Final answer:
Mitochondria are organelles involved in cellular respiration, producing ATP. Localization of proteins into mitochondria is facilitated by specific signal sequences.
Step-by-step explanation:
Mitochondria are membrane-bound organelles that are involved in the process of cellular respiration, producing ATP, the cell's energy source. Localization of proteins into mitochondria is facilitated by the presence of specific signal sequences in the proteins. These signal sequences direct the proteins to the mitochondria and allow them to pass through the mitochondrial membranes.