AP BIOLOGY

Detailed explanation-1: -Some different cells have different amounts of mitochondria because they need more energy. So for example, the muscle has a lot of mitochondria, the liver does too, the kidney as well, and to a certain extent, the brain, which lives off of the energy those mitochondria produce.

Detailed explanation-2: -Heart, sperms, and muscle cells contain about 5, 000 mitochondria per cell. These cells need more energy, so they contain more mitochondria than any other organ in the body.

Detailed explanation-3: -For instance, cells that use a lot of energy tend to contain large numbers of mitochondria (the organelle responsible for harvesting energy from food).

Detailed explanation-4: -Skeletal muscles are made of long, thin cells that are packed with highly organized proteins and organelles. During strenuous exercise, the rate of energy use in skeletal muscles can increase by more than 100-fold almost instantly. To meet this energy demand, muscle cells contain mitochondria.

Detailed explanation-5: -The classic role of mitochondria is oxidative phosphorylation, which generates ATP by utilizing the energy released during the oxidation of the food we eat. ATP is used in turn as the primary energy source for most biochemical and physiological processes, such as growth, movement and homeostasis.