what are vectors in genetics?

Answer 1

A Vector is a small piece of DNA containing regulatory and coding sequences of interest. It is a DNA molecule into which foreign fragments of DNA may be inserted. A vector functions like a "molecular carrier", which will carry fragments of DNA into a host cell.

Vectors are usually derived from plasmids, which are small, circular, double-stranded DNA molecules occurring naturally in the cytoplasm of bacteria. It contain an origin of replication, which enables the vector, together with the inserted foreign DNA fragment inserted into it, to replicate.

Vectors contain genetic markers that allow for selection of cells which have taken up the plasmid DNA.

Vector DNA functions to insert and amplify a gene into a target genome. Vector DNA can be used in a DNA vaccine.

Answer 2

Just adding to Rashmir's and Paw's answers...

Vectors can also be chromosomes. An example is the case of YACs. Yeast Artificial Chromosomes (YACs) have the telomere, replication origin and centromere sequence of yeast chromosomes. Thus you can insert in them large fragments of e.g. human or whatever DNA (up to a million base pairs) and propagate it in yeast cells.

Plasmid, Cosmid and viral vectors can carry much smaller fragments, usually not more than a 20,000 base pairs. However the usual size of fragments that are cloned is below 3,000 and plasmids can be amplified a lot in bacteria and easily purified, making them the most commonly used vector.

Answer 3

vectors are those DNA molecule capable of autonomous replication within a host cell and into which other DNA sequences can be inserted and thus amplified. They are or are derived from plasmids, bacteriophages, or viruses and are used for transporting foreign genes into recipient cells. Genetic vectors possess a functional replicator site and contain genetic markers to facilitate their selective recognition

Answer 4

sorry - t is not known to me