Arrange the steps for transformation of recombinant DNA in sequence -
(A). For heat shock, bacterial cells are placed at 42°C; and then they are placed on ice.
(B). The bacterial cells must be made 'competent' to take up DNA by treating them with a specific concentration of divalent cation such as calcium.
(C). The bacteria are now able to take up the recombinant DNA.
(D). Recombinant DNA can then be forced into those cells by incubating the cells with recombinant DNA on ice.
Choose the correct answer from the options given below:(C)
(C), (B), (D), (A)

Which of the following hormone is generally not produced by the placenta?

Heroin, commonly called as smack is a/an:

Bioactive molecule, cyclosporin A, that is used as an immunosuppressive agent in organ-transplant patients, is produced by the fungus -

The initial idea of triplet nature of codon was proposed by:

Which one of the followings is responsible for producing the large holes in "Swiss cheese"?

Which one of the following statements is incorrect about ecological pyramids?

How much energy will be converted by the primary producer to net primary productivity from 20,000 J of available sunlight energy?

If \(x\) is real, the minimum value of \(x^2-8 x+20\) is :

If \(f(x)=\left\{\begin{array}{ll}\frac{\tan \left(\frac{\pi}{4}-x\right)}{\cot 2 x}, & x \neq \frac{\pi}{4} \\ K, & x=\frac{\pi}{4}\end{array}\right.\) is continuous at \(x=\frac{\pi}{4}\), then the value of \(K\) is :

If the line \(\frac{-x+1}{3}=\frac{-y-2}{-2 k}=\frac{z+3}{2}\) and \(\frac{-1+x}{3 k}=\frac{-1+y}{1}=\frac{-z+6}{5}\) are perpendicular, then the value of \(k\) is :

Read the passage carefully and answer the Questions
Werner in 1898, propounded his theory of coordination compounds. In coordination compounds metals show two types of linkages (valences)-primary and secondary. The primary valences are normally ionisable and are satisfied by negative ions. The secondary valences are non-ionisable. These are satisfied by neutral molecules or negative ions. The secondary valence is equal to the coordination number and is fixed for a metal. The ions or group bound by the secondary linkages to the metal have characteristic spatial arrangements corresponding to the different coordination numbers. Both double salts as well as complexes are formed by the combination of two or more stable compounds in stoichiometric ratio. However, they differ in the fact that double salts such as carnallite, Mohr's salt, potash alum etc. dissociate into simple ions completely when dissolved in water. But complex ions do not dissociate completely into simple ions.
When \(1 mol CrCl _3 \cdot 6 H _2 O\) is treated with excess of \(AgNO _3, 3 mol\) of AgCl are obtained. The formula of the complex is:

\(\text{C-Cl}\) bond in chlorobenzene in comparison to \(\text{C-Cl}\) bond in methyl chloride is :