It would not be plants, even though it has cell walls. They are not made of chitin. Plants are also not heterotrophic.
Fungi, however, decompose other matter, and have cell walls made of chitin. This would fit the description.
The sense organs that are located on the head and in the mouth of a fetal pig are the Ears, mouth, eyes, nose, and tongue. The pig, just like humans, experiences sound, sight, taste, smell, heat, cold, pain and also balance. The way it responds to these assists humans in the recognition of health and diseases. For instance pain and the posture will often indicate a specific disease such as a fracture of the vertebrae in the spine.
Rotational movements need the most thoracic mobility. This is because a rotational movement (such as twisting) because the movements are more three dimensional, and this is where the most can go wrong. For example, if you were holding a 35lb child and simply bent forward to put him/her down, this is less likely to cause injury than if you were to twist your torso to the right and put the child down. There is a lot more spinal stability and mobility needed for the second motion than the first.