An amoeba can send out pseudopodia to ingest food.

 

What is the mechanism that drives the amoeba to experience "hunger"?

 

In the absence of taste buds or their equivalent, and the absence of gastric juices etc what stimulates the amoeba to "sense" food?

 

Please advise.

 

Thanks in advance.

There are numerous metabolites that act as signal for energy and/or nutrient deficiency. This may include ATP itself or cAMP, for example.

Nutrients are generally sensed via receptors on the cell surface which trigger signaling cascades that in turn control cell motility.