	Question : The following pictures show two personalities which biologists will not forget.a. Who are they? How did the world honour them for making this contribution? c . Briefly give details of their contribution to biology.
Answer» Solution :a. A. Watson and B. Crick b. By giving NOBEL Prize c. James Watson and Francis Crick proposed the double helical structuremodel of DNA. According to them, the DNA is formed of two polynucleotide chains. The two chains are spirally coiled together to form a double helix, The two chains are formed by sugar and phosphate and are connected by nitrogen bases. The BASE pair is always Adenine with Thymine (A = T) and Cytosine with Guanine (C=G). Thus the DNA molecule looks like a spiral staircase with sugar and phosphate units along the RAILING and the hydro gen BONDED base-pairs as the steps. For this outstanding discovery thescience world honoured them by giving Nobel Prize.