Final answer:
Ketosis is a condition marked by elevated blood ketone bodies and decreased blood pH, typically as a result of increased fatty acid oxidation in states of carbohydrate deficiency, such as starvation or uncontrolled diabetes.
Step-by-step explanation:
Ketosis is characterized by several factors, which include increased blood levels of ketone bodies and a reduction in blood pH. In conditions such as starvation, diabetes mellitus, and other states where carbohydrates are not sufficiently available, the body resorts to increased fatty acid oxidation leading to a surge in acetyl-CoA levels. The excess acetyl-CoA is then converted into ketone bodies, such as acetoacetate and beta-hydroxybutyric acid. These ketone bodies accumulate and can lead to a state known as ketoacidosis, resulting in a decrease in blood pH. Ketosis is not accompanied by depleted ketone levels, rather the opposite. It also does not involve fat oxidation to pyruvate or an increase in blood pH.