What important event in animal evolution marks the beginning of the cambrian period?

a. the appearance of fossils

b. the appearance of hard parts

c. the ability to swim

The hypothesis of continental drift states that earth's continents, which are located on tectonic plates, move relative to each other. which of the following is true of the movement of the tectonic plates? a. tectonic plates only move once every million years. b. they move at a rate of approximately 5 centimeters per year. c. tectonic plates never move, only the continents located on them do. d. their movements are very rapid and occur at random times.

2. if scientists identify an animal with bilateral symmetry and no segmentation, which phylum can it definitely not belong to? a. roundworms b. annelids c. mollusks d. flatworms

Cultures of the lake of the ozarks water samples were grown on enrichment media for identification. however, these organisms are present to some degree in all samples. an important question from a clinical perspective is whether or not there is a significant increase in the fecal coliform populations that would put people's health at risk. if you were part of the team investigating this outbreak, how would you best enumerate the fecal coliform threat? view available hint(s) cultures of the lake of the ozarks water samples were grown on enrichment media for identification. however, these organisms are present to some degree in all samples. an important question from a clinical perspective is whether or not there is a significant increase in the fecal coliform populations that would put people's health at risk. if you were part of the team investigating this outbreak, how would you best enumerate the fecal coliform threat? direct microscopic counts filtration count culture serial dilution count culture plate count culture