Yulia is twenty-four years old. She has been fit and lean her whole life and recently has begun to put on an unhealthy amount of weight. She goes to her doctor because she is not eating any differently than she has before, yet she is now heavier. What will Yulia’s doctor most likely tell her?

Eukaryotic cells are theorized to have evolved from prokaryotes called the endosymbiotic theory. this explains that the most primitive eukaryotic cell engulfed a prokaryotic cell (by the process of phagocytosis) that is capable of cellular respiration and another prokaryotic cell that is capable of photosynthesis. these prokaryotic cells eventually became organelles and these organelles are the mitochondria and the chloroplast