$A$ sequence of how many nucleotides in messenger $RNA$ makes a codon for an amino acid?

The correct order of increasing $s-$character (in percentage) in the hybrid orbitals of the following molecules/ions is:
$(I)$ $CO_3^{2-}$ $(II)$ $XeF_4$ $(III)$ $I_3^-$ $(IV)$ $NCl_3$ $(V)$ $BeCl_2$

In the circuit shown in the figure,neglecting source resistance,the voltmeter and ammeter readings will respectively be:

What do mast cells secrete?

Which of the following substances combines with hemoglobin in the blood to form carboxyhemoglobin?

The function $f(x) = \log(1 + x) - \frac{2x}{2 + x}$ is increasing on