Answer:
Mitochondrial biogenesis and mitophagy are two pathways that regulate mitochondrial content and metabolism preserving homeostasis. The tight regulation between these opposing processes is essential for cellular adaptation in response to cellular metabolic state, stress and other intracellular or environmental signals.
Explanation:
Almost the entire system of an embryo is made of cartilage, whereas that of an adult is mostly made of bones.
If it cannot avoid it, it just find a mechanism to use oxygen and make it less harmful to itself. This is how the process of cellular respiration may have evolved
