Which one of the following discoveries involving dna happened first? a. hershey and chase used bacteriophages to confirm that dna was the genetic material in genes. b. griffith learned that a chemical changed harmless cells into harmful cells. c. avery discovered that dna was responsible for storing and passing information through generations. d. sequencing an entire human genome was completed.

What was dr. willem johan kolff’s first step in using the scientific process to invent the hemodialysis machine? he built the machine and tried it with various patients, collecting data about its effectiveness. when a patient’s kidneys failed, he wondered if it would be possible to perform kidney functions with an external machine. he researched and collected data about numerous patients who exhibited symptoms of kidney failure. he drew conclusions from studies of various symptoms of kidney failure, and drew a design for the ideal external blood-processing machine.