Which is true of secondary succession? a. it happens after new land is uncovered. b. it begins on nonliving rock and land. c. it occurs in land and marine communities. d. it takes place on land that had no life.

I think it is C, since it does occur on land life, and I think it also occurs in marine life.

good one: produce hormones that plants grow.

bad one: the problem with organic matter is that while plant nutrients are needed for crop growth, they can also stimulate excessive growth of the wrong plants – mainly, algae.

c) 50% there are four chromosomes. after crossing over, 2 of the four have been changed. that means any gamete has a 2 in 4 chance or 50% chance of receiving the mutated chromosome.