Nucleus for what?
Atom? Animal Cell? Plant Cell? Each have different structures.
If a particular job of a cell was to swim a long distance to an egg with a flagella, then it would need more mitochondria. As mitochondria undergo cellular respiration and essentially utilize the carbohydrates for that particular cell to produce the final product of ATP high energy containing molecules needed for the movement.
Endocytosis is a cellular process in which substances are brought into the cell. The material to be internalized is surrounded by an area of cell membrane, which then buds off inside the cell to form a vesicle containing the ingested material.
Motor neuron disease includes loss of motor neurons in the anterior horns of the spinal cord and motor nuclei of the lower brain stem.