Do you know why bacterium plasmids are used for gene cloning but retroviruses are used for gene therapy when they both just modify dna?

This is the diveristy of ecosystems natural communites and habits it is the variety of ways that species interact with each other and their environment

Where would you expect to see seedless plants, such as ferns and mosses? a. in a botanical museum, because they are all extinct b. low and close to the ground in a moist environment c. climbing high while circling the branches of another plant d. deeply rooted in a forest with a trunk that reaches 20 meters or more

Are the layers of rock above and below the coal older or younger?