BELLEFONTE, Pennsylvania (CNN) -- Opening statements in the trial of Jerry Sandusky, the former Penn State assistant football coach charged with child rape, were under way Monday.

Joseph McGettigan, prosecutor for the Commonwealth of Pennsylvania, began speaking at about 9:45 a.m.

"You'll hear about systematic behavior by a serial predator," he told jurors. "These were experiences that took place not over days, not over weeks, not over months ... but over years."

Sandusky, 68, has been under house arrest since being charged with sexually abusing 10 boys over a period of at least 15 years. Prosecutors allege that he met some of his accusers through Second Mile, a charity he created for underprivileged children. He has pleaded not guilty.

As McGettigan spoke Monday, childhood pictures of eight of the 10 alleged victims were shown on a projector screen, and the alleged victims were identified by their first names.

McGettigan described to the jury the extent of each victim's contact with Sandusky. One, known as Victim 4, received "a multitude of gifts" from Sandusky and accompanied him on trips to the Alamo Bowl and the Outback Bowl, the prosecutor said.

Feelings of humiliation, shame and fear, led to "years of silence" on the part of accusers, the prosecutor said.

The prosecutor reminded jurors that Sandusky, not Second Mile or Penn State, was on trial. But, he said, Second Mile represented "the perfect environment for a serial predator."

McGettigan's opening statement followed about 20 minutes of jury instructions from Judge John Cleland. "You are the conscience of the community," he told the panel.

In interviews after his arrest, Sandusky acknowledged showering and "horsing around" with boys but denied being sexually attracted to them. He has pleaded not guilty to the charges.

McGettigan referred to those interviews during his opening statement, saying, "Deny what you can ... and make an excuse."

A jury of five men and seven women, along with four alternates, was selected last week. Half of the 16 jurors and alternates have ties to Penn State, including one retired professor and one current professor, three graduates, two employees and one current student, showing the prominence of the university in the local community.

Authorities allege that Sandusky abused some of the boys on the Penn State campus. The case has shaken the school, raised questions about its response to the allegations and drawn criticism from those who claim Penn State put its reputation ahead of protecting potential child victims.

University President Graham Spanier and iconic head football coach Joe Paterno lost their jobs soon after Sandusky's arrest amid criticism they did not adequately handle the matter when allegations involving Sandusky arose years earlier. Paterno died of complications from lung cancer in January.

Mike McQueary, a former graduate student considered to be a key witness in the Sandusky case, has testified that he alerted Paterno in 2002 that he'd seen what appeared to be Sandusky sexually assaulting a boy in a shower in Penn State's athletic facilities, an allegation that authorities didn't learn of until years later.

Paterno apparently told the university's athletic director, Tim Curley, but no one notified police. Curley and Gary Schultz, Penn State's senior vice president for finance and business, are now facing felony charges of perjury and failing to report the allegations to authorities.

Prosecutors said later that the McQueary incident took place about a year earlier than what was originally alleged, causing defense attorneys for Curley and Schultz to argue that one of the charges should now be dropped. Both of them have pleaded not guilty, and their attorneys have said that prosecutors "charged this case before (they) knew the facts."

On Monday, defense attorneys requested that the grand jury testimony of Curley, Schultz and Spanier be admitted into evidence, saying they anticipate the three would invoke their Fifth Amendment right against self-incrimination if called to testify.

The defense also asked that if prosecutors attempt to enter portions of Sandusky's autobiography, "Touched," into evidence, that the entire text be admitted. Defense attorneys said they believe excerpts or "select snippets" may be used by prosecutors to mischaracterize Sandusky's "Motivations, purposes and actions, and attempt to use those excerpts to prove actions in conformity with their theories of how he propagated the alleged abuse."

The Sandusky trial is expected to last about three weeks.

Prosecutors plan to call more than 50 witnesses, and the defense plans to call about 100. Witnesses during the trial are expected to include Jay and Sue Paterno, coach Joe Paterno's son and widow, among others. Defense attorneys have said their list will also include seven Sandusky family members.

Several of Sandusky's alleged victims asked to have their identities protected during the trial. But Cleland ruled against that request, saying "courts are not customarily in the business of withholding information."

However, the judge noted, "It is also to be hoped that various news organizations that will report on the trial will use what has become their professional custom to protect the privacy of alleged victims."

CNN generally does not identify alleged victims of sexual assault.

Cleland also told members of the jury pool that jurors in the case will not be sequestered, saying he will trust them not to read newspapers or follow the case online.

"It's important nobody in the world will know as much about this trial as the people sitting in that jury box," he said last week.

CNN's Laura Dolan and Dana Garrett and In Session's Michael Christian and Jessica Thill contributed to this report.