Certain fossils, called index fossils, help geologists match rock layers. To be useful as an index fossil, a fossil must be widely distributed and represent a type of organism that existed for a brief time period. Index fossils are useful because they tell the relative ages of the rock layers in which they occur.
Answer:
the cell wall
Explanation:
cell membrane is not rough and it doesn't support or protect the cell.
cytoplasm is the inner environment of the cell that includes organelles and nutritions. it's not rough and doesn't support or protect the cell.
Animals need to eat or consume food
Answer:
B. methane
Explaination: ...............................
All eukaryote cells lack a nucleus