Excused Absences
Please see the Course Description for details - here is a summary: 

You must have something in writing to be excused from a class. If you are too sick to get out of bed you should call Dial-a-Nurse. You must bring any absence excuses to 231/233 Loomis in person along with a filled-out "Course Absence Form" as soon as you return to class.

There are deadlines for getting missed assignments excused so you must not leave this to the end of the semester: Excuse documentation (doctors notes etc) must be turned in within two weeks of the absence.  Excuses from the emergency dean must be turned in within one week of the date on the letter. Excused assignments show up as EX in your gradebook, which means that the absence will not count against your grade. No excuses will be accepted after the semester is over.

According to the student code that governs the university you may not miss a class to take an exam for another course. The course giving the exam must give a conflict exam. Be sure to arrange for that in advance!