Answer:
The rainshadow effect causes Natural desert formation.
Answer:
1/ Climate change
2/ Asteroid impacts
3/ Massive volcanic eruptions
4/ Sun explodes
etc. (all the things above are most likely to happen but alien invasion or things like that is also a theory that you can add depends mostly if you like it or not)
In mitosis which produces body cells, each daughter body cell would have 46 chromosomes.
But during meiosis which produces sex cells, each daughter sex cell would have 23 chromosomes.
the human body's system to reproduce