Have unique, jointed stem structures.

a.
club mosses
c.
horsetails
b.
ferns
d.
spike mosses

Which of the following is most important in making the typical seed more resistant to adverse conditions than the typical spore? a) a different type of sporopollenin b) an internal reservoir of liquid water c) integument(s) d) ability to be dispersed e) waxy cuticle

What term describes a doctor who becomes a specialist by meeting standards beyond those of getting a license and passing a test in the specialty area?

Why are some people more concerned about shark survival than about shark attacks?