Rebecca Arnold's fingertips pressed at the synthetic skin to determine where to make the incision.

She was ready to create a temporary airway in a mannequin's throat using a procedure called surgical cricothyrotomy, a delicate but important lifesaving technique used by paramedics when a patient's facial trauma prevents breathing through the nose or mouth.

Arnold pushed the scalpel into the neck and gasped as the instrument snapped.

"That's obviously the difficulty in using plastic models," instructor Dr. John Gallagher said with a chuckle. "The scalpel blade isn't supposed to break off in the tissue."

For the past decade, this is how Phoenix Fire Department paramedics trained for real-life situations. It's how Arnold was learning to provide a patient with air.

But a partnership with Science Care, a tissue bank, has given first-responders a chance to work on the next best thing: cadavers. Phoenix Fire Department paramedics are now practicing invasive procedures on human tissue at the Science Care Bioskills facility in north Phoenix.

"There is no way to reproduce the human body," said Gallagher, director of the Fire Department's Emergency Medical Services. "It's just not the same."

About 20 emergency medical technicians go through the class each month, and Gallagher expects that all 480 paramedics will take the course in the next two to three years.

"Paramedics are now able to see and experience the human anatomy, thus giving them a more accurate understanding of what to expect when faced with true lifesaving situations," Gallagher said. "To do this on a person, it's a million percent better."

Emergency personnel used to train on cadavers with help from the Maricopa County Medical Examiner's Office, Gallagher said. A team of five or six people would go to the morgue whenever a body was available. They worked mostly on the cadavers of homeless people.

A policy change at the morgue seven or eight years ago required family consent to work on the bodies, which essentially squelched the program, Gallagher said. Getting approval proved too challenging.

Science Care charges a fee for lab work. For $250, the company provides about five cadavers per class. The fees cover the costs of removal, processing, procurement, storage and distribution of human tissue.

Billing itself as a "fee-based service organization," Science Care sells cadavers or body parts to agencies nationwide that use them for medical training, surgical-device testing, neurological research and drug development. The company, which is accredited by the American Association of Tissue Banks, distributes tissue only to qualified applicants.

In 2005, about 1,130 people across the country donated their remains to Science Care, according to company President and CEO James Rogers. He said body donation is a way for people to give back to their communities.

"A critical value is the need for medical professionals to practice lifesaving techniques in advance on donated bodies instead of while trying to save a life," he said.

Capt. John Dean, a Phoenix Fire Department paramedic, can attest to the value of practicing on human tissue.

Dean performed his first surgical cricothyrotomy in the 1980s when he encountered a head-on collision while driving home from a fishing trip. A young man had struck his face on the dashboard in the late-night collision and couldn't breathe. Dean said he was able to recall his cadaver training while working on the victim.

That man tracked Dean down a few years ago to say thanks, and he's "actually doing great."

"In a cadaver lab, you're practicing like in the real world," he said. "When you've got the headlights on and it's dark out, you can't put a value on having an experience instead of just looking in a book."