Which phrase describes the role of the mitochondria?
a. where proteins are manufactured
b. where genetic material is housed
c. where cells control water content
d. the powerhouse of the cell

the law of original horizontality explains:   why rocks appear in layers. correct answer: b the law suggests that all rock layers are originally laid down (deposited) horizontally and can later be deformed.   the principle is used by geologists to make assumptions about the relative ages of sedimentary rocks.