Living things differences are important because it helps classify and signify one from another
A cactus is a plant the can be found in hot and dry climates. They have a thick stem that usually have spines(thorns) and flowers. Cacti have short growing seasons and long dormant seasons. Cacti are able to absorb water in a very short amount of time. One species is able to absorb up to 200 gallons of water.
There is about 1,500 - 1,800 cactus species known.
No, cells are not dependent on the size of the organism.