Explain the basis on which he arrived at this conclusion.
He proposed that if 20 amino acids are to be coded by 4 bases, then the code should be made up of three nucleotides. 43 = 64, if it was 2 codon then 42 = 16 which is less than 20 and a 4 codon would give 256 amino acids which is much more than required. So, the codon was proposed to be triplet.
Write the types of sex-determination mechanisms the following crosses show. Give an example of each type
(i) Female XX with Male XO
Name the scientist who suggested that the genetic code should be made of a combination of three nucleotides.
State how Agrobacterium tumifaciens has been made a useful cloning vector to transfer DNA to plant cells.
Write the types of sex-determination mechanisms the following crosses show. Give an example of each type
(ii) Female ZW with Male ZZ
Apart from being a part of the food chain, predators play other important roles. Mention any two such roles supported by examples.
