Question

Which of the following best describes the control group in Johnson's experiment on the effects of trematode parasites on the developing limbs of tadpoles?

1) Tadpoles grown in the absence of trematode parasites
2) Tadpoles allowed to grow in nets in their natural environment
3) Tadpoles grown in the presence of only one trematode parasite
4) Tadpoles grown in a tank in which the concentration of trematode parasites was similar to the parasite concentration of ponds in which deformed frogs had been found
5) None of the above

Answer 1

The control group in Johnson's experiment consists of tadpoles grown in the absence of trematode parasites.

Step-by-step explanation:

The control group in Johnson's experiment on the effects of trematode parasites on the developing limbs of tadpoles is option 1) Tadpoles grown in the absence of trematode parasites.