Cane toads are large, nonnative, poisonous toads in Australia. After cane toads entered Australia, scientists observed that the average head size in a
population of toad-eating snakes was getting smaller. Snakes with smaller
heads are not able to eat the large cane toads. What type of situation is this?
O A. Disruptive selection
B. Species richness
C. Directional selection
D. Genetic variation

One function of the poly-a tail on eukaryotic mrna sequences is to the mrna be transported from the nucleus to the cytoplasm. prokaryotic mrna also has a poly-a tail. choose the best explanation of the prokaryotic poly-a tail. a. prokaryotic poly-a tails have the same functions as eukaryotic poly-a tails, because this process is highly conserved throughout different species. b. prokaryotic poly-a tails aren't important, because prokaryotes don't have nuclei. c. prokaryotic poly-a tails have other functions, because prokaryotes don't have nuclei. d. prokaryotic poly-a tails are composed of a different molecular structure compared with eukaryotic poly-a tails.

Which would best keep the oxygen cycle stable? a. cutting down jungles to create farmland b. eliminating parks in large cities c. dumping toxic chemicals into the ocean d. reducing the amount of deforestation d. reducing the amount of deforestation

Control of the body is accomplished by which of the following body systems? nervous system and circulatory system endocrine and repertory system circulatory and respiratory systems nervous system and endocrine systems