不均皮层，未层次化皮层：大脑皮层的古旧、原始部分，包括古皮层(ar-cheocortex)和旧皮层(paleocortex)；参见neocortex- protonephron
- protonephros
- protoneuron
- protonitrate
- proto-oncogene
- Protopam
- protopathic
- protopecten
- protophyllin
- Protophyta
- protophyte
- protophytology
- protopine
- protoplasia
- protoplasm
- protoplasmatic
- protoplasmic
- protoplast
- protoporphyria
- protoporphyrin
- protoporphyrinogen oxidase
- protoporphyrinuria
- protoproteose
- protopsis
- protosalt