Two gene copies are identical by descent if
a) two individuals have the same parents
b) one allele mutates to a second allele
c) selfing occurs
d) they are both inherited from the same gene copy in a recent common ancestor.
e) balancing selection maintains two or more alleles

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.