Problems:
* Missing subject: The phrase "because misses them" lacks a subject. We need to know *who* misses the cells.
* Missing verb: "Misses" is a verb, but it's missing the subject.
Corrected Sentence Options:
Here are a few ways to fix the sentence, depending on the intended meaning:
* Option 1 (Focus on lack of awareness): "The body loses these cells, but no one notices because they don't miss them."
* Option 2 (Focus on the body's ability to replace cells): "The body loses these cells, but no one cares because the body replaces them."
* Option 3 (Focus on the specific person who misses the cells): "The body loses these cells, but no one cares, even though *the doctor* misses them."
Choose the option that best fits the context you are trying to convey.