Concept explainers
Antibiotic Effects on Mitochondria Tetracyclines are antibiotics that inactivate bacterial ribosomes. Knowing that mitochondria evolved from bacteria, researchers suspected tetracyclines might affect mitochondria by harming their ribosomes. FIGURE 19. 11 shows the effects of an experiment in which mice were given either tetracycline or a control antibiotic that affects cell wall production. After 10 days of treatment, the function of mitochondria in the mice was assessed.
FIGURE 19.11 Effects of tetracycline on mitochondria. Mice received low-dose tetracycline, high-dose tetracycline, or a control antibiotic that targets bacterial cell walls. Mitochondrial function was assessed by looking at oxygen consumption rate and ATP content in homogenized mouse livers. Bar graphs show means with standard error. An * indicates a statistically significant difference between the experimental and the control treatments.
How did the two drugs differ in their effect on oxygen consumption by mitochondria?
To determine: The effects of control antibiotic and tetracycline on the oxygen consumption by mitochondria.
Concept introduction: Mitochondria are the powerhouse of the cell. It requires oxygen to produce the ATP in sufficient quantities to perform the energy-requiring reactions in eukaryotic organisms. Tetracycline is an antibiotic that works only against bacterial infections and does not work against viral infections.
Explanation of Solution
Control antibiotic, high dose and low dose of tetracycline are injected to the mice in order to check their oxygen consumption by the mitochondria. The graph shows that the control antibiotic results in higher oxygen consumption rate when compared to tetracycline. The mice that are injected with high and low dose of the tetracycline shows less oxygen consumption by the mitochondria than the control one.
Tetracycline antibiotics have an effect on the oxygen consumption rate in the mice.
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