How many atoms of nitrogen are in a sample that weighs 1.25 g?

What re the two main phrases of the cell cycle.

What is true of all organisms in the kingdoms protista, plantae, fungi, and animalia? a. they are multi-celled. b. they are photosynthetic. c. they have cells that contain membrane-bound organelles. d. they contain cells that lack membrane-bound organelles.

Is there any species that went extinct in recent years due to natural causes (not caused by human interaction). if so, what caused it?