Final answer:
The two types of presenilin proteins are Presenilin-1 and Presenilin-2, which are integral to the gamma-secretase complex involved in Alzheimer's Disease.
Step-by-step explanation:
The two types of presenilin proteins are Presenilin-1 and Presenilin-2. These proteins are part of the gamma-secretase complex and play a crucial role in the production of beta-amyloid peptides, which have been implicated in the pathogenesis of Alzheimer's Disease. Errors in the processing of presenilin proteins or their function can lead to an increase in the toxic forms of beta-amyloid peptides, which can aggregate into plaques, a characteristic feature of Alzheimer's pathology.