How are immune cells able to detect foreign pathogens?

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

All individuals have two alleles for a given trait. according to mendel's these alleles are passed down one each from both mother and father.

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