Did the artist intend for the mother to be looking out or looking in? If she is looking towards us then the baby is in the left arm, but if she is looking away from us, the baby is in the right arm.

Was the picture taken from inside the church or from the outside? Another layer of uncertainty.

Was the photographic slide looked at from the front or from the back? More uncertainty.

The answer is that the baby is in the right arm, because we know the mother had a mole on the right side of her face. The inherent asymmetry in the material is in the end what informs us. Protists often, but not always, have evident asymmetries in body form. These can be used to help interpret electron micrographs, but care does have to be exercised.

When looking at electron micrographs we will see organelles with inherent asymmetries.