During gastrulation in frogs, a rod of mesoderm under the dorsal surface forms the

Notochord

During gastrulation in frogs, a rod of mesoderm under the dorsal surface develops into the notochord which is the precursor of the backbone. The notochord plays an important structural role by serving as the axial skeleton of the embryo until other elements such as the vertebrae forms.

the answer is false?

answer: accepted answer: aquatic animals use the oxygen dissolved in water to carry out respiration. since the amount of dissolved oxygen in water is low as compared to the amount of oxygen in the air, therefore the rate of breathing in aquatic animals is much faster than it is in terrestrial animals.

explanation: