Platyhelminthes lack A. respiratory system
B. circulatory system
C. skeletal system
D. all of the above

Which of the following occurs most often in a population when genetic variation and overproduction are present? some organisms have a lower reproductive success than others. some organisms have a higher reproductive success than others. some organisms have no reproductive success. some organisms do not have genetic variation.

What organelle other than the nucleus houses dna in a eukaryotic cell?

Jason adds the antibiotic penicillin to a bacterial culture. the bacteria develop genetic modifications in their genome, which gives them resistance to the antibiotic penicillin. what caused this genetic modification?