What do Astronauts need to take on the moon so that plants could grow in a lunar plant growth chamber

The meselson-stahl experiment demonstrated that dna replication is semiconservative. in the figure, semiconservative replication is illustrated by

In which specialized organ of the plant would these cells most likely be found

Hurry which of these is true about index fossils? a) are very scarcely found b) used as guides in relative dating c) found in the youngest layer of the rock d) used as reference points in absolute dating