As the zombie enters the kitchen where Hieronymous Judson is working, the shot cuts between a view from the doorway and a view from the other side of the room looking back to the door. As it does, the heavy-duty meat cleaver alternates between the blade being horizontal to the cutting board and up at a 45-degree angle. The entire time, Judson's hands are busy with a dead chicken he has already cut.
When the zombie Dr. Boyce bites the fingers of Dr. Langdon, she pulls her mouth away from his hand, stretching the obviously-rubber fingers.
In the kitchen scene with Hieronymous Judson, after the zombie pulls his arm out of the meat grinder, it is obviously a normal-length arm, despite several pounds of ground zombie shown coming out of the grinder.
When Bobby and Judson find the overturned truck in the desert, the camera follows Bobby at such an angle that you can see there is no engine block in the overturned vehicle.