Figure 3. Decreased mitochondrial size and density in aged mice. Each bar represents the mean ± SD. *p<0.05. **p<0.01 ***p<0.001 (A) Representative images of electron microscopy from FDB longitudinal slices from mice from the different groups (B) number of mitochondria per image area (98 μm2) is significantly increased in the adult group. (C) Mitochondria size is significantly diminished in the young and old groups (D) mitochondrial density, given by area of mitochondria/ area of tissue significantly decreased in old stages of life in mice.