The intermediate electron acceptor for oxidations that occur in both glycolysis and the Krebs cycle is NAD+ (nicotinamide adenine dinucleotide).

Here's why:

* Glycolysis: In glycolysis, NAD+ is reduced to NADH in the conversion of glyceraldehyde 3-phosphate to 1,3-bisphosphoglycerate. This is a key step where energy is captured from the oxidation of glucose.

* Krebs Cycle: The Krebs cycle also utilizes NAD+ as an electron acceptor. Several steps in the cycle involve the oxidation of substrates, with NAD+ being reduced to NADH. For example, the conversion of isocitrate to alpha-ketoglutarate and the conversion of malate to oxaloacetate both involve NAD+ reduction.

In summary: NAD+ plays a crucial role in both glycolysis and the Krebs cycle by accepting electrons from the oxidation of various substrates, ultimately leading to the generation of ATP through the electron transport chain.