Scientists often require keeping a stock of biological
collections because it is not possible for a scientist to every time go out and
get a sample. Scientists may require comparing several of his biological
subjects that might not always be found in the area, so it is important to keep
a collection. It depends on the type and size of the organism in question.
Certain organisms like butterfly may not be available in the area where the lab
is located. So the scientist has to make prior arrangement and keep a stock of
the organism.
