I can only think of one and it is because they occupy different niches (roles in the ecosystem)
I think it's the simple columnar epithelium.
Answer:
two (a pair)
Explanation:
Centrioles are the pair of hollow cylinders that are located near the nucleus in the cytoplasm in a non-dividing cell. Two centrioles together make a centrosome. Centriole duplication occurs before cell division as the duplicated centrioles take part in the formation of the spindle apparatus. However, cytokinesis distributes one pair of centrioles to each daughter cell. Therefore, after cytokinesis, two centrioles are present in each daughter cell.
If a chemistry student is given a molecular formula of a molecule, she or he can easily and readily identify if it is compound by checking the bond either a covalent bond or ionic bond. Check the items of each element since elements in a compound are in fixed ratio, she or he can easily identify.