Acontrolled experiment is designed to test whether h. pylori can survive in acidic conditions that are similar to those found in the stomach. a result showing that h pylori cannot survive in that environment would a) completely eliminate the chances that ulcers are caused by bacteria. b) damage the credibility of the theory that h. pylori are the cause of peptic ulcers. c) lend credibility to the theory that ulcers are caused by stress and other physical factors. d) lend credibility to the theory that ulcers are caused by some form of bacteria, albeit not h. pylori.

B. damage the credibility of the theory that H. Pylori are the cause of peptic ulcers.

prophase: we can observe the chromosomes to coil up and condense. they become visible. nuclear membrane and envelope disintigrate.s

metaphase: chromosomes align at the center, the metaphase plate. spindle fibers attach to centromeres of the sister chromatids. they meet at kinetochores.

anaphase: sister chromatids are pulled towards each opposing centromere, set on different poles.

telophase: chromosomes are now clustered up only on either sides of the cell. nuclear membranes reform, and a new cell wall forms along the cell plate. this will lead to cytokinesis, the process that divides the cell membrane and forms the cell wall.

false because ozone (o3) depletion does not cause global warming, but both of these environmental problems have a common cause: human activities that release pollutants into the atmosphere altering it.

global warming is caused primarily by putting too much carbon dioxide into the atmosphere when coal, oil, and natural gas are burned to generate electricity or to run our cars.

explanation: