Scientific consensus supports the idea that living organisms require oxygen. Then, a scientist discovers a type of bacteria that metabolizes sulfur instead of oxygen, and thus survives in environments without oxygen. The scientist concludes that a diverse group of many different organisms could live in an oxygen-free environment. Why are some scientists skeptical of the scientist’s results and conclusion?

Coquina, a type of limestone, forms from shell fragments that settle on the ocean floor. what type of rock is coquina?

Which of the following is the most likely outcome of global warming

The kidney filters potentially toxic substances in the blood, and thus “clears” the blood of those substances. this clearance function is dependent upon and proportional to the diffusion gradient of the substance across filtering capillaries, i.e. if the concentration of the substance is doubled, twice as much will be cleared from each ml of blood that is filtered. suppose that the body produces a constant amount of a substance x per unit of time. the kidneys eliminate substance x at a rate directly proportional to the concentration of the substance and the volume of blood cleared each minute (c): elimination = c × [x], where [x] is the steady-state concentration of substance x. imagine an individual with an initial concentration of x equal to [x]0 who develops kidney disease. her baseline clearance c0 drops to one half of the original (½c0). what is the new steady state concentration of x? (for simplicity, assume that substance x is 100% filtered by the kidney).