The molar ratio of insert DNA to vector DNA used in a ligation is generally about 3:1. Using a vector that is 12 kb and an insert that is 4 kb, how much insert would you use if you used 30 ng of vector?

Therefore, required mass of insert DNA is 30 ng

Explanation:

DNA ligation is the process of joining two DNA fragments together through the action of an enzyme for example DNA ligase. The vector DNA often a plasmid is used to insert a desired DNA sequence into a host cell DNA.

The formula for the calculation of required insert DNA mass is given below:

Required mass insert (ng) = desired insert/vector molar ratio x mass of vector (ng) x ratio of insert to vector lengths

Desired insert/vector molar ratio = 3 : 1

Mass of vector = 30 ng

Ratio of insert vector lengths = 4 : 12 = 1 : 3

Required mass of insert DNA = 3/1 × 30 ng x 1/3 = 30 ng

Therefore, required mass of insert DNA is 30 ng

enzyme active site and substrate specificity

enzymes bind with chemical reactants called substrates. there may be one or more substrates for each type of enzyme, depending on the particular chemical reaction. in some reactions, a single-reactant substrate is broken down into multiple products

im not intirely sure but i think the anwser is d relative humidity