Can you imagine a peanut butter sandwich without the jelly? It’s a tough sell for two ingredients that have been wedded for so long.

That’s part of the challenge Apple now faces with Steve Jobs’ decision to take another medical leave of absence and to hand over the day-to-day operations to Tim Cook, the company’s chief operating officer.

From Wall Street to Silicon Valley, there’s widespread acknowledgment that Jobs’ close relationship to the Apple brand and the company’s employees is something that can’t easily be replicated. Here, a look at some of the questions circulating about where the company will go from here.

Will Apple’s stock suffer from Jobs’ absence?

There’s a lot riding on Apple’s stock: With a stock market value of $321 billion, it’s second only to Exxon Mobil, according to Bloomberg. On Tuesday, some investors sold shares, causing about a 4 percent dip in its share price. Apple stock recovered slightly before the end of the trading day as Apple prepared to announce its quarterly earnings.

“The outlook for Apple’s stock is terrific whether or not Steve Jobs ever returns to the company,” says Charles Wolf, a senior analyst for Needham & Company.

Wolf says Apple has plenty of room for growth because it remains a “small fish” in three very large ponds including the computer, smart phone and tablet markets.

Also, this isn’t the first time Jobs has taken a medical leave.

“Investors have seen that Apple can prosper in the absence of Jobs,” Wolf says. “It did so in 2009 and it’s in a better position to do so today.”

Can Apple create the next big thing without Steve Jobs?

Apple has succeeded in creating demand for products that consumers didn’t know they wanted or needed. Most of these have been under Jobs’ watch.

“In Jobs’ absence, however, it’s unlikely that Apple will come out with yet another big thing — that is a product that disrupts and redefines another industry, as the Mac, iPod, iPhone and iPad did,” says Wolf.

Even before Apple announced its CEO’s decision to take another medical leave, investors were questioning what realms Apple could still conquer.

What’s on Apple’s plate for the future?

Over the past decade, Apple greatly expanded its retail stores in the U.S. Wolf says Apple is now “rapidly expanding abroad” — with an especially large presence in China.

And even though there are countless new consumer technology devices unleashed every year, there’s still room for more.

“I think we’re just beginning,” says Dave Farber, distinguished career professor of computer science and public policy at Carnegie Mellon University. “Of all the companies around, Apple has the most potential for continuing the innovation. Most of the computers we have now marginally talk to each other and marginally talk to the environment around them.”

Farber sees a future where his iPhone integrates with computers in his home to seamlessly control everything from music to temperature settings.

Why do Steve Jobs and Apple’s future appear to go hand in hand?

There’s a reason Jobs takes center stage at all of the company’s major announcements: “People believe him,” Farber says.

While Apple has more than a good bench of executives to draw from as potential replacements, most haven’t been in the spotlight.

“The headache is that they’ve been relatively invisible,” Farber says. “It’s not just whether they can manage things.”

What impact does Jobs’ departure have on Apple’s employees?

Farber says Jobs, who co-founded Apple in 1976, has played a similar role to David Packard, the co-founder of Hewlett-Packard and Andy Grove, the co-founder of Intel.

Beyond functioning as the CEOs, Farber says, these executives embodied the spirit of their companies, guiding them down the right path.

“Most CEOs don’t have the prestige or the power to drive the company — to put the spirit of the company and the goal of the company into the minds of all the workers,” he says.

Farber says Jobs’ absence was clearly felt when he left the company in 1985: Apple “sort of drifted, almost crashed” without him at the helm.

One of the challenges of finding a replacement for visionary CEOs is that they don’t tend to train their successors. “They carry so much of the weight on their back that it’s hard for their proteges, their inheritors, to get the right set of experiences,” Farber says.”It’s going to be a rough time if he doesn’t come back.” Copyright 2011 National Public Radio. To see more, visit http://www.npr.org/.