19. B - mitochondria
20. D - vegetative structure
21. C - inducing a mutation
22. A - phosphates
23. C - fungi
24. A - provides support
25. C - sponges
26. B - opposite charges
27. D - asexual reproduction
28. not sure about this one sorry
29. D - all of the above
30. A - prevents ions and large molecules from passing through the membrane