Now, a lot depends on the terms of the loan. Home mortgages are structured differently than corporate debentures; payment schedules are a lot different and principal repayment (sinking funds in the old days’ term) is strictly separate from interest. (this last one took a lot of getting used to in dealing with mortgage lenders; I was not used to the idea of loans with a fixed monthly payment.)

Historical note: the home mortgage up until the 1930’s was usually what is called a “balloon” mortgage now: only limited repayment of principal during the life of a loan. A worse feature was that the lender often had the power to “call” the loan in advance: demand payment/refinancing of the loan (the opposite of the Fuqua example above where the borrower had the power to force the lender to accept repayment).
Many of these features were sharply limited by law (balloon mortgages may be illegal or sharply restricted) or custom. Further Fanny and Freddy were created to come up with a new sort of mortgage designed to be “saleable”.
I feel the Mortgage Crisis bill that is about to pass may be the Smoot-Hawley Act of 2008: what starts things to finally collapse.