The cell cycle is regulated by both external and internal factors.

part a: list two external factors that influence the cell cycle and briefly describe them. (2 points)

part b: list two internal factors that influence the cell cycle and briefly describe them. (2 points)

Select the correct answer. which statement applies only to the axial skeleton, not the appendicular skeleton? a. it contains a pivot joint. b. it has muscles attached that work in pairs. c. it contains red bone marrow. d. it possesses fossa for bone articulation. e. it protects the heart and lungs.