Which of these is an organ system ?
stomach
mucosa
dog
digestive
gamete

How can you keep track of variables in a science experiment?

Explain why biological control methods are generally environmentally superior to chemical pest control methods.

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.