Scientists first discovered that mitochondria were "energy factories" by measuring their oxygen consumption and .

Dwarf galaxies are select one: a. relatively rare. b. not very bright c. mostly spiral shaped. d. none of these.

In the family tree below, people with the recessive trait of attached earlobes are shaded gray.

Chalk is an ionic compound. which is a property of all ionic compounds that makes chalkboard? particularly useful for writing on a a high melting point hardness and brittleness inability to dissolve in water a multicolored appearance