Which type of tissue forms the woody portion of a sycamore tree? secondary phloem
secondary xylem
primary xylem
primary phloem

Some birds look for food near cattle and other livestock. the movement of the cattle churns up the ground, making insects available to the birds. the cattle appear to be unaffected by the presence of the birds. what kind of relationship exists between the birds and the cattle? o a. parasitism o b. commensalism o c. predation o d. mutualism

What would most likely happen to a unicellular organism if it was exposed to a hypotonic solution for an extended period of time?

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