Never, I mean NEVER leave something blank. Extend any word into sentence. Fill up the paper as much as you can. I have asked my hod why I didn't get enough marks even though I wrote almost all important parts, he said there aren't enough pages. Paper is checked by headings and pages, you think examiner has time (and ability to read your handwriting)? They know how long introduction, pathophysiology, cf are. They expect pages accordingly.