The human body does not produce

The major product in the following reaction is:

Which amino acids are present in histones?

Four successive members of the first series of the transition metals are listed below. For which one of them the standard electrode potential $(E^o_{M^{2+}/M})$ value has a positive sign?

Which of the following is not a polyamide?

$A$ capacitor of capacity $0.1 \mu F$ connected in series to a resistor of $10 M \Omega$ is charged to a certain potential and then made to discharge through the resistor. The time in which the potential will take to fall to half its original value is (Given,$\log _{10} 2=0.3010$ ) (in $~s$)