Apple CEO Tim Cook offered to donate part of his liver to former boss Steve Jobs before the Apple co-founder's death, according to a biography due for publication March 24. The book, “Becoming Steve Jobs,” by veteran tech reporter Brent Schlender and Fast Company executive editor Rick Tetzeli, is expected to offer insight not only on the rise of Apple but also on Jobs' relationship with Cook.

By 2009, five years after being diagnosed with pancreatic cancer, Jobs was so sick that it was difficult for him to leave home. After one visit to Jobs' house, Cook departed “feeling so upset that he had his own blood tested” to see if he and Jobs shared the same blood type, according to an excerpt published by Fast Company. Cook ultimately discovered a partial transplant was a possibility, only to be shot down when positing the idea.

“[Steve] cut me off at the legs, almost before the words were out of my mouth,” Cook said, according to the excerpt:

"Somebody that’s selfish," Cook continues, "doesn’t reply like that. I mean, here’s a guy, he’s dying, he’s very close to death because of his liver issue, and here’s someone healthy offering a way out. I said, ‘Steve, I’m perfectly healthy, I’ve been checked out. Here’s the medical report. I can do this and I’m not putting myself at risk, I’ll be fine.’ And he doesn’t think about it.

It was not, ‘Are you sure you want to do this?’ It was not, ‘I’ll think about it.’ It was not, ‘Oh, the condition I’m in . . .’ It was, ‘No, I’m not doing that!’ He kind of popped up in bed and said that. And this was during a time when things were just terrible. Steve only yelled at me four or five times during the 13 years I knew him, and this was one of them."

Jobs had a liver transplant in March 2009, and passed away at age 56 in October 2011.

The excerpt from “Becoming Steve Jobs” also reports that the Apple founder considered making an offer to buy Yahoo to beef up Apple's search results, and that Jobs hoped Apple would never make another television because of his own disdain for TV.