There are several external forces that acct on rocks in the rock cycle. Which one is NOT one of these forces?
A. water
B. pressure
C. ice
D. wind

Which of these substances does not protect against invaders in the nonspecific immune response? a. saliva b. mucus c. tears d. urine

What type of plant is good for a bioassay and where can i buy it? i only have a month.

According to theories of how life began, how did early organic molecules begin to separate from the outside world? a: specialized enzymes were required b: chains of amino acids created a barrier c: formation of microspheres or vesicles d: rna catalyzed the formation of membranes