Everyone is a few seconds late to class now and then, including myself. I don't have a problem with that. If you miss a class it is up to you to find out what work you missed. It is better to ask me than a friend. For excused absences you have as many days as you were absent to make up your work.
Work missed due to an unexcused absence generally receives a zero grade.
If you miss a class on the day of a test or quiz, and were present during the review class period, you are expected to take the test on the day of your return during a free period or after school. If you've been out several days before a test or quiz, you will be allowed time to prepare, but generally you have no more that a week to make up a quiz or test after absence. Get to classes on time. See, hear, and understand required information. Take action in a timely manner on tasks requested of you.