Krebs Cycle

All enzymes of the TCA cycle are located in the mitochondrial matrix except one which is located in inner mitochondrial membranes in eukaryotes and in the cytosol in prokaryotes. This enzyme is:

1.	lactate dehydrogenase	2.	isocitrate dehydrogenase
3.	malate dehydrogenase	4.	succinate dehydrogenase

Which statement is wrong for Krebs' cycle?

1.	There is one point in the cycle where FAD+ is reduced to FADH2 .
2.	During conversion of succinyl CoA to succinic acid, a molecule of GTP is synthesized.
3.	The cycle starts with condensation of acetyl group (acetyl CoA) with pyruvic acid to yield citric acid.
4.	There are three points in the cycle where NAD+ is reduced to NADH + H+.

Identify the step in tricarboxylic acid cycle, which does not involve oxidation of substrate?
1. Succinic acid Malic acid
2. Succinyl-CoA Succinic acid
3. Isocitrate - ketoglutaric acid
4. Malic acid Oxaloacetic acid