Biotechnology and its Applications Test - 12

Animals that had their DNA manipulated to possess and express an extra(foreign) gene are known as transgenic animals and the process is known as transgenesis. It helps in study of diseases and gene therapy as many transgenic animals are designed to increase our understanding of how genes contribute to the development of disease. Transgenic animals helps in increasing the production of biological products. Also, transgenic animals are used in testing the safety of vaccines before they are used on humans. Hence, the correct option is d.

A biological patent is a patent on an invention in the field of biology that by law allows the patent holder to exclude others from making, using, selling, or importing the protected invention for a limited period of time. Hence, the correct option is c.

Vitamin-A deficiency causes night blindness among children. Vitamin-A deficiency often occurs where rice is the staple food since, rice grain does not contain β-carotene. Three transgenes providing phytoene synthase, phytoene desaturase, beta carotene desaturase and lycopene cyclase activities were transferred into rice by Agrobacterium mediated transformation. The resulting transgenic rice popularly called goldern rice contains good guantities of β-carotene.

Flaw savr is genetically modified tomato, which remains fresh and retain their flavour much longer than normal tomato due to the blocking of synthests of fruit softening enzyme polygalacturonase.

Bt cotton is a genetically modified variety of cotton producing an insecticide. The bacterium Bacillus thuringiensis (Bt) naturally produces chemicals harmful to selective insects, most notably the larvae of moths and butterflies, beetles, cotton bollworms and flies, and harmless to other forms of life. The gene coding for Bt toxin i.e., CRY gene has been inserted into the cotton plant with the help of DNA of bacteria, causing cotton to produce this natural insecticide in its tissues. The bacteria that is used as a vector is Agrobacterium tumefacien.

The plants obtained through genetic engineering contain a gene or genes usually from an unrelated organism, such genes are called transgenes and the plants containing transgenes are known as transgenic plants. These plants are often called as genetically modified or GM crops, eg, Flavr savr tomatoes, golden rice. Plants are made transgenic for identification, expressing the gene activity in tune, to produce several chemicals like fatty acids, sugars, cellulose, rubber, etc.