Which is characteristic of a mineral? a. it must be man-made and amorphous. b. it must be man-made and crystalline. c. it must be naturally occurring and amorphous. d. it must be naturally occurring and crystalline.

Which prevent errors in dna replication? a. helicase enzyme checks the dna for errors. b. each base can attach to only one other type of base. c. ribosome enzymes prevent errors from happening. d. dna contains no complementary base pairs.

Which of the following matches the organisms described with the correct domain? a. bacteria--unicellular, eukaryotic organisms with cell walls that do not contain peptidoglycanb. archaea--multicellular, eukaryotic organisms that do not have cell wallsc. eukarya--single-celled and multicellular organisms, with a defined nucleus and a variety of nutritional sourcesd. bacteria--unicellular, eukaryotic organisms that always lack cell walls

In which of the following relationships is one organism always benefited while the other organism is always harmed