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Mitochondrial Abnormalities in Tetralogy of Fallot Tetralogy of Fallot (TF) is a genetic disorder in which heart malformations result in abnormal blood circulation, so oxygen does not reach body cells as it should. With insufficient oxygen to accept electrons at the end of miotchondrial electron transfer chains, too many free radicals form. This damages the mitochondria—and the cells. In 2004, Sarah Kuruvilla studied mitochondria in the heart muscle of TF patients. Some of her results are shown in FIGURE 7.13.
Patient (age) | SPO2(%) | Mitochondrial Abnormalities in TF | |||
Number | Shape | Size | Broken | ||
1(5) | 55 | + | + | − | − |
2(3) | 69 | + | + | − | − |
3(22) | 72 | + | + | − | − |
4(2) | 74 | + | + | − | − |
5(3) | 76 | + | + | − | + |
6(2.5) | 78 | + | + | − | + |
7(1) | 79 | + | + | − | − |
8(12) | 80 | + | − | + | − |
9(4) | 80 | + | + | − | − |
10(B) | 83 | + | − | + | − |
11(20) | 85 | + | + | − | − |
12(2.5) | 89 | + | − | + | − |
FIGURE 7.13 Mitochondrial changes in tetralogy of Fallot (TF).
(A) Normal heart muscle. Many mitochondria between the fibers provide muscle cells with ATP for contraction. (B) Heart muscle from a person with TF has swollen, broken mitochondria.
(C) Types of mitochondrial abnormalities in TF patients. SPO2 is oxygen saturation of the blood. A normal value of SPO2 is 96%. Abnormalities are marked +.
2. What percentage of the TF patients had mitochondria that were abnormal in size?
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