Amanda Knox covered her head with her arms as graphic photographs and video of British student Meredith Kercher's body were shown in court.
Evidence from pathologist Luca Lalli was held in private without any media or public present after a ruling by the judge, following a request from the Kercher family.
Court sources said American Knox, 21, did not look at the images as they were shown on a video screen and kept her head down while her co-accused and former boyfriend Raffaele Sollecito, 25, glanced at them sporadically.
Knox's mother Edda Mellas, who is in Perugia, Italy, to support her daughter said during a break in hearings: "The images upset her too much and she didn't watch them."
Lalli also told the murder trial Kercher died "around 11p.m." on the night of Nov. 1, 2007, and added her body showed evidence of "sexual activity but could not prove if there had been violence."
Both Knox and Sollecito deny killing 21-year-old Meredith.
Francesco Maresca, the Kercher family lawyer, had requested the evidence be heard in private "out of respect" for Meredith's memory although he said he did not object to audio being heard.
However, trial judge Giancarlo Massei ruled this out and the evidence was heard in private.
Last year images of Kercher's body were shown on Telenorba, an Italian TV station based in Bari, close to where Sollecito is originally from.
At the time, the Kercher family issued a strong condemnation and prosecutors opened an investigation into how the station obtained the footage.
During the closed door hearings, Maresca said it could not be "ruled out that hasty sexual activity, which would not leave signs of resistance, had taken place after she had been threatened with a knife."
Besides Lalli, the court will hear from other medical experts who will explain the wounds that led to Kercher's death through blood loss and choking on her own blood.
Also due to testify is Carlo Maria Scotto di Rinaldi, the owner of an underwear shop where Knox was seen buying lingerie with Sollecito, shortly after Knox was killed.
CCTV footage shows her holding up the underwear and the owner has said he heard Knox say: "I can put this on and have wild sex with you."
Prosecutors are using character evidence such as this to build up a picture of a "cold and unemotional" Knox, which they say points to her being the killer.