Question

Alzheimer's disease is a progressive, degenerative, and irreversible disease. what does this mean

Answer 1

It means that it will progressivley worsen, it cannot be fixed or reversed, and that there is a loss of organs or tissue, but i believe it means that they lose function of their memory 

Answer 2

This means that the disease takes a period of time to fully take effect and also cannot be cured. It also gives you a loss of function in the organs or tissues.