Apple's current CEO Tim Cook tried to help out the late Steve Jobs by offering up part of his liver, when Jobs was in dire need of a transplant. Jobs refused and yelled at Cook for the offer, according to the Hollywood Reporter.

The whole incident is described in the upcoming Steve Jobs biography "Becoming Steve Jobs" by technology reporter Brent Schlender and Fast Company executive editor Rick Tetzeli.

In the excerpts it details Cook found out he had the same type of blood, a rare type, to that of Jobs and could give part of his liver to Jobs -- both his and Jobs' liver would regenerate to whole organs.

Cook visited Jobs in his Palo Alto home and made the offer. Jobs refused though.

"He cut me off at the legs, almost before the words were out of my mouth," Cook said. "'No,' he said. 'I'll never let you do that. I'll never do that.'"

In the book excerpt, Cook remembers Jobs "popping up in his bed" and saying, "No, I'm not doing that!" This was one of the very few times that Cook remembers Jobs yelling at him in the 13 years he knew him.

Cook recalls, even though Jobs was very sick and could have definitely benefited from the liver transplant, he did not allow Cook to be a donor.

"Somebody that's selfish, doesn't reply like that," Cook said.

"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." 

Jobs passed away in 2011, losing his battle to pancreatic cancer. A few months before his death, he named Cook the next CEO of Apple.

To read more excerpts from the book, go to Fast Company's website.