I think the hydra lacks the specialized cells for touch and chemical detection. On the other hand earthworms have touch, light, vibration and chemical receptors along the entire body surface. Both of them are invertebrates (those animals without a backbone), they include insects, worms, jelly fish, spiders among other animals.
in the nucleolus of the cell
The kind of cell division that goes with growth is Mitosis. Mitosis cell division is accompanied by cellular enlargement and differentiation, so there is an increase in size and weight. I hope this helps!
Why won’t it let me answer
