A mutant protist is found in which some mitochondria lack an inner mitochondrial membrane. Whcih of the following pathways would be completely disruped in these mitochondria?

a) the citric acid cycle.
b) oxidative phosphorylation.
c) the citric acid cycle and glycolysis.
d) alcoholic fermentation.
e) glycolysis.

http://en.wikipedia.org/wiki/Inner_mitochondrial_membrane

http://en.wikipedia.org/wiki/Oxidative_phosphorylation

To determine which pathway would be completely disrupted in mitochondria lacking an inner mitochondrial membrane, we need to understand the functions of each pathway.

a) The citric acid cycle (also known as the Krebs cycle) takes place in the mitochondria and is responsible for extracting energy-rich molecules from glucose, which is then used in subsequent steps of cellular respiration.

b) Oxidative phosphorylation, also occurring in the mitochondria, is the final step of cellular respiration and involves the electron transport chain and ATP synthesis. It relies on the proton gradient across the inner mitochondrial membrane.

c) Glycolysis occurs in the cytoplasm and is the process of breaking down glucose into pyruvate, generating a small amount of ATP and NADH in the process.

d) Alcoholic fermentation occurs in the absence of oxygen and converts pyruvate into ethanol and CO2, regenerating NAD+ without the need for the mitochondrial electron transport chain.

e) Glycolysis, as mentioned earlier, is the initial step of glucose metabolism. It occurs in the cytoplasm and generates a small amount of ATP.

Given that a mutant protist has mitochondria lacking an inner mitochondrial membrane, it means that the electron transport chain, which takes place in the inner mitochondrial membrane, would be disrupted. Therefore, the answer is:

b) oxidative phosphorylation.