Written By: Plasmid, in microbiology, an extrachromosomal genetic element that occurs in many bacterial strains. Plasmids are circular deoxyribonucleic acid (DNA) molecules that replicate independently of the bacterial chromosome. They are not essential for the bacterium but may confer a selective advantage.
A gnat /ËnÃ¦t/ is any of many species of tiny flying insects in the Dipterid suborder Nematocera, especially those in the families Mycetophilidae, Anisopodidae and Sciaridae. They can be both biting and non-biting. Most often they fly in large flocks resembling clouds.
The beauty of nature. Saturday, 14 August 2010. Hoverflies do not sting and 7 other facts. It is not always easy to tell the difference between a hoverfly (flower fly) and a bee or wasp. There are so many different species of hoverfly and this variety of shapes and sizes adds to the confusion.