Which is a safe practice for handling chemicals in a lab investigation? a. dispose of all chemicals down the sink with a lot of water. b. tell the teacher about any chemicals that were spilled in a lab. c. identify chemicals by smelling and tasting them. d. place beakers of chemicals near the edge of the counter.

What mistake did john needham make that caused him to conclude that spontaneous generation for microorganisms occurred? a. he re-contaminated his boiled broth solutions. b. he destroyed the vital force in the solutions. c. he did not boil his broth solutions, only warmed them. d. he failed to seal his flasks of boiled broth. e. he allowed his assistant to conduct the experiment which he did not monitor closely.