Joint and separate liability

Can anyone explain what joint and separate liability means in practice?

For example, in a situation where two people have a
loan with joint and separate liability to buy into a property investment in the UK with a separate bank. One has 1/3 and the other 2/3rds of that investment. Could the one with the smaller holding be held liable for the whole amount?

Also if banks are holding a property as collateral for a loan they can obviously take that. However can they also go after assets which are held jointly in husbands and wife's name?

Thanks for any clarification

I haven't heard that term before and I wonder do you mean "joint and several liability" - explained here - http://en.wikipedia.org/wiki/Joint_and_several_liability

apologies - yes that is what I meant. Seems to be quite clearly explained there.

In the circumstances I outlined I assume this means the Bank can sue the person with smaller obligation for the full amount. Obliviously it will also take the collateral provided can the bank also go after personal property if it is also in wife's name?