Answer:
Nutrient cycle is a process  of movement, reuse or recycling of nutrients in that particular environment. They are for both living and nonliving things, elements like carbon, oxygen are recycled through such cycles. 
Nutrient cycle in an ecosystem involve:
- carbon cycle
- nitrogen cycle
- oxygen cycle
- phosphorus cycle
 
        
             
        
        
        
The cell cycle, or cell-division cycle, is the series of events that take place in a cell leading to its division and duplication of its DNA (DNA replication) to produce two daughter cells.
        
             
        
        
        
Dead mustard plants disintegrate into the soil And the worms in the soil see it and are like woah man let’s fricking rave! So these worms rave until the riff of dawn and the air gets so dense it just turns into nitrogen. The rave vibes were so lit that the nitrogen had this gold ora to it. The worms gathered it all and in a way, molded it into a seedling. They were like “ we gonna name it marigold cuz we had a pretty merry good time”. So yea science is wild isn’t it?
        
             
        
        
        
That is true.
Hoped I helped!