What organic substance cuts dna into different sized fragments?

If a set of instructions that determines all of the charactersitics of an organism is comparedto a book,and a chromosme is compared to chaper in the book,then what might be compared to a paragraph in the book?

Fredrick griffith made a scientific discovery in 1928

What property of water provides for appropriate sugar, salt, and amino acid levels to be present and carried in the blood of animals to be delivered to cells