a) Origin of Replication: In the genome, there is a specific sequence from which replication commences, so any DNA fragment linked to this sequence can be made to replicate within the host. The linked DNA contains this sequence as well as a control mechanism for its copy number. Thus, to clone DNA from a target in many copies, one should use a vector whose origin supports cloning multiple copies.
b) Bioreactor: A bioreactor is a vessel that allows microbes, plants, and animals to convert raw materials into specific products through the action of their enzymes. By using a bioreactor, optimal growing conditions can be achieved, and desired outcomes are achieved. Bioreactors of the stirring type are the most common. Stirred tank bioreactors are typically cylindrical vessels or vessels with curved bases to facilitate mixing. The fanning of sterile air bubbles in the stirred tank bioreactor is responsible for providing clean air to the cells. The stirrer facilitates mixing and oxygenation within the bioreactor. There are several bioreactor components, such as an agitator system, an oxygen delivery system, a foam control system, a temperature control system, and a pH control system.
c) Downstream Processing: A series of processes are applied to the product before it is made into a ready for marketing product. Separation and purification are two of the main functions. Preservatives are then added to the product. Clinical trials must be conducted on such preparations, as with drugs.