What will happen to the universe billions of years from now?

What are two reasons for why a species might disappear from the fossil record?

Despite the differences in mature plant cells, all of them are derived from meristem cells. the three major types of tissue systems develop from the meristem. meristems develop cells in all but which tissue?

Which of the following must be true for a fossil organism to be useful as an index fossil? a. the fossil organism must be widespread geographically. b. the fossil organism must be abundant. c. the fossil organism must be limited to a short span of geologic time. d. all of the above.