Alt: it's a molecule of kinesin motor protein 'walking' along a microtubule, dragging a vesicle. The kinesin is pink filamentous and has these sort of floppy molecular 'feet' that seem to be striding forward, although these are actually binding domains. It's stepping on a regularly structured green "bridge" and dragging a ball of something dark green and squelchy looking behind it that's studded with little squiggly orange bits. The size of the ball is many times the size of the kinesin character here.