(1) a protein produced by Hordeum vulgare, which is rich in lysine
(2) a toxic molecule isolated from Gossypium hirsutum, which reduces human fertility
(3) a protein produced from transgenic Brassica napus, which prevents blood clotting
(4) an antibiotic produced by a genetically enginnered bacterium, Escherichia coli
(3) Transgenic plants are those plants in which a foreign gene has been introduced and stably integrated into the host DNA. A gene that is transferred using the tools of molecular biology is called transgene. Brassica napas is one of the transgenic plant species. Recently transgenic plants have been explored for production of biologically active peptides and proteins having pharmaceutical applications including use as blood proteins, enzymes, growth, hormones etc. The protein hirudin present in leech, prevents blood clotting. The gene was chemically synthesized and introduced in Brassica napas and later on the seeds contained the protein.