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Nucleus is the control centre of the cell and manages all the cellular activities taking place inside the cell. It consists of four parts :-
- Nuclear membrane,
- Nucleoplasm,
- Chromatin material and
- Nucleolus.
The Chromatin material(Condensed - Chromosome) stores the cell's DNA which is transmitted to next generation.
I might be incorrect, but from what I remember it should be particle size
Mouth or nose. Then goes into your trachea and into your lungs
Tight junctions hold the cells together as a rivet would in hardware so it can't be taken apart. This makes it so skin and intestines are very strong and don't break very often