Answer:
Chitinous exoskeleton and segmented bodies.
Explanation: 
Phylum Arthropoda are known as jointed legs species which include crabs, spiders, ants, etc. The important characteristic of Arthropoda is they have a hard chitinous exoskeleton that provides them protection and gives flexibility. These phylum species can survive in both terrestrial and marine habitats. Some characteristics of phylum Arthropoda are given below:
1) They have Chitinous exoskeleton which is hardened.
2) Their digestive tract is present at opposite ends of the body and complete with the mouth and anus. 
3) They contain jointed limbs.
4) The body structure of these species is showing bilateral symmetry. 
 
        
             
        
        
        
Carbon is relatively small. non - bulky atom that shares electrons easily .
Hope this helps!!!
        
             
        
        
        
Answer:
This is the digestive system.
Explanation:
We can tell that this is the digestive system because we can see #1: The stomach, #2: The small intestine, #3: The large intestine, and #4: The liver. Hope this helped!