Which human body system does the mitochondria most resemble and why?

Digestive system resembles to the Mitochondria which is called as power house of cell.

Explanation:

The mitochondria function as digestive system by taking in nutrients and produces energy from them after catabolic process. Mitochondria takes in nutrient rich molecules, break them and produces energy rich molecules. Intestine in the digestive system perform the same function by extracting energy from the food to help body cells work.

mendel's first law states that during the formation of reproductive cells , pairs of hereditary factors for a specific trait separate so that offspring receive one factor from each parent.

explanation:

if the type of the food available changes, then the frequency of beak types will change, because birds with beaks more suited to the available food will be more successful over time.