Although they were once classed together, archaea and bacteria have now been separated into two different domains. why was this change necessary? . a. the archaea only have cell membranes and the bacteria only have cell walls.. b. the two groups are composed of species with different cell sizes.. c. the archaea have nuclei and the bacteria do not.. d. the two groups replicate their dna in different ways.

Calvin ate a candy bar, which caused his body's blood glucose levels to become unbalanced. his body responded by initiating a feedback mechanism to return his body to homeostasis. place the steps of this feedback mechanism in order, starting with the blood glucose imbalance that occurred after calvin consumed the candy bar. a) calvin's blood glucose levels decreased. b) calvin's pancreas stopped secreting insulin. c) calvin's body cells started to take up glucose and store it as glycogen. d) calvin's blood glucose levels increased. e) calvin's pancreas started secreting insulin.

The idea of spontaneous generation was disproved by in a experiment involving jars of meat

20 how are energy cycles and growth cycles related?