Asubstance that form hydrogen ions when dissolved in water is called a ?

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?

18. over time, how do sand dunes tend to migrate? a. perpendicular to the movement of the wind b. in the same direction as the wind blows c. toward the wind d. in random directions

The human body needs energy in order to carry out life processes such as breathing. where does the body get this energy? a. from eating food b. from learning about new things c. from lying in the sun d. from sleeping