Practice problem
Choose the correct progression of events.
Gastrula -> Morula -> Zygote -> Blastula
Blastula -> Zygote -> Morula -> Gastrula
Zygote -> Morula -> Blastula -> Gastrula
Gastrula -> Blastula -> Morula -> Zygote
Type a concept, like “slope” or “photosynthesis”.