Statement I: The cloning results in amplification of each piece of DNA fragment.

Statement II: BAC and YAC are the vectors used in cloning.

• Cloning involves the replication of DNA fragments within a host organism, typically a bacterium like Escherichia coli or yeast. When you insert a DNA fragment of interest into a cloning vector and introduce it into the host organism, the vector replicates along with the inserted DNA. As the host cell divides, the DNA fragment and vector are also copied, leading to the production of multiple identical copies (clones) of the original DNA fragment. This process indeed results in the amplification of the DNA fragment of interest.
• BAC and YAC vectors are indeed used in cloning, but they serve different purposes and have distinct characteristics:

BAC (Bacterial Artificial Chromosome): BACs are cloning vectors designed to carry large DNA fragments, typically in the range of 100 to 300 kilobases (kb) or more. They are often used for cloning and maintaining large genomic DNA inserts, such as those from complex genomes like the human genome. BACs are replicated in bacterial hosts, particularly E. coli.

YAC (Yeast Artificial Chromosome): YACs are cloning vectors that are used to clone and manipulate even larger DNA fragments, often exceeding 1 megabase (Mb) in size. YACs are unique in that they can replicate in yeast cells, such as Saccharomyces cerevisiae. They are especially useful for studying and maintaining large eukaryotic DNA sequences, including entire eukaryotic chromosomes.