Download Mitochondria - Turning on the Powerhouse

Mitochondria - Turning on the Powerhouse
digestive system
Mitochondria are known as the powerhouses of the cell. They are organelles that act like a
that takes in nutrients, breaks them down,
and creates energy for the cell. The process of creating cell energy is known as cellular respiration. Most of the chemical reactions involved in cellular respiration
happen in the mitochondria. A mitochondrion is shaped perfectly to maximize its efforts.
Mitochondria are very small organelles. You might find cells with several thousand mitochondria. The number depends on what the cell needs to do. If the purpose of
muscle cell
the nerve cell is to transmit nerve impulses, there will be fewer mitochondria in a nerve cell than in a
that needs loads of energy. If the cell feels it
is not getting enough energy to survive, more mitochondria can be created. Sometimes they can even grow, move, and combine with other mitochondria, depending
on the cell's needs.
Mitochondria Structure
Mitochondria have two membranes (not one as in other organelles). The outer membrane covers
the organelle and contains it. The inner membrane folds over many times (cristae). That folding
increases the surface area inside the organelle. Many of the chemical reactions happen on the inner
membrane of the mitochondria. The increased surface area allows the small organelle to do as
much work as possible. If you have more room to work, you can get more work done. Similar
surface area strategies are used by microvilli in your intestinal cells. The fluid inside of the
mitochondria is called the matrix.
Using Oxygen to Release Energy
How are mitochondria used in cellular respiration? The cristae matrix is filled with water (H2O) and
proteins called enzymes. Those enzymes help take glucose food molecules and combine them with
oxygen (O2). The mitochondria are the only place in the cell where oxygen can be combined with the
food molecule and releases energy in a form that our cells can use.
Source: http://www.biology4kids.com/files/cell_mito.html