CBSE Class 12 Biology — Biotechnology: Principles and Processes

Match Column-I with Column-II and choose the correct option : Column-I: a. Biolistic gun, b. Chitinase, c. Ti, d. Ca++ Column-II: i. Bacterial cell, ii. Tumour inducing, iii. Animal cell, iv. Fungal cell, v. Plant cell

Which of the following statements about plasmids is incorrect ?

Study the sequence of bases in a DNA molecule that is shown below and answer the questions. 5' – GAATTC – 3' 3' – CTTAAG – 5' (a) What are such sequences called? Name the enzyme used that recognises such nucleotide sequences. [1] (b) How do these enzymes function? [1]

Observe the given picture carefully. A mixture of DNA with fragments ranging from 100 base pairs to 1800 base pairs were separated by electrophoresis on agarose gel with the following arrangement: [Diagram 1 provided.] (a) What result will be obtained in staining with ethidium bromide? Explain with reasons. [1] (b) The above setup was modified as shown below and a band with 100 base pairs was obtained at X. [Diagram 2 provided.] What changes were made to the previous design to get a band at 'X'. Why did the band appear at 'X'? [2]