Here are some past essay questions:
A short, simple explanation of Mendel’s work:
Mr Andersen talks you through Genetics:
And here Paul Andersen introduces A Beginner’s Guide to Punnett Squares in a 12m 15s tutorial. He also gives examples of monohybrid crosses and one example of a dihybrid cross (which we don’t need to know for SL).
An animated, narrated tutorial on Mendel’s experiments & genetic crosses from Sinauer Associates.
In Crash Course Biology #9 – Heredity, Hank and his brother John discuss heredity via the gross example of relative ear wax moistness.
Inheritance of blood types: