"You want to test the mutagenicity of a certain chemical that you suspect causes changes to DNA molecules. You have not been able to locate the Salmonella typhimurium strain that requires histidine in order to grow. What might you be able to use instead?"

Which of these statements best describes the st. lawrence seaway? the st. lawrence seaway connects the st. lawrence river with the arctic ocean. the st. lawrence seaway provides an important trading route between the u. s. and mexico. the st. lawrence seaway provides an important trading route for the u. s, but has little value for canada. the st. lawrence seaway connects the great lakes, the st. lawrence river, and the atlantic ocean.

Living cells cannot use heat to provide the activation energy for biochemical reactions because which choice(s) complete the sentence correctly? a) answer choice ii. eliminate b) answer choices ii and iv. c) answer choice iii and iv. d) all answers can complete the sentence.

What advantages does a pedigree have over a written passage?