Question

List - I shows various cloning vectors and List - II indicates their DNA insert sizes. Match List - I with List - II correctly.

List - I	List - II
A. Plasmid pBR322	I. 0.5-3.0 Mb
B. Cosmid	II. 0.01-10 Kb
C. BAC, \(\text{P}_{1}\)	III. 35-50 Kb
D. YAC	IV. 50-250 Kb

Choose the correct answer from the options given below:

• A. A-II, B-III, C-IV, D-I \
• B. A-I, B-II, C-III, D-IV \
• C. A-IV, B-II, C-III, D-I \
• D. A-III, B-I, C-I, D-IV

Hint:

Sort your vectors by size capacity: Plasmids are the smallest (Kb scale), Artificial Chromosomes like YAC are massive giants (Mb scale).

Answer 1

The Correct Option is A

Step 1: Concept Cloning vectors are specialized DNA molecules used to carry foreign genetic material into a host cell. Different vectors are engineered to handle different maximum insert sizes based on their structural limitations.

Step 2: Meaning * $\text{Kb}$: Kilobases ($10^{3}$ base pairs). * $\text{Mb}$: Megabases ($10^{6}$ base pairs).

Step 3: Analysis * Plasmid pBR322 (A): A small, standard circular bacterial plasmid vector built to hold smaller gene fragments ranging from 0.01 to 10 Kb $\rightarrow$ (A-II). * Cosmid (B): A hybrid vector containing lambda phage cos sites, optimized to hold medium-sized genomic fragments between 35 and 50 Kb $\rightarrow$ (B-III). * BAC (Bacterial Artificial Chromosome) (C): Engineered using the low-copy F-plasmid system to stably maintain large genomic inserts from 50 to 250 Kb $\rightarrow$ (C-IV). * YAC (Yeast Artificial Chromosome) (D): Features yeast centromeric and telomeric regions, allowing it to carry massive eukaryotic chromosome pieces from 0.5 up to 3.0 Mb $\rightarrow$ (D-I).

Step 4: Conclusion The correct matching sequence from smallest to largest capacity is A-II, B-III, C-IV, D-I. This corresponds to option A. Final Answer: (A)