With online 3d, actual 3d animation is possible.
The animation you see here is a representation of the developmental stages 9 to 23 of the human heart. You can see the folding of the endocardial tubes right after they fused and form the ventricles and atriums of the heart. The growth in size is proportional.

You can view a 3d animation from all sides, zoom in and out and start and stop it at any time you want. This enables you to get a better understanding of complex subjects.