The genus of bacteria that is able to fix nitrogen and form heterocysts is a. pseudomonas. b. escherichia. c. vibrio. d. anabaena.

Adigestive system that is a series of tubes beginning at the mouth and ending at the anus is a digestive system.

Recent research by marine biologists suggests that bottlenose dolphins have names for themselves. scientists played sounds they had identified as the names of particular dolphins, putting them through a synthesizer so that they did not sound like the voices of particular dolphins. the researchers found that dolphins would respond to the names of other dolphins that they were related to or associated with, but they ignored the names of strangers. this discovery suggests a much greater degree of self-awareness in aquatic mammals than was previously suspected. if this research holds up, what does it suggest about dolphins?

Aristotle classified animals according to their a. habitat and mating behavior c. mating behavior and relatedness b. habitat and physical differences d. physical differences and mating behavior