Answer:
Gastrulation takes place after cleavage and the formation of the blastula and the primitive streak. It is followed by organogenesis, when individual organs develop within the newly-formed germ layers. Each layer gives rise to specific tissues and organs in the developing embryo.Cells in each germ layer differentiate into tissues and embryonic organs. The ectoderm gives rise to the nervous system and the epidermis, among other tissues. The mesoderm gives rise to the muscle cells and connective tissue in the body. The endoderm gives rise to the gut and many internal organs.
Question/Purpose
research
Hypothesis
Experiment
collect data and analyze
Conclusion
I think it would be to exchange gases. When you think about it, plants in the past were always underwater. They didn't have any air. Now, they are on land and need to be able to exchange gases from the leaves to the roots.
The answer u r looking for is- A, all of the above. Hope I’ve helped ;)
