A common characteristic of mitochondria and chloroplasts would be their similarity in membrane structure. Both organelles have an inner and outer membrane. The outer membrane helps with protection while the inner membrane acts to increase surface area so that the organelle's functionality is maximized. The mitochondria have folds and the chloroplast has thylakoid stacks (both help to increase surface area). Another common characteristic would be their function. Both organelles transform energy. The mitochondria takes chemical energy stored in the bonds of glucose and create ATP that is usable in the cell. The chloroplast takes radiant energy from the sun and transforms it into chemical energy in the form of glucose which is the food source for the plant.
Work Step by Step
See page 109 section 6.5, first paragraph. Also figure 6.17 and 6.18