Final answer:
Cleavage of APP protein by beta-secretase alone generates an insoluble and large fragment called is-APP beta.
Step-by-step explanation:
The statement is true. Cleavage of APP protein by beta-secretase alone generates an insoluble and large fragment called is-APP beta. This large fragment is insoluble because it has a tendency to aggregate and form plaques, which are characteristic of Alzheimer's disease. This process occurs in the brain and is a significant factor in the development and progression of the disease.