Nice flowing motion

- these little objects... they are supposed to be blood cells? I don't know a thing about blood cells but I had imagined them to be somewhat more complex structures. And maybe more of them... but you probably did your research and know what they're supposed to look like.

It's hard to get a feel for the walls because they're all grey and one texture.

Nice heart beating in the walls of the vein - hadn't noticed at first

Really interesting start but some more details to the objects to show what they are and give a sort of feel for being fleshy or liquid or organic etc.