Andy Dawson nearly opened the scoring for Hull early on but his curling left-footed free-kick from 20 yards was well tipped around the post by Scunthorpe keeper Joe Murphy.
From the resulting corner the home side came even closer to taking the lead as Ian Ashbee rose to Dawson's curling cross and fired in a header from close range, but keeper Murphy was equal to it as he parried the ball away to safety.
Phil Brown's men did take the lead on 27 minutes as Craig Fagan hit a shot from ten yards which Murphy could only dig out onto the head of Pedersen and he made no mistake from four yards to send Hull into a deserved lead.
The Tigers went further into the lead ten minutes later as a pinpoint corner from Dawson went straight to the air-born Turner, whose bullet header from six yards saw the ball fly into the back of the net.
Scunthorpe came close to grabbing one back midway through the second half as Ben May made space for himself and struck a right-footed shot from 25 yards, but the ball sailed just over the top of Boaz Myhill's crossbar.
Dean Marney nearly had Hull 3-0 up around the 70th minute mark as he skipped past two players and hit an arrowed left-footed shot from just outside the box which was saved by Murphy onto the right-hand post and out for a corner.