The correct Option is : 2
Examine the role of cellophane tubes :
Structural support to dialysis machines: Cellophane tubes are not used for structural purposes.
Acting as semipermeable membranes: Historically, cellophane was utilized in hemodialysis machines for its semipermeable properties, allowing selective passage of substances like toxins and excess salts from the blood while retaining blood cells and essential proteins.
Delivering medication to patients: Cellophane tubes are not used for medication delivery.
Filtering blood cells directly: While cellophane membranes allow for filtration, their primary role was to act as semipermeable barriers rather than directly filtering blood cells.
Conclusion: The historical use of cellophane tubes in hemodialysis was primarily due to their semipermeable properties, enabling effective dialysis by filtering waste products from the blood.
Answer the following questions:
(a) [(i)] Explain how some strains of Bacillus thuringiensis produce proteins that kill certain insects such as lepidopterans but do not kill the Bacillus.
[(ii)] How is the above mechanism exploited for the production of Bt cotton plant by biotechnologists?
(b) [(i)] Explain how the amplification of gene of interest is done using PCR.
[(ii)] State two applications of the desired amplified fragment of DNA.
The basic scheme of the essential steps involved in the process of recombinant DNA technology is summarised below in the form of a flow diagram. Study the given flow diagram and answer the questions that follow.
(a) What is the technical term used for Step 4 in the above process?
(b) Which of the given two combinations of restriction enzyme should be used in Step 1? Justify your answer.
(i) EcoR I to cut the plasmid and Hind III to cut the alien DNA.
(ii) EcoR I to cut both the plasmid and alien DNA.