Answer: D) Centrioles
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Centrioles are only found in animal cells and they help during cell division. They organize the spindle fibers that help elongate the cell and separate the chromosomes.
The pH of the stomach in the digestive system is known to be very low, and acidic, so it can break the bonds between molecules, to which the nutrients diffuse into your blood, energizing you.
Muscular dystrophy is a muscle disease that causes a loss in muscle mass and weakness. Patients with muscular dsytrophy may experience a weakening in their cardiac muscles, causings heart malfunction. Muscular dystrophy can also deteriorate the diaphragm, a muscle that solely aids in respiration, causing a breathing malfunction.