What is the legal ramification if my mom passes away during the night when she is alone?

depends on the jurisdiction. I was a police officer in Maryland for 26 years. The Medical Examiner (coroner) actually rarely came the scene of an unattended death of an elderly person. Usually paramedics were dispatched and the coroner would declare death after speaking on the phone to them. I, as an officer would take a report and confirm with the ME that there were no signs of suspicious activity.

The body would then be picked up and transported to the funeral home by the funeral home. Within a day or two, the ME would stop by the funeral home and a death certificate would be issued by him.

If the person is on hospice care, you simply call hospice and they take care of the rest.

You call 911 to report a death. Officers come to the house. They send a coroner who can actually declare the person died. The coroner calls her MD, who can confirm the patient was dying. All of you will have to answer a whole lot of questions from the police. You call the funeral home ONLY after the coroner hands you a death certificate. Now let's say the MD is out of town. The coroner takes the body away for autopsy. The DA decides whether or not to press charges based on the autopsy.

It's highly unlikely an autopsy would be done on an 107 year old.

What jeannegibbs wrote is true. If you put your mom on hospice they'll take care of everything for you. You call them when the time comes and they come over and go through the necessary procedures. It's very quiet and calm.